ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Analytical Chemistry and Spectroscopy  (1,315)
  • Inorganic Chemistry  (688)
  • 1995-1999
  • 1990-1994  (2,003)
  • 1950-1954
  • 1994  (2,003)
Collection
Keywords
Publisher
Years
  • 1995-1999
  • 1990-1994  (2,003)
  • 1950-1954
Year
  • 101
    Electronic Resource
    Electronic Resource
    Isotopic fractionation in secondary ionization mass spectrometry (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 837-843 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: We have studied isotopic fractionation effects which occur during the analysis of oxygen isotope ratios by secondary ionization mass spectrometry. Variable instrumental isotopic fractionation has been well documented in the past as making reliable ion microprobe analyses of oxygen isotopes elusive. We report here techniques for minimizing these effects by careful optimization of an Isolab 54 ion microprobe and a method of integrating the secondary-ion beam to eliminate a major source of fractionation caused by unequal focusing of isotopes on the source slit of the mass spectrometer. A further improvement has been the installation of new ion detectors for measuring 18O- and 17O- secondary ion beams in which the ions strike a conversion dynode (Conversion dynode system - CDS) to release electrons into a channeltron. The CDS detectors have a uniform, high and stable gain which, coupled with the beam integration techniques referred to above, yield reproducible oxygen isotope ratios on both conducting and insulating mineral standards (≤1.2‰ on 18O/16O during a day and 〈2‰ over periods of days and weeks).
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081009
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 102
    Electronic Resource
    Electronic Resource
    Recent events (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 863-863 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081014
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 103
    Electronic Resource
    Electronic Resource
    Calendar of Events (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. i 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081015
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 104
    Electronic Resource
    Electronic Resource
    Masthead (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994) 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081101
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 105
    Electronic Resource
    Electronic Resource
    Substituent effects in the mass spectrometry of 4-substituted camphors studied under electron and chemical ionization (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 876-880 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The electron ionization mass spectra of fourteen 4-substituted (4-X) camphors have been recorded and analyzed using metastable ion analysis and exact mass measurement. With respect to camphor, alkyl substituents changed the relative importance of different fragmentation pathways, though they did not induce new fragmentations. Substituents X connected to the camphor framework through an atom having a lone pair of electrons were generally lost as HX. Overall the fragmentation behaviour was essentially independent of the inductive substituent constant. Under chemical ionization conditions, only methane of the reagent gases produced extensive fragmentations of these compounds; isobutane, acetone and ammonia were ineffective. The nature of the fragmentations was independent of both the inductive substituent constant of the substituent X and the proton affinity and heat of formation of the corresponding neutral compound HX.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081104
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 106
    Electronic Resource
    Electronic Resource
    Conformation dependence in the chemical ionization mass spectra of 3-pinanones (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 313-316 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The conformation of the rigid isomer pair of cis- and trans-3-pinanones was investigated using methane, isobutane, and ammonia chemical ionization (CI) mass spectrometry as a tool to study the dependence of the mass spectrometric fragmentation patterns. The methane and the isobutane CI mass spectra of the cis and trans isomers were found to be different enough to permit the differentiation of the isomers. Each isomer exhibited distinctive fragmentation paths. The isobutane mass spectra of the cis isomer was dominated by the loss of H2O from the pseudo-molecular ion, whereas the loss of C2H4O was the predominant fragment for the trans isomer. Molecular modeling and quantum-chemical computations were used to calculate the conformers of lowest energy for the two isomers. The theoretical calculations were then used to explain the differences observed in the chemical ionization mass spectra.In addition, high resolution mass spectrometry measurements, deuterium labeling experiments and energy calculations of the hypothetical transition states and ionized species were helpful and were used to propose mechanisms for the CI mass spectral fragmentation.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080406
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 107
    Electronic Resource
    Electronic Resource
    Improving the resolution of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry by exploiting the correlation between ion position and velocity (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 865-868 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: By taking into account the correlation between the positions and velocities of desorbed ions in the source region of a time-of-flight mass spectrometer and by including this relationship in the equations used to determine spacefocusing conditions, it is predicted that matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectral resolution can be improved significantly. Experiments involving MALDI of two proteins, insulin and ubiquitin, demonstrate the validity of this concept. Adduct formation does not limit mass spectral resolution in these two cases.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081102
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 108
    Electronic Resource
    Electronic Resource
    The application of electrospray and neutral-loss mass spectrometry to the identification of the metabolites of S12813 in rat liver slices (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 361-365 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The metabolism of S12813, (3-{2-[4-phenyl piperazin-1-yl] ethyl}-2-oxo-2,3-dihydro oxazolo [4, 5-b] pyridine chlorohydrate), in rat liver slice incubates was examined by high performance liquid chromatography combined with mass spectrometry. Electrospray ionization was used together with tandem mass spectrometric techniques of analysis (MS/MS). Polar phase I and phase II metabolites were identified as C-oxidation products, which were then conjugated to form either sulphate or glucuronide metabolites. On the basis of the identifications made, a metabolic pathway of S12813 in rat liver slices has been proposed.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080504
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 109
    Electronic Resource
    Electronic Resource
    Measurement of isotope effect on photodetachment cross-sections of OH- and OD- by Fourier-transform ion cyclotron resonance mass spectrometryContribution from the 2nd European FTMS Workshop, Antwerp, Belgium, September 1993. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 385-387 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Isotope effect on photodetachment cross-sections of OH- and OD- ions was studied using a Fourier-transform ion cyclotron resonance mass spectrometer. The ions were produced by electron impact from a mixture of H2O and D2O gases, trapped in a cylindrical cell and irradiated by a 337 nm photon beam from a nitrogen pulsed laser. Intensities of both ions were measured simultaneously with and without irradiation. This allowed the determination of the ratio of the photodetachment cross-sections of OH- and OD- ions without knowledge of the photon flux intensity and the geometrical overlap factor of laser beam and ion cloud in the cell. From the present result the difference in the equilibrium internuclear distances between OH- and OH was estimated as r(OH-) r(OH) ≍ -0.0074 Å.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080509
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 110
    Electronic Resource
    Electronic Resource
    Peptide sequencing by partial acid hydrolysis and high resolution plasma desorption mass spectrometry (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 906-912 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A method of deriving peptide sequence information using partial acid hydrolysis in combination with accurate mass measurements and immonium ion analysis provided by high-resolution plasma desorption mass spectrometry has been developed. The technique is very simple in terms of the chemistry and involves a short-time (3-30 min) incubation of the peptide in 1N-6N HCl at 100-110°C with subsequent mass spectrometric analysis. Partial acid hydrolysis is found to produce sequence-specific segments, often ladder-like, although not always a complete set. Two application examples of the method are given: the linear peptide bradykinin and desmopressin, a peptide with an internal S—S bond and a non-amino-acid constituent. The technique has proved to be particularly useful in cases where some a priori information on the peptide structure was already known or where the automated Edman degradation technique might yield erratic results or not work at all.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081109
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 111
    Electronic Resource
    Electronic Resource
    Role of coulomb energy in promoting collisionally activated dissociation of multiply charged peptides formed by electrospray ionization (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 933-938 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Electrospray ionization tandem quadrupole mass spectrometry has been applied to a series of lysine-substituted octaalanines and some naturally occurring peptides containing more than two basic amino acid residues. Unusually high fragmentation efficiency along with site-specific cleavages at the outer side of and remote from basic residues were observed for collisionally activated dissociation spectra of multiply charged peptides (MCP) with basic residues in close proximity. It was suggested that Coulomb energy (CE) rather than Coulomb repulsion (CR) was responsible for promoting fragmentation of the MCP studied. A possible fragmentation mechanism of MCP is proposed, in which the conversion of CE into internal vibrational energy was brought about by intramolecular proton migration in the presence of CR between charged sites.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081205
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 112
    Electronic Resource
    Electronic Resource
    Calendar of events (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. i 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080618
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 113
    Electronic Resource
    Electronic Resource
    Maximum entropy deconvolution of heterogeneity in protein modification: Protein adducts of 4-hydroxy-2-nonenal (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 509-512 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: To explore the chemistry of the reactions of the cytotoxic aldehyde trans-4-hydroxy-2-nonenal (HNE) with proteins, we incubated this aldehyde in vitro with β-lactoglobulin B, a model protein of molecular weight 18 277 Da. Direct characterization of reaction products using electrospray ionization mass spectrometry yielded spectra whose complexity suggested extensive product heterogeneity. Spectra were transformed to a true mass scale using both a conventional transform algorithm and a maximum entropy algorithm. Both transformations demonstrated the formation of aldehyde-protein adducts containing from three to nine aldehyde molecules per molecule of protein. Maximum entropy deconvolution resolved Schiff base adducts and/or dehydration products, differing from the Michael addition adducts by 18 Da. The dominant reaction pathway, however, was Michael addition of the aldehyde to nucleophilic functional groups on the protein. The large number of Michael adducts relative to the one available cysteine requires that other amino acids, such as histidine and lysine, also be modified. The data suggest that methods for analysis of HNE that involve displacement of Schiff base groups from proteins will only recover a small fraction of HNE.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080703
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 114
    Electronic Resource
    Electronic Resource
    The methyleneketene radical anion (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 533-534 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The methyleneketene radical anion is formed from Me3SiCOCH=CH2. Deprotonation of this neutral by NH2- yields Me3SiCOC̄=CH2 which then decomposes by loss of Me3Si· to yield CH2=C=C=O-·. The identity of the product radical anion is determined by its charge-reversal (positive ion) mass spectrum.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080708
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 115
    Electronic Resource
    Electronic Resource
    3-aminopicolinic aid as a matrix for laser desorption mass spectrometry of biopolymers (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 1001-1006 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: 3-Aminopicolinic acid (3-APA) was tested and found to be a useful matrix for matrix-assisted laser desorption/ionization of DNA and protein. Single-stranded DNA segments of 150-mer and double-stranded DNA of 246 base pairs were successfully detected by using 3-APA as an ultraviolet-absorbing matrix in a linear time-of-flight mass spectrometer. In the case of the double-stranded DNA, only parent ions corresponding to single-stranded DNA were observed. The comparison with 3-hydroxypicolinic acid and picolinic acid matrices is discussed.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081219
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 116
    Electronic Resource
    Electronic Resource
    Peptide fingerprints after partial acid hydrolysis: Analysis by matrix-assisted laser desorption/ionization mass spectrometry (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 1007-1010 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A method is described by which a sequence-dependent peptide fingerprint can be rapidly obtained upon partial hydrolysis of peptides with hydrochloric acid and subsequent analysis by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). When synthetic peptides are treated with 3M HCI for 5 min at 110°C, amino acids are released in turn from the C-terminus or, depending on the peptide, from the N-terminus. Sequence information can be deduced by identifying the amino acid whose mass corresponds to the difference in MW between the major hydrolysis products, beginning from the MW of the starting peptide. A similar pattern exclusively from the C-terminus has been obtained using pentafluoropropionic acid as a hydrolyzing agent (Tsugita et al. Eur. J. Biochem. 206, 691 (1992)), but required longer hydrolysis time and more handling prior to analysis. The technique we have developed could be used to obtain a sequence-dependent ‘fingerprint’ for a peptide cheaply and rapidly, starting with picomole amounts of peptide, because the hydrolysate can be directly analyzed by MALDI. This methodology might be especially useful for confirming the identity of peptides during peptide mapping.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081220
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 117
    Electronic Resource
    Electronic Resource
    Chemical ionization mass spectra of linear alcohol polyethoxy carboxylates and polyethylene glycol dicarboxylates (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 1016-1020 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The chemical ionization (CI) mass spectra of propylated linear alcohol polyethoxy carboxylates (LAEC) and polyethylene glycol dicarboxylates (PEGDC) have been determined. Olefin displacement of the alkyl chain from the [M + H]+ ions of propylated LAEC formed the protonated polyethoxy carboxyl propyl ester, which then underwent a characteristic fragmentation by first losing water and then ethylene oxides. The fragmentation pattern for PEGDC [M + H]+ ions was similar to that of LAEC, except that the initial steps were displacement of one terminal propyl formate (HCOOC3H7) followed by a neutral loss of CH2O. Strong peaks due to protonated molecules were observed in both LAEC and PEGDC. Product-ion mass spectra obtained from chemical ionization gas chromatographic/triple-stage quadrupole mass spectrometric studies supported the proposed fragmentation mechanisms.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081222
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 118
    Electronic Resource
    Electronic Resource
    Product Announcement (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 1041-1041 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081227
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 119
    Electronic Resource
    Electronic Resource
    A new mass spectrometric approach to detect modifications in DNA (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 1035-1040 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A new approach is described for the enzymatic digestion of DNA yielding oligonucleotides ranging from dinucleoside monophosphates to octanucleoside heptaphosphates. DNA was digested by means of the benzon nuclease, an unspecific nuclease, and alkaline phosphatase to remove the terminal phosphate. The mixture of oligonucleotides was separated using capillary-zone electrophoresis with a buffer system, yielding a rather strong electro-osmotic flow. The oligomers are separated into groups with nucleotides of the same chain length. The separation capillary was used as the innermost capillary of an electrospray spraying system. Negative molecular ions of the nucleotides were recorded using a home-built interface and ion source for a sector-field mass spectrometer. This approach allows the facile detection of DNA modifications since they lead not only to differences in mass, but also can possess altered electrophoretic mobility. For modifying reactions which exhibit sequence specificity, the information is retained in the oligomers. Thus, reactions of DNA with electrophiles can be evaluated at different levels, since in longer chains, even complex sequence specificity may be apparent. Results from calf thymus DNA digests and preliminary experiments with DNA adducts with styrene oxide are discussed.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081226
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 120
    Electronic Resource
    Electronic Resource
    Calender of Events (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. ii 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080822
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 121
    Electronic Resource
    Electronic Resource
    Detection of 500-nucleotide DNA by laser desorption mass spectrometry (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 727-730 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: We report the first detection of DNA segments as large as 500 nucleotides by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry, using picolinic acid and 3-hydroxypicolinic acid mixtures as desorption matrices. The successful detection of 500-nucleotide DNA indicates that laser mass spectrometry is now emerging as a new biotechnology tool for DNA-related research. It should be possible to utilize fast detection of large DNA segments by laser mass spectrometry for rapid human genome sequencing.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080913
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 122
    Electronic Resource
    Electronic Resource
    Peptide ladder sequencing by mass spectrometry using a novel, volatile degradation reagent (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 737-742 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A conceptually novel approach to protein sequencing involves the generation of ragged-end polypeptide chains followed by mass spectroscopic analysis of the resulting nested set of fragments. We report here on the synthesis and development of a volatile isothiocyanate (trifluoroethylisothiocyanate) that allows the identification of several consecutive residues starting with a few picomoles of peptide. The nested set of peptides is generated simply by adding equal aliquots of starting peptide each cycle and driving both the coupling and cleavage reactions to completion. No additional reagents are required to act as chain terminators and retention of the peptide terminal amine allows for subsequent modification with quaternary ammonium alkyl NHS esters to improve sensitivity. Complex washing procedures are not required each cycle, as reagents and by-products are efficiently removed under vacuum, eliminating extractive loss. Multiple peptide samples can be processed simultaneously, with each degradation cycle completed in 35-40 min. The inherent simplicity of the process should allow for easy automation and permit rapid processing of samples in parallel.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080916
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 123
    Electronic Resource
    Electronic Resource
    Masthead (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994) 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080101
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 124
    Electronic Resource
    Electronic Resource
    Photofragmentation in Fourier-transform ion cyclotron resonance: Use or misuse?Contribution from the 2nd European FTMS Workshop, Antwerp, Belgium, September 1993. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 1-9 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The noise in a sector or quadrupele mass spectrometer is determined by the source, i.e. the number of ions present in the signal, whereas in Fourier-transform ion cyclotron resonance it is detector limited. In addition, the Fourier transform spreads white noise equally over the whole spectrum. Thus the accuracy for broad-band spectra is generally rather low. However, the precision, i.e. the reproducibility of successive spectra, is astonishingly high. This fact has been used with much success, for example in collisionally activated dissociation in Hadamard spectra. It is shown that photofragmentation spectra are also very reproducible and thus allow - at least in principle - a ‘kinetic deconvolution’ of a series of such spectra. In such a case, nonlinear regression has to be applied to the data. Since in most kinetics problems several exponential functions are involved, and since it is well known that these exponential functions are notoriously difficult to approximate with a Marquardt-Levenberg algorithm, the validity of the results may be questionable. Three examples (protonated benzene, cycloheptatriene, deuterated toluene) are chosen to demonstrate some of the difficulties and pitfalls of the procedure.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080102
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 125
    Electronic Resource
    Electronic Resource
    Recognition of quaternary ammonium compounds using mass spectrometry (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 65-70 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Liquid secondary-ion mass spectrometry (LSIMS) experiments were performed on a series of model quaternary ammonium chlorides [MQ+Cl-] in order to develop a strategy, via an understanding of cluster-ion formation, for recognition of quarternary ammonium structures. Model structures contained a single quaternary site and various other structural features (for example, conjugated quaternary systems and carboxylic acid groups), using amine hydrochlorides as controls. Cluster ions were examined with both positive- and negative-ion LSIMS, using a range of matrix modifiers. Precursor scans, or ‘molecular weight confirmation scans’, of MQ+ (the charged molecular ion of quaternary ammonium compounds) and [M+H]+ ions were used to assist in the observation of cluster ions and to unambiguously demonstrate precursor/product relationships. Positive-ion experiments typically showed dimeric clusters of [2MQ+ A]+ (A=anion) and [2MQ-H]+ ions, while negative ion experiments produced [MQ + 2A]- ions. Observation of these cluster ions coupled with the lack of an [M-H]- ion are a distinguishing feature of quaternary amines. Additional cluster ions were targeted for distinguishing between protonated amines and quaternary amonium compounds containing a carboxylic acid group. A strategy for recognizing and distinguishing quaternary ammonium structures using LSIMS is proposed, and some initial experiments with thermospray and electrospray are discussed.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080113
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 126
    Electronic Resource
    Electronic Resource
    Matrix-assisted laser desorption ionization for rapid determination of the sequences of biologically active peptides isolated from support-bound combinatorial peptide libraries (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 77-81 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A termination synthesis approach has been developed to encode each resin bead in support-bound combinatorial peptide libraries with the information needed to establish the sequence of the full-length products also contained on the beads. Matrix-assisted laser desorption ionization mass spectrometry was then used to rapidly read the appropriate sequences. In addition to rapid peptide sequencing, the technique allows direct assessment of the quality of the synthetic library, since deletion peptides, side-reaction products and incomplete-deprotection products are readily observed. An anti-gp120 monoclonal antibody was screened against a hexapeptide library, and eight active peptides were isolated. Six of the eight peptides were shown to possess the exact recognition sequence for the antibody.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080115
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 127
    Electronic Resource
    Electronic Resource
    Determination of substituent effects on the proton affinities of natural nucleosides by the kinetic method (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 89-93 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The kinetics of the unimolecular dissociations of proton-bound dimers produced by fast-atom bombardment from nucleosides and reference amines enables the evaluation of the proton affinities (PA) of ribonucleosides. The PAs of cytosine, guanosine, adenosine, uridine and deoxyuridine have been thus determined. These values and those already available for the corresponding DNA homologues allow the evaluation of the effect of the hydroxyl group in position 2′ of the sugar moiety, which lowers the PAs of RNA nucleosides by 0.6-1 kcal/mol, and of the methyl group in position 5 of the thymine ring which enhances the basicity of deoxythymidine over deoxyuridine by 0.6 kcal/mol.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080117
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 128
    Electronic Resource
    Electronic Resource
    Analysis of fumonisin B1 by negative-ion thermospray mass spectrometryContribution No. 93-393-J from the Kansas Agricultural Experiment Station (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 82-88 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Thermospray mass spectrometry was used to analyze fumonisin B1 (FB1) from two corn samples that were known to contain fumonisins, and from a FB1-spiked meat sample. The mass spectrometer was operated in the negative-ion discharge-on, filament-off, mode with the fragmentor set at 200 V. Selected-ion monitoring (SIM) was used for quantitative analysis. The mobile phase was CH3CN (containing 1% CICH2CN, v/v)+0.1M ammonium acetate, pH 3.65 (65:35, v/v). Quantitative analysis was done by integrating the peak areas traced by ion currents of 5 selected ions in SIM, and by the method of standard additions. Responses to the selected ions were linear within the range of 2-200 ng. Fumonisins were easily identified in the corn and muscle tissue matrices without any apparent matrix interferences and were detectable down to 0.1 μ/mL (2 ng injected).
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080116
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 129
    Electronic Resource
    Electronic Resource
    Analysis of pyridinoline and its derivatives by scanning-array four-sector tandem mass spectrometry (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 99-104 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Structures of the trifunctional crosslink molecules, pyridinoline, deoxypyridinoline and glucosylgalactosyl-pyridinoline, have been characterized by positive-ion liquid secondary-ion mass spectrometry (LSIMS) and collision-induced dissociation with scanning-array four-sector tandem mass spectrometry. It has been found that: (i) the naturally occurring cations (Cat+) are readily desorbed by positive-ion LSIMS utilizing glycerol + thioglycerol (1:1) as liquid matrix and dominate the spectra, facilitating accurate mass measurement; (ii) changing the matrix to 3-nitrobenzyl alcohol leaves little evidence of the cation, and (iii) collision-induced dissociation of the cations (Cat+) of pyridinoline, deoxypyridinoline and glucosylgalatosyl-pyridinoline gives a wealth of fragmentation for structure elucidation. These fundamental studies of tandem mass spectra of the known trifunctional crosslink molecules provided valuable structure-related information, which help in the identification of the tissue-specific peptides containing these crosslinks. Artefact ions in these tandem mass spectra are remarkably abundant.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080119
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 130
    Electronic Resource
    Electronic Resource
    Mass spectrometric investigation on some pyrilium salts by different. Ionization methods and metastable ion studies (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 163-166 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A series of pyrilium hydrochlorides (Py+ClO-4) have been studied by means of both electron ionization and fast-atom bombardment (FAB) methods. Only for some compounds does electron ionization show the formation of Py+, together with [Py - H]+· ions. Metastable ion data indicate that the former also originate through H· loss when their formation could be explained by loss of perchloric acid through a thermal process directly from the salt. Many fragment ions, related to the original structures, are also detected. In contrast, in FAB conditions, all the compounds show the formation of Py+ without any fragmentation products, proving its effectiveness in the easy identification of the related molecular species. Only by the mass-analyzed ion kinetic energy spectra of Py+ ions can a valid characterization of the compounds under study be achieved.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080207
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 131
    Electronic Resource
    Electronic Resource
    Letter to the editor (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 339-340 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080412
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 132
    Electronic Resource
    Electronic Resource
    Award announcement (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 340-340 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080413
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 133
    Electronic Resource
    Electronic Resource
    1994 Directory of mass spectrometry manufacturers and suppliers (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 343-357 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: An annual directory of companies which supply mass spectrometers and mass spectrometry components and services.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080502
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 134
    Electronic Resource
    Electronic Resource
    Reactions of Sc+, Ti+, V+, Fe+, Co+ and Ni+ with 1-fluoronaphthalene in the gas phase. Metal-catalyzed oligomer formation and observation of unusual ring fragmentation (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 366-370 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Poly(naphthalyne) is of interest, in particular, due to its intrinsic electrical conductivity. Reported here are the initial steps in the metal-catalyzed polymerization of naphthalene as observed in the gas-phase reactions of Sc+, Ti+, V+, Fe+, Co+, and Ni+ with 1-fluoronaphthalene studied in a Fourier-transform mass spectrometer. Sc+, Ti+, V+, and Fe+ were found to dehydrofluorinate in a sequential fashion up to three neutral fluoronaphthalene molecules to form ions of the form MC10H+6, MC20H+12 and MC30H+18, where M represents the metal. Sc+ showed unusual reactivity by also being able to eliminate C2H2 from fluoronaphthalene, and Ti+ was found to eliminate a hydrogen atom to form TiC10H6F+. Second- and higher-order reactions were studied and several ionic products from primary and secondary reactions were investigated by collision-induced dissociation. Formation of unmetallated ions was also observed. For example, C20H+12 was determined to arise from MFC20H+12, for M = Ti, V, while for iron it was formed directly from FeC10H+6 in its reaction with the neutral fluoronaphthalene. This is in contrast with the behavior expected from an earlier study of fluorobenzene, where it was observed that (C6H4)+n species arose from M(C6H4)+n species.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080505
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 135
    Electronic Resource
    Electronic Resource
    Masthead (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994) 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080601
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 136
    Electronic Resource
    Electronic Resource
    Mass shifts due to ion/ion interactions in a quadrupole ion-trap mass spectrometer (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 451-454 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Mass spectra recorded using a Paul ion trap, operated in the mass-selective instability scan mode, give peak positions which are shown to depend on ion abundance. The isolated molecular ions of benzene, anisole, cresol, and n-butylbenzene are ejected during the mass selective instability scan at times which display a linear dependence on ion abundance for low populations of trapped ions. Remarkably, the degree to which the peaks are shifted is also compound dependent. Mass shifts are also influenced by the presence of other ions in the trap and this effect is amplified as the mass difference between the analyte and matrix ions decreases. Mass shifts are also affected by the helium pressure which controls the ion density. Extrapolation to zero ion abundance and to zero helium pressure is suggested as a method of eliminating these effects and hence of improving the mass measurement accuracy attainable using the ion trap.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080604
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 137
    Electronic Resource
    Electronic Resource
    Tryptic peptide mapping of sequence 1-298 of human serum albumin by high-performance liquid chromatography and fast-atom bombardment mass spectrometry (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 459-464 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The determination of the tryptic peptide mapping of sequence 1-298 of human serum albumin (HSA) by chemical and enzymatic cleavage and combined use of high-performance liquid chromatography (HPLC) and fast-atom bombardment mass spectrometry (FAB-MS) is described. A total coverage of about 75% of the entire sequence was obtained. Unidentified fragments included some peptides which were not present in the chromatograms because of their extreme hydrophobic or hydrophilic character, as indicated by the calculated retention times. Due to the high reproducibility of the experiments and to the satisfactory yield of the tryptic fragments identified, the combined use of HPLC and FAB-MS appears to possess great potential for structural investigation of HSA.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080606
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 138
    Electronic Resource
    Electronic Resource
    High temperature mass spectrometric study of 3Al2O3 · 2SiO2 (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 478-480 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The high-temperature Knudsen effusion method was used to study the vaporization processes and thermodynamic properties of mullite from 1833 K to 2033 K. Data on the activities of Al2O3 and SiO2 and on the entropy, enthalpy and Gibbs energy of formation of mullite were obtained. It was shown that the atomization energy of the AlSiO gaseous molecule (1062±25 kJ/mol) is close to the values that have been obtained earlier.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080610
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 139
    Electronic Resource
    Electronic Resource
    Mass-selective analysis of ions in time-of-flight mass spectrometry using an ion-trap storage device (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 487-494 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A quadrupole ion trap was used as a front-end device for selecting specific ions formed via matrix-assisted laser desorption for analysis in time-of-flight mass spectrometry. Using low-voltage auxiliary RF signals, the ion trap can be used to resonantly eject all but a selected mass-to-charge range prior to time-of-flight mass analysis. A series of simple analog resonance ejection circuits were developed to provide this selective ion trapping. These circuits use both single- and modulated-frequency waveforms applied directly to the repeller endcap of the quadrupole ion-trap source in a monopolar fashion. Commercially available waveform generators, as well as a multichannel voltage-controlled oseillator circuit, were used for resonant ion ejection and ion isolation prior to pulsed extraction into the time-of-flight mass spectrometer. The analytical utility of these circuits was tested on a series of biologically active peptides from m/z 700 to 1650 using matrix-assisted laser desorption/ionization (MALDI) directly into the ion trap. These simple analog circuits were found to provide a number of useful qualitative improvements in the ion-trap/reflectron time-of-flight device including the broadband removal of matrix background ions formed via MAI DI and the isolation of molecular ions from complex peptide mixtures. The utility of this methodology for tandem mass spectrometry, including collision-induced dissociation and photodissociation, is discussed.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080613
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 140
    Electronic Resource
    Electronic Resource
    Interpretation of mass spectra, 4th edition F. W. McLAFFERTY AND F. TUREČEK Published by University Science Books, Mill Valley, 1993 ISBN 0-935702-25-3, xiii + 371 pp. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 501-501 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080616
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 141
    Electronic Resource
    Electronic Resource
    Masthead (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994) 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080701
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 142
    Electronic Resource
    Electronic Resource
    Laser desorption/gas-phase ionization of the amino acid tryptophan (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 731-734 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A solution of tryptophan, rhodamine B and glycerol is irradiated in the source region of a time-of-flight mass spectrometer by visible light from a pulsed laser. Tryptophan and rhodamine B are desorbed and subsequently ionized by a second pulse of ultraviolet light. The observed mass spectra and dependence of ion yields on time delay between light pulses provide information about the laser desorption process.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080914
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 143
    Electronic Resource
    Electronic Resource
    Probing conformational changes in some proteins by positive-ion electrospray mass spectrometry (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 144-148 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Charge-state distributions in the positive-ion electrospray (ES+) mass spectra of some proteins are monitored at various temperatures of the ion source. The observed shifts in charge-state profiles favouring higher charge-states are linked to heat-induced conformations cited by other research groups. To gain more insight into the origin of the observed shifts, a number of measurements were also performed at different flow rates of the electrospray drying gas, on both aqueous and organic solutions of protein. The flow rate of the drying gas was found to influence the relative intensities of high charge-states induced by heat or organic solvents to a small extent, but it did not produce substantial shifts in the charge-state distributions observed in room temperatures ES+ mass spectra of aqueous solutions.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080203
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 144
    Electronic Resource
    Electronic Resource
    Multinuclear ions of ferrocene [Fen(C5H5)n+1]+ (n = 2, 3 and 4) in the gas phase identified by mass spectrometry (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 155-157 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Under methane chemical ionization conditions, multinuclear ions of ferrocene [Fen(C5H5)n+1]+ (n = 2, 3 and 4), resulting from the ion/molecule reactions in the gas phase, were detected by mass spectrometry. Structures for these ions are elucidated, according to their mass-analyzed ion kinetic energy spectra, to be triple-, quadrupole-, and quintuple-decker sandwiches, respectively, and the formation pathways for them are also discussed.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080205
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 145
    Electronic Resource
    Electronic Resource
    Collision-induced dissociations of three C3H3O- isomers. An interesting hydride-transfer reaction (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 167-168 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The major collision-induced fragmentation of CH2=C=C(H)(O-) occurs following hydride transfer to form CH2=CH—-C=O which then loses carbon monoxide to form deprotonated ethene (C2H-3).
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080208
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 146
    Electronic Resource
    Electronic Resource
    The application of capillary electrophoresis/mass spectrometry using negative-ion electrospray ionization to areas of importance in the textile industry (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 179-182 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The feasibility of using capillary electrophoresis/mass Spectrometry, with negative-ion electrospray ionization, for applications of relevance to the dyeing and textile industries has been shown. Structurally similar examples of solubilized vat dyes of different halogen content have been separated and identified with a view to investigating the photodegradation processes which occur when the dyes are subjected to UV light. Separations of the various species formed when a mordant dye is chrome treated are also presented, indicating the ability to study complex formation arising from the different chrome dyeing methods.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080211
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 147
    Electronic Resource
    Electronic Resource
    Selective injection of laser desorbed ions into a quadrupole ion trap with a filtered noise field (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 174-178 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: We demonstrate the advantages of utilizing a broad-band filtered noise field (FNF) for preferential mass injection of laser desorbed ions into an ion-trap mass spectrometer (ITMS). The FNF waveform is applied to the endcap electrodes of the ITMS during the laser-desorption period, and its amplitude and frequency spectrum are adjusted to resonantly eject all ions except those with selected mass-to-charge ratios. In single-pulse laser desorption, the FNF rapidly ejects desorbed matrix ions without reducing the number of target ions that are trapped. When the FNF is used in conjunction with multipole laser-desorption events, accumulation of target m/z ions results in a 40-fold increase in sensitivity over single-shot laser desorption. In addition, the application of sequential filtered noise fields for multiple stages of mass spectral interrogation is demonstrated.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080210
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 148
    Electronic Resource
    Electronic Resource
    A method to increase contaminant tolerance in protein matrix-assisted laser desorption/ionization by the fabrication of thin protein-doped polycrystalline films (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 199-204 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: This paper describes the fabrication and use of thin polycrystalline films in matrix-assisted laser desorption experiments. These films consist of microcrystals of protein-doped matrix (crystal dimensions ≤ 1 μm). The films produce intense protein-ion currents and can be grown in the presence of high concentrations of involatile solvents (e.g., glycerol, 6 M urea) without any purification. They strongly adhere to the substrate, allowing easier washing of the film, compared to dried-droplet deposits. The films are also more uniform than dried-droplet deposits, with respect to ion production. It is suggested that matrix-assisted laser desorption/ionization samples are composed of nonlinear optical devices that function as polymer ion-current sources. These devices (protein-doped matrix crystals) can be designed and fabricated in many forms to serve the special functions required by the analytical scientist.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080215
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 149
    Electronic Resource
    Electronic Resource
    Obituary (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 222-223 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080219
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 150
    Electronic Resource
    Electronic Resource
    Practical Organic Mass Spectrometry: A Guide for Chemical and Biochemical Analysis (2nd Edn) J. R. CHAPMAN Published by John Wiley & Sons, Chichester, England, 1993 ISBN 0-471-9253-8 Price £39.95; 330 pp. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 225-225 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080221
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 151
    Electronic Resource
    Electronic Resource
    Charge-remote fragmentation of sulphated and glucuronidated bile acids and their 2-aminoethanesulphonic acid derivativesPaper delivered in part at the 11th Informal Meeting on Mass Spectrometry, Budapest, 1993. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 227-236 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Negative-ion fast-atom bombardment mass spectra of bile acids show prominent [M - H]- pseudomolecular ions, and few fragment ions. Collision-induced dissociation of such pseudomolecular ions gives charge-remote fragmentations which are useful in structural identifications. It has been shown that bile acids conjugated with taurine (2-aminoethanesulphonic acid) give more intense and informative collision-induced dissociation spectra than unconjugated bile acids. In this laboratory, a procedure for the aminosulphation of biological samples, for analysis by tandem mass spectrometry, has been developed. In the present study, a comparison has been made between the collision-induced dissociation spectra of a series of sulphated and glucuronidated bile acids and their 2-aminoethanesulphonic acid derivatives.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080302
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 152
    Electronic Resource
    Electronic Resource
    Matrix-assisted laser desorption/ionization with an external ion source Fourier-transform mass spectrometer (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 237-241 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Mass spectra of several model oligopeptides (substance P, [Arg8]-vasopressin, tyrothricin, and the B-chain of bovine insulin) have been obtained with a matrix-assisted laser desorption/ionization (MALDI) source and a custom-designed Fourier-transform mass spectrometer (FTMS). The MALDI source is outside the magnetic field in a separately pumped external chamber, and ions are injected through the fringing fields of the magnet and into the FTMS analyzer cell by a long quadrupole mass filter that is operated in the RF-only mode. A large window on the ion source housing makes it easy to point and focus the laser beam onto the sample probe tip. A good quality mass spectum is achieved for 0.5 pmol of substance P, and the mass resolution for the B-chain of bovine insulin is 19000.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080303
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 153
    Electronic Resource
    Electronic Resource
    Gas-phase rearrangements involving homoenolate anions. The isocamphanone/camphor rearrangement (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 262-264 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Deprotonated isocamphanones rearrange to deprotonated camphor in the gas phase, presumably via the intermediacy of a homoenolate anion.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080308
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 154
    Electronic Resource
    Electronic Resource
    The use of low-energy collisionally activated dissociation negative-ion tandem mass spectrometry for the characterization of dog and human urinary metabolites of the drug BW 1370U87 (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 265-273 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Liquid chromatography (LC) combined with atmospheric pressure chemical ionization mass spectrometry was used to identify phase I and II metabolites of the drug BW 1370U87 in dog and human urine. Additional analysis of individual high-performance liquid chromatograph fractions collected from dog urine by combined gas chromatography/mass spectrometry identified one metabolite which was not detected by LC/MS methods. Using negative-ion LC/MS, the majority of BW 1370U87 metabolites in human urine were identified as glucuronic acid conjugates of phase I oxidative metabolites. The negative-ion fragmentation produced by low-energy collisionally activated decomposition (CAD), studied by tandem mass spectrometry experiments, confirmed that these compounds were drug-related and allowed metabolite structures to be assigned. Product-ion spectra of the metabolites were dominated by the loss of neutral molecules from even-electron deprotonated [M - H]- ions.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080309
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 155
    Electronic Resource
    Electronic Resource
    Obituary (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 289-289 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080313
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 156
    Electronic Resource
    Electronic Resource
    Cluster ions EDITED BY C.-Y. NG. T. BAER AND I. POWIS Published by John Wiley & Sons, Chichester, 1983, ISBN 0471938300 Price £80.00 (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 291-291 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080315
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 157
    Electronic Resource
    Electronic Resource
    Electron ionization and fast-atom bombardment mass spectrometry of some new macrocycles containing triethanolamine derivatives and 1,3,5-triazine moieties (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 293-298 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The behaviour of four open-chain analogues of crown ethers (polypodands) have been studied under both electron ionization and fast-atom bombardment conditions with the aid of mass-analyzed ion kinetic energy spectroscopy and accurate mass measurements. In electron ionization, extensive fragmentations, closely related to the original structures, are observed, while fast-atom bombardment, leading to the formation of abundant protonated molecules, allows easy establishment of the molecular weight. The presence of odd-electron cations in distonic form and the occurrence of cyclization reactions are discussed.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080402
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 158
    Electronic Resource
    Electronic Resource
    Formation of deprotonated molecules [M - H]- of α-tocopherol under fast-atom bombardment conditions (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 309-312 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The formation of deprotonated molecules, [M - H]-, of α-tocopherol under fast-atom bombardment (FAB) conditions has been discussed on the basis of a proton subtraction reaction between analyte and matrix molecules. The use of proton-accepting matrices such as diethanolamine (DEA) and pentamethyleneglycol (PMG) gave higher intensities of the [M - H]- ion and more definitive spectral data than when other matrices, a 1:2 (v/v) mixture of thioglycerol (TG) and dithiothreitol (DTT), or m-nitrobenzylalcohol (m-NBA), were used. The order of proton acceptability evaluated for the matrices used was DEA〉PMG〉DTT〉m-NBA. It was concluded that the proton acceptability, which is measured by gas-phase basicity or proton affinity, is a most important factor for the formation of both [M + H]+ and [M - H]- ions under FAB conditions. Further, the formation of molecular ions, M+·, under FAB conditions and the formation of [M - H]- ions by electron impact have been discussed by using α-tocopherol.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080405
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 159
    Electronic Resource
    Electronic Resource
    C60-assisted laser desorption/ionization mass spectrometry in the analysis of phosphotungstic acid (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 881-885 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: An application of C60-assisted laser desorption/ionization mass spectrometry to a heteropoly inorganic system: phosphotungstic acid, H3PO4(WO3)12, is presented. A nitrogen laser (337 nm) on a linear tandem time-of-flight mass spectrometer is used for the observation of the laser-power dependence of mass spectra of this material.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081105
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 160
    Electronic Resource
    Electronic Resource
    Ion/molecule reactions in the gas phase: Comparison of the enantioselectivity of two chiral gasesPresented at the 13th IMSC, Budapest, 1994. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 891-894 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Stereochemistry study has always been a very important subject, but the determination of chirality has become potentially possible with the emergence of chemical ionization. In this study, mass spectrometry and tandem mass spectrometry (MS/MS) were used as a tool for distinguishing the isomers of (+) and (-) isopinocampheols and (+) and (-) menthols by ion/molecule reaction in the gas phase using two different chiral gases, G. The reactive plasma is made up of the ion GH+. Interactions between the plasma and the isomer M of (+) and (-) isopinocampheols and (+) and (-) menthols lead to the formation of the ions [M-M2O+H]+, [M-H2O+GH]+, [M+GH]+ and [2M+H]+. In mass spectrometric analysis, their relative intensities differ because of the absolute configuration of M. In MS/MS the relative intensities of the daughter ions of [M-H2O+GH]+ ions enable a positive determination of (+) and (-) isomers. The susbtitution ion [M-H2O+GH]+ arises via an SN2 pathway that is regioselective and sterospecific.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081107
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 161
    Electronic Resource
    Electronic Resource
    Gas-phase reactions of transition metal carbonyl anions and atomic metal anions with nitrous oxide and dioxygen: Oxygen atom transfer and ligand exchange in reactions with nitrous oxide (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 895-905 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The gas-phase reactions of a series of metal carbonyl anions M(CO)n- (M=Cr, n=2-5; M=Mn, n=1-5; M=Fe, n=1-4) with nitrous oxide and dioxygen have been studied by use of Fourier-transform ion cyclotron resonance (FTICR) mass spectrometry. With nitrous oxide, most of the metal carbonyl ions react by oxygen atom transfer leading to oxo-metal anions and oxo-metal carbonyl anions. The Cr- and Fe- ions also react relatively easily with nitrous oxide by oxygen atom abstraction to form CrO- and FeO-, respectively. Experiments with N15NO reveal that loss of a CO molecule from a collision complex is a significant ligand exchange channel for the Mn(CO)3-, Mn(CO)4- and Fe(CO)4- ions. The nitrous oxide molecule remains intact in the resultant product ions, M(CO)n(N2O)- with M=Mn, n=2 and 3; and M=Fe, n=2. The losses of 15NN and 15NN + CO in the collision-induced dissociations of the Mn(CO)3(N15NO)- ions, in combination with the relatively facile occurrence of oxygen atom transfer, are taken to mean that coordination of the metal centre to the oxygen atom is preferred over bond formation to the terminal nitrogen atom of the nitrous oxide molecule. The metal carbonyl anions react readily with dioxygen to form mainly oxo-metal ions as well as oxo- and dioxo-metal carbonyl anions in relative yields which depend on the nature of the metal and the number of CO ligands in the reactant ion.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081108
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 162
    Electronic Resource
    Electronic Resource
    Award Announcements (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 922-922 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081113
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 163
    Electronic Resource
    Electronic Resource
    Recent events (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 920-921 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081112
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 164
    Electronic Resource
    Electronic Resource
    Monomer mapping: A PC-based software tool facilitating the determination of monomer compositions from mass spectrometric molecular weight data (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 917-919 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A method has been developed to establish the monomer composition of (bio)macromolecules. The method, which we call monomer mapping, involves mass spectrometry and a computer program. Given the (nominal) m/z value of the molecular ion as well as the elemental compositions of all monomeric residues possibly present, the computer program generates all fitting monomer compositions and their corresponding m/z ratios. The determination of the monomer composition is enabled by verification of the presence of a signal at the calculated m/z ratios for the individual monomers, using high resolving power mass spectrometry. Monomer mapping can be used to determine monomer compositions of individual components in mixtures without applying (chromatographic) separation techniques. The scope of monomer mapping has been enlarged by combining it with the results of per-O-methylation, which gives information on the number of exchangeable hydrogens. The results of, for instance, amino acid analysis could also be included in the program. Monomer mapping has been successfully applied to determine the glycosyl compositions of saponins.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081111
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 165
    Electronic Resource
    Electronic Resource
    Editorial (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 923-924 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081202
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 166
    Electronic Resource
    Electronic Resource
    Ion fragmentation activated by matrix-assisted laser desorption/ionization in an ion-trap/reflectron time-of-flight device (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 407-416 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: An ion-trap storage/reflectron time-of-flight mass spectrometer has been used to study the decay of large ions following activation by matrix-assisted laser desorption/ionization (MALDI). It is shown that large ions may undergo fragmentation over long periods of time, extending even to milliseconds in some cases. These fragments are stored in the trap and detected as stable ions in the reflectron device, rather than as metastable ions due to decay during the flight time to the detector. The ion decay is found to depend strongly on the laser intensity, while a smaller effect may be due to the matrix used in the MALDI process. The fragmentation observed was found to also depend strongly on the RF voltage applied to the ring electrode; higher RF voltage produced enhanced fragmentation. A gated RF experiment further demonstrated the importance of the level of the RF voltage, during the initial activation event, in producing fragmentation. A study of the effects of buffer gas composition and pressure showed that increased pressure may result in reduced fragmentation due to collisional cooling in the trap. However, the use of argon or nitrogen buffer gas at increased pressure in the trap may result in fragmentation upon extraction from the trap, producing metastable ions in the flight tube. The implications of the use of the time variable for obtaining fragmentation in the trap for rapid sequencing are discussed.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080514
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 167
    Electronic Resource
    Electronic Resource
    Masthead (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994) 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081201
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 168
    Electronic Resource
    Electronic Resource
    Positive-ion fast-atom bombardment tandem mass spectrometry of peptide nucleic acids (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 925-928 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The base sequence of synthetic peptide nucleic acids (PNAs), novel antisense agents, was analyzed by positive-ion fast-atom bombardment tandem mass spectrometry (FAB-MS/MS). Upon high-energy collisional activation decomposition, PNA oligomers provided apparent MS/MS product ions resulting from specific cleavage along the PNA backbone.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081203
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 169
    Electronic Resource
    Electronic Resource
    Exact fields in multi-electrode ion optics (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 939-941 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The exact determination of electrostatic potential is vital in specifying the resolution in ion-beam focusing devices such as quadrupole mass spectrometers (QMS). Current numerical routines are marked by poor convergence on boundaries and become unwieldy when the number of electrodes, 2n, is greater than four, or when the structure is modified. Using a conformal transformation we have succeeded in finding the exact electrostatic potential distribution everywhere within a QMS which contains four cylindrical electrodes. All the coefficients in the multipole expansion of the potential are readily calculated. The boundary value problem is solved by matching coefficients on the electrode surface, which is a circle embedded in the transformed coordinate frame. We have proven that for every allowed position of the electrode centre, R, there exists a corresponding electrode radius, r, for which the dodecapole term in the potential expansion vanishes. Our analytically obtained relationship between the above-mentioned parameters differs slightly from that in current use. As these parameters are based on an exact solution, their practical use in mass determination may be considerable.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081206
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 170
    Electronic Resource
    Electronic Resource
    Screening and characterization of atrazine metabolites by liquid chromatography/tandem mass spectrometryPresented at the 11th Annual Meeting of the French Mass Spectrometry Society, held at Rouen, 20-22 September 1994. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 945-952 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The ability of liquid chromatography combined with positive-ion low-collision-energy tandem mass spectrometry for screening and characterization of atrazine metabolites in aqueous solutions is examined. The strategy used was defined after investigations on the structure and origin of the main daughter ions through experiments done by desorption chemical ionization with NH3 or ND3 as reagent gas. Following this, a three-step procedure was proposed which included parent-ion spectra based on [XC=N—C(=NH)NH2]+ (with X = Cl or OH) ions apparently formed via ion-dipole complexes and found to be highly diagnostic for chlorotriazines and hydroxytriazines respectively.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081208
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 171
    Electronic Resource
    Electronic Resource
    Influence of cooling time on the internal energy of ions subjected to resonance excitation in a quadrupole ion trapPresented at the 11th Annual Meeting of the French Mass Spectrometry Society, held at Rouen, 20-22 September 1994. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 953-956 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: This study demonstrates the influence of cooling time, applied prior to (and after) resonance excitation, on the internal energy carried by ions subjected to tickle excitation. Competitive fragmentations of ionized butylbenzene have been used to estimate the internal energy average transferred during collision processes. Two competitive effects have been observed by using a delay time before tickle: kinetic energy relaxation (up to 15 ms) related to an internal energy decrease effect and, at higher cooling time values, collisional excitation with helium buffer gas allows one to increase the internal energy of precursor ions.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081209
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 172
    Electronic Resource
    Electronic Resource
    Sequential product-ion spectra (MS3) with array detection and reaction-intermediate scanning of a cyclopeptide on a five-sector mass spectrometerPresented at the 11th Annual Meeting of the French Mass Spectrometry Society, held at Rouen, 20-22 September 1994. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 960-966 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A new strategy, based on sequential product-ion spectra (MS2 and MS3) and reaction-intermediate scanning (MS3), provides a rapid and unambiguous sequence determination of E-destruxin, a cyclodepsipeptidic toxin from Metarrhizium anisopliae fungus.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081211
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 173
    Electronic Resource
    Electronic Resource
    Self-calibrating property of matrix-assisted laser desorption/ionization time-of-flight spectra of polymeric materials (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 981-984 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A calibration procedure is introduced, which allows one to obtain absolute mass values in matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) spectra of polymeric materials, thus avoiding ambiguous mass assignments. The method consists in combining the observed times of flight in a function denoted as ‘modified sum of squares’ (SS2) and in finding the point of minimum for SS2. The procedure takes advantage of the finding that SS2 possesses an extremum property, i.e. it takes its minimum at θ, the mass of the first oligomer appearing in the MALDI-TOF spectrum. The method was tested by recording the MALDI-TOF spectrum of an aminolyzed Nylon 6 and of a glycolized poly(butyleneadipate) (PBA) sample. Nylon 6 was found to be made of a series of oligomers bearing diaminohexamethylene (DAHM) terminal groups. PBA is made of a series of oligomers with butyleneglycol end-groups. The intense peaks seen in the mass spectra are due to sodium-cationized ions, whereas the less-intense peaks are due to potassium-cationized ions. The function SS2 was built for the two samples and a point of minimum was found at the point θ = 817.6 for Nylon 6 and at the point θ = 713.6 for PBA. This finding allowed the interpretation of the mass spectra.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081215
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 174
    Electronic Resource
    Electronic Resource
    Mass spectrometric investigations of fullerenes. I. Vapour pressure over the C60/C70 binary system (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 985-990 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The absolute vapour pressures over pure C60, C70, fullerite and over the binary C60/C70 system are calculated from ion intensities vs. temperature up to 800 K using the Knudsen effusion mass spectrometric method. The vapour pressures (Pa) of C60 and C70 are given as a function of temperature (K) by the equations: \documentclass{article}\pagestyle{empty}\begin{document}$$ \begin{array}{l} \log p = - (8276.4 \pm 120)/T + 10.49 \pm 0.14,{\rm for }C_{60} \\ \log p = - (9106.4 \pm 130)/T + 10.70 \pm 0.15,{\rm for C}_{{\rm 70}} \\ \end{array} $$\end{document} Corresponding Second Law enthalpy and entropy changes for sublimation are: \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l} \Delta H_{{\rm subl}}^0 = 158 \pm 3{\rm kJ}/{\rm mol }\Delta {\rm S}_{{\rm subl}}^{\rm 0} = 105 \pm 1.5{\rm kJ}/{\rm mol}, for C_{60} \\ \Delta H_{{\rm subl}}^0 = 174 \pm 3{\rm kJ}/{\rm mol }\Delta {\rm S}_{{\rm subl}}^{\rm 0} = 109 \pm 1.5{\rm kJ}/{\rm mol, for C}_{{\rm 70}} \\ \end{array} $$\end{document} Results are discussed in terms of sample purity and pretreatment and correlated with data obtained by other authors. Fullerenes containing residual organic solvents (fullerite) partly decompose upon thermal treatment to amorphous carbon.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290081216
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 175
    Electronic Resource
    Electronic Resource
    Masthead (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994) 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080801
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 176
    Electronic Resource
    Electronic Resource
    Microsecond pulsed glow discharge time-of-flight mass spectrometer (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 590-594 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A linear time-of-flight mass spectrometer (TOFMS) has been designed, constructed, and coupled with a glow discharge source in microsecond pulsed mode (MSPGD). Orthogonal acceleration, a DC quadrupole and deflecting pulse techniques are used to diminish kinetic distribution and the spatial distribution of ions, and for deflecting Ar+ ions in their flight path. Comparison was made in the same discharge source between MSPGD and DC discharge. The continuous ion current is only 0.2 nA in the DC discharge mode, while the peak ion current reaches over 100 nA in the MSPGD mode. In addition, the ratio of the repelled ions to total ions is much higher in MSPGD than with a DC discharge in TOFMS. The mechanism of MSPGD is discussed. A resolving power of 500 was achieved, which is excellent for elemental analysis. To the authors' knowledge, this is the first time that a MSPGD-TOFMS combination has been described. The system is now being further optimized to improve its performance.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080804
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 177
    Electronic Resource
    Electronic Resource
    Determination of fumonisins using on-line liquid chromatography coupled to electrospray mass spectrometry (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 603-606 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Fumonisin (FB) mycotoxins are produced by Fusarium monoliforme, which grows primarily on yellow corn. Ingestion of FB1-contaminated food causes leukoencephalomalacia in horses, pulmonary edema in pigs, and is suspected in the etiology of human esophageal cancer. Chromatographic separation and detection of underivatized fumonisins has been hampered because these compounds are nonvolatile, thermally labile, and devoid of chromophoric functional groups. We report here a simple liquid chromatography/mass spectrometry method employing chromatographic separation on a polymer-based column coupled with sensitive detection using positive-ion electrospray mass spectrometry for the quantification of fumonisins B1, B2 and B3 in extracts of commercial corn meal.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080807
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 178
    Electronic Resource
    Electronic Resource
    Mass determination of human immunoglobulin IgM using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 627-631 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Monoclonal human immunoglobulin IgM has been analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Using a matrix of sinapinic acid with a laser wavelength of 355 nm, positive ions with 2 to 6 charges were observed in the mass spectra. Two major molecular species were present. The molecular weights estimated from the multiply-charged signals were found to decrease systematically with decrease in the charge state of the ion. This effect was determined to stem from the non-linear influence of the initial kinetic energy of desorption on the final kinetic energy of the multiply-charged species. A method of successive approximations, with the molecular weights and desorption velocities of the analytes as variables, was used to correct for these non-linearities. Mean molecular weights for the two IgM species were found to be 939 000 ± 2000 and 982 000 ± 2000 Da. An initial desorption velocity of 565 ± 10 ms/s was determined for both.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080811
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 179
    Electronic Resource
    Electronic Resource
    On-line buffer removal and fraction selection in gradient capillary high-performance liquid chromatography prior to electrospray mass spectrometry of peptides and proteins (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 621-626 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The technique for on-line removal of buffers and for fraction selection to eliminate source clogging and suppression of electrospray ionization by unwanted constituents consisted of: (i) selecting the initial mobile phase composition to retain analytes on top of a capillary high-performance liquid chromatography (HPLC) column; (ii) washing the buffer isocratically to waste, using a two-way micro dump valve; (iii) starting the gradient and switching the dump valve to introduce analytes into the source. Peptide and protein mixtures were prepared in 0.05-0.5 M phosphate and 0.55 mM tris-based buffers, and water. After buffer removal, chromatograms and electrospray spectra were indistinguishable from those of aqueous controls, down to 1 pmol (acidic fibroblast growth factor) consumed, and up to 78 kDa (bovine transferrin) molecular weight. Aided by the dump valve, 100 fmol of angiotensin could be fractionated and identified on the slope of a 10 × 106 fmol of leucine enkephalin HPLC peak. On-line buffer removal and fraction selection eliminate the need for additional preparation steps than can lead to excessive sample losses.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080810
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 180
    Electronic Resource
    Electronic Resource
    Mass spectrometry at Padua (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 637-638 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080813
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 181
    Electronic Resource
    Electronic Resource
    Mass spectrometry in stereoisomer characterization: The case of 1,3,4-trideoxy-3-fluoronojirimycins and 1,3,4-trideoxy-3-fluoromannojirimycins (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 653-658 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The mass spectrometric characterization of stereoisomeric 1,3,4-trideoxy-3-fluoronojirimycins and 1,3,4-trideoxy-3-fluoromannojirimycins has been achieved by means of metastable ion studies. In particular, mass-analyzed ion kinetic energy spectroscopy performed on the electron-ionization-generated molecular species of the title compounds has led to an easy and unequivocal differentiation of the four stereoisomers under study, by their unusual diagnostic fragmentation mechanisms.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080816
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 182
    Electronic Resource
    Electronic Resource
    Excitation and detection geometries for Fourier-transform mass spectometryContribution from the 2nd European FTMS Workshop, Antwerp, Belgium, September 1993. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 10-13 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A short overview of current excitation and detection techniques for Fourier-transform mass spectrometry and related ion cyclotron resonance experiments is given, and some ideas are discussed which may lead to new developments.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080103
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 183
    Electronic Resource
    Electronic Resource
    Internal ion impact ionization for Fourier-transform ion cyclotron resonanceContribution from the 2nd European FTMS Workshop, Antwerp, Belgium, September 1993. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 14-21 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A general scheme for ionization and fragmentation of ions in Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICRMS) is introduced. The technique is based upon excitation of high-frequency (i.e. lowmass) primary ions (e.g. N+·2, Al+, H2O+·) which may be generated by standard ionization methods (e.g. electron ionization or laser desorption) inside the trap. Generation of the primary ions is followed by excitation of their cyclotron motion to high translational energy to serve as projectile ions. The projectiles serve two functions: to ionize neutral gas atoms and/or molecules (secondary ions) within the trap internal ion impact ionization (IIII), and to collisionally activate the secondary ions to induce fragmentation. Ionization by IIII is analogous to charge-exchange ionization, in which a primary ion reacts with neutral analyte to produce ionization. When the projectile ions' cyclotron orbits are not excited (even for very long delay periods between ionization and detection), lower ion abundances are observed for the secondary ions derived from the neutral analyte(s), verifying that high energy ion impact must be responsible for the relatively high ion abundances observed when projectile cyclotron motion is excited: i.e., the mechanism of IIII is likely to be high-energy charge exchange. Several advantages of the new technique include: accessibility of very high impact energy (keV) in FT-ICRMS in both the laboratory and the center-of-mass frames of reference; ease in controlling the average energy transferred from projectiles to sample neutrals by moderation of the projectile ion's cyclotron radius; and the high ion-molecule reaction rates attainable in FT-ICR due to the long path length for trapped primary projectile ions at low pressure. Theory of ion formation and the problems associated with this technique (e.g. formation of secondary ions at different pre-excitation ICR orbits) are discussed.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080104
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 184
    Electronic Resource
    Electronic Resource
    Mass measurement accuracy of matrix-assisted laser desorbed biomolecules: A Fourier-transform ion cyclotron resonance mass spectrometry studyContribution from the 2nd European FTMS Workshop, Antwerp, Belgium, September 1993. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 26-31 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The use of binary matrices and internal calibrants to improve the mass measurement accuracy in matrix-assisted laser desorption ionization (MALDI) with Fourier-transform ion cyclotron resonance (FTICR) mass spectro-metry is described. Binary matrices enhance the analyte ion yield and enable a complete MALDI-FTICR mass spectrum to be obtained from a single laser shot. The advantage of single-laser-shot data acquisition is that it eliminates line-broadening due to shot-to-shot frequency variations. It is shown that unresolved product ions, mainly due to loss of H2O and/or NH3, shift the centroid of an unresolved multi-component peak. A mass measurement accuracy of 12 ppm was obtained for the bovine insulin [M+H]+ ion using melittin as an internal calibrant.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080106
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 185
    Electronic Resource
    Electronic Resource
    Desorption - ionization of organic compounds studied by Fourier-transform laser microprobe mass spectometryContribution from the 2nd European FTMS Workshop. Antwerp, Belgium, September 1993. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 40-45 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The recently developed FT LMMS with an external ion source has been applied to selected organic molecules. Some aspects of the ion formation processes from solids under focused laser irradiation at 266 nm were investigated. Specifically, the effect of laser energy and the time profile of ion production were studied. First, the generation of intact cations, fragments and thermal decomposition products from a quaternary ammonium salt were evaluated at distinct times after the laser pulse. The mass spectra of phenol red in its neutral and salt form were recorded under different conditions with respect to laser irradiation power density conditions and ion formation after the laser pulse. The results allow the refinement of previous concepts about ionization in LMMS.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080108
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 186
    Electronic Resource
    Electronic Resource
    A regiospecific cycloaddition: Successive reactions of ·CH2CH2OH+2 with CH2OContribution from the 2nd European FTMS Workshop, Antwerp, Belgium, September 1993. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 53-55 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Four dominant reactions can be observed when the β-distonic ion ·CH2CH2OH+2 reacts in the cell of a Fourier-transform ion cyclotron resonance spectrometer with a number of neutral molecules: protonation of the neutral molecule, ethylene radical-cation transfer, hydride abstraction from the neutral molecule, and charge exchange. Among the ethylene transfer reactions, which can lead to a variety of other distonic ions, we have throroughly studied the reaction with formaldehyde. The reaction of a first molecule of CH2O yields ·CH2CH2OCH+2. The addition of a second one leads to 1,3-dioxane which stabilizes by H· loss. This latter reaction is regiospecific.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080110
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 187
    Electronic Resource
    Electronic Resource
    Mass spectrometric studies on azasqualenes, a class of 2,3-oxidosqualene cyclase inhibitors (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 59-64 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The mass spectrometric behaviour of a series of azasqualenes and azasqualanes has been studied by two different instruments, a double focusing machine and an ion-trap mass spectrometer (ITMS). The high abundances of fragmentation products obtained using the former indicate that with ITMS, processes additional to electron ionization must be present, leading to molecular species with lower internal energy contents.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080112
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 188
    Electronic Resource
    Electronic Resource
    Capillary column supercritical fluid chromatography/mass spectrometry of polycyclic aromatic compounds using atmospheric pressure chemical ionizationNRCC # 34889. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 105-110 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Capillary column supercritical fluid chromatography (SCF) was combined with atmospheric pressure chemical ionization (APCI) mass spectrometry through a heated pneumatic-nebulizer interface, originally developed for liquid chromatography/mass spectrometry (LC/MS), and subsequently modified for use with supercritical fluid chromatography/mass spectrometry (SFC/MS). A high pressure syringe pump was used to pass SFC-grade carbon dioxide, used as the mobile phase, through a capillary SFC column which was contained in an oven, maintained at 100°C. The eluent passed through the heated pneumatic-nebulizer interface into the ionization region of the mass spectrometer with the aid of the flow of nebulizing gas. The system was optimized using benz[a]anthracene, and then applied to analyze a standard mixture of polycyclic aromatic compounds (PACs) as well as complex mixtures of PACs obtained by the fractionation of a pond sediment contaminated by coke-oven residues. A detection limit of 40 pg was established for chrysene.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080120
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 189
    Electronic Resource
    Electronic Resource
    The evaluation of several electrospray systems and their use in non-covalent bonding studies (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 120-125 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A number of different designs of electrospray sources have been used to study the non-covalent interaction between ribonuclease A and cytidylic acids. Signal differences were observed between the various types of source giving rise to very different spectra. However, in all cases, information was obtained relating to the putative complex.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080122
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 190
    Electronic Resource
    Electronic Resource
    Electron impact mass spectrometry of some 5-amino salicylic acid derivatives (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 158-162 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The electron impact-induced fragmentation processes of eleven differently substituted 5-amino salicylic acids were studied by means of mass-analyzed ion kinetic energy (MIKE) spectroscopy, parent-ion spectroscopy and accurate mass measurements. Most of the fragmentation processes are related to the cleavages of the 5-amino substituents. Unusual behaviour is that related to the CO2 loss from the molecular ion, quite significant in the normal electron ionization spectra and completely undetectable in the MIKE spectra.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080206
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 191
    Electronic Resource
    Electronic Resource
    Matrix-assisted laser desorption/ionization of restriction enzyme-digested DNA (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 183-186 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Matrix-assisted laser desorption/ionization, by a time-of-flight mass spectrometer, has been successfully used for detection of restriction enzyme-digested DNA. However, the oligonucleotide segments detected correspond to the molecular weights of single strands.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080212
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 192
    Electronic Resource
    Electronic Resource
    Cathodic bombardment and sputtering in the 0.5-4.0 torr pressure region of a glow-discharge ion sourcePresented in part at the 12th International Mass Spectrometry Conference, Amsterdam, The Netherlands, 1991 (Book of Abstracts, p. 250), and also appears in part in: D. M. P. Milton, Ph.D. Thesis, University College of Swansea, 1991. (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 187-194 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Cathodic ion sputtering energies have been studied in a glow-discharge ion source, operated in the ranges 0.5-2.0 Torr pressure and 100-1000 V discharge voltage using ion kinetic energy spectroscopy. Average energies in the range 10-20 eV were measured. These energies are very low compared with the theoretical prediction of the charge-transfer model. In view of this, the high sputtering yields measured are surprising. It is inferred that the sputtering is caused, not by the discharge gas ions as is still widely believed, but by fast discharge-gas atoms. A means of estimating the average energy of the neutral flux is found by comparing presently measured thresholds with Literature values directly obtained. The average energy seems to be about three times greater than that of the ions. The neutral flux is crudely estimated by comparison of the apparent nett sputter yields measured here with tabulated primary values and taking into account back-diffusion. It is found to be 〉 100 times larger than the ion flux. The flux created by charge transfer alone is therefore not enough to explain the high sputtering yields measured. Higher energy ions detected and composed mainly of ionized cathodic atoms appear to be formed in a region intermediate between the negative glow and the cathode, which again is different from the generally held view.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080213
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 193
    Electronic Resource
    Electronic Resource
    Optimization of skimmer voltages of an electrospray ion source coupled with a magnetic sector instrument (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 205-210 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: An electrospray ion source designed for a magnetic sector instrument usually has two skimmers, which are located behind a capillary exit with separate pumping stages to reduce the pressure from that of ambient air to a valve suitable for the sector instrument. This work describes an evaluation of these two skimmer voltages with respect to the charge-state distributions and the focusing efficiency of ions. The skimmer voltages were found to be closely related to the m/z values of the detected ions. The optimal difference voltage between skimmers 1 and 2 increased in proportion to the m/z values of the ions, irrespective of the molecular masses of the associated substances. This phenomenon is ascribable to the ion-focusing effect in this region rather than to the effects of energetic collisions in the region of the skimmers, and suggests that the skimmer voltages should be adjusted in accordance with the m/z values of the detected ions for efficient acquisition of all distributed ions. The work demonstrates the functional role of the skimmers in electrospray ionization mass spectrometry with a magnetic sector instrument by examining several types of peptides and proteins, as well as an analysis of a complex mixture of peptides.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080216
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 194
    Electronic Resource
    Electronic Resource
    Masthead (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994) 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080301
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 195
    Electronic Resource
    Electronic Resource
    Influence of laser focusing in matrix-assisted laser desorption/ionization (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 242-247 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: The influence of laser focusing on the target in matrix-assisted laser desorption/ionization (MALDI) has been studied. The emission of stable and metastable molecular ions of bovine insulin depends on both the laser energy and the distance between the target and the laser focal plane. The results clearly show that the laser fluence is the important parameter in MALDI. The fluence threshold of metastable-ion emission is higher than that of stable-ion emission. Beyond this threshold, the emission of stable ions reaches a plateau. This is due to the spatial inhomogeneity of the laser energy distribution. A phenomenological model including two fluence thresholds for the stable- and metastable-ion emission has been developed and compared to the experimental data.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080304
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 196
    Electronic Resource
    Electronic Resource
    Calender of events (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. ii 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080222
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 197
    Electronic Resource
    Electronic Resource
    Halocarbenes as diagnostic tools for mass spectral localization of double bonds (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 248-251 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Different halocyclopropanes prepared by cycloaddition of halocarbenes to olefins by phase-transfer reactions have been analyzed by gas chromatography/mass spectrometry (GC/MS). Starting from CCl2-adducts, the investigations have been extended to bromine- and fluorine-containing cyclopropanes. As reaction partners, a group of olefins, containing different alkyl substituents, have been selected. Thereby, special attention has been paid to smooth reaction conditions, high reaction yield and simple handling. The suitability for mass spectral analysis is discussed. Fragmentation pathways and diagnostic potential are evaluated. Best results have been obtained by addition of bromofluorocarbene to double bonds. The resulting bromofluorocyclopropanes are considered to be the most promising derivatives for mass spectral localization of double bonds.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080305
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 198
    Electronic Resource
    Electronic Resource
    Letter to the Editor (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 287-288 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080312
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 199
    Electronic Resource
    Electronic Resource
    Application of thermally assisted electrospray ionization mass spectrometry for detection of noncovalent complexes of bovine serum albumin with growth hormone releasing factor and other biologically active peptides (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. 280-286 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Ion-spray ionization mass spectrometry with gentle conditions for solvent removal has been reported as a useful tool for detection of high-affinity noncovalent complexes of biological relevance formed in solution. Two main objectives of this study were (i) to find whether other types of electrospray ionization (ESI) sources, e.g. where the solvent is removed with the help of heat (thermally assisted electrospray), could be utilized for detection of noncovalent biological complexes of high and low affinity and (ii) to find whether ESI-MS can be used for detection of the association of bovine serum albumin (BSA) with biologically active peptides. Using a well-defined high-affinity association of FK506 with its binding protein (FKBP) as model system we proved that ESI-MS with thermally assisted interphase can be used for detection of the FK506-FKBP complexes in a similar way as was previously shown for electrospray mass spectrometry (Ganem et al., J. Am. Chem. Soc. 113, 6294 (1991)). In mixtures of BSA with a 9-10 molar excess of biologically active peptides, such as growth hormone releasing factor (GRF), glucagon, bradykinin or insulin in ammonium acetate at pH 7.5, complexes with a ratio of 1:1, 1:2 and in some cases 1:3 were detected. On the other hand, these complexes disappeared upon acidification, pointing to their noncovalent nature. To our knowledge, this is the first evidence that relatively weak and nonselective association of proteins (represented here by BSA) with peptide ligands have been detected by ESI-MS in addition to well documented examples of highly specific molecular recognition phenomena like, for example, those reported for receptor-ligand, enzyme-substrate, or enzyme-inhibitor systems. Our results also show that electrospray ion sources of different design are amenable for performing studies of binding.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080311
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 200
    Electronic Resource
    Electronic Resource
    Calendar of Events (1994)
    New York, NY : Wiley-Blackwell
    Rapid Communications in Mass Spectrometry 8 (1994), S. ii 
    Details
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/rcm.1290080316
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...