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
  • 1
    Electronic Resource
    Electronic Resource
    Ultrahigh-resolution matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectra of peptides (1995)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 30 (1995), S. 825-833 
    Details
    ISSN: 1076-5174
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Quasimolecular peptide [M + H]+ ions are generated by matrix-assisted (2,5-dihydroxybenzoic acid/D-fructose) laser desorption/ionization (frequency-tripled Nd: YAG at 355 nm) from leucine enkephalin, bradykinin, the non-apeptide Arg-Leu-Cys-Ile-Phe-Ser-Cys-Phe-Arg, angiotensin I, bovine insulin chain B and some of their deuterated derivatives. The ions are cooled and axialized by azimuthal quadrupolar irradiation in the presence of argon collision gas in the ‘source’ compartment of a dual cubic Penning trap. Following ion transfer to the low-pressure ‘analyzer’ trap, ultrahigh FT-ICR mass resolving power is obtained for protonated oligopeptide quasimolecular [M + H]+ ions: e.g. m/Δm50% ≈ 1 500 000 for bradykinin (m/z ≈ 1060) after frequency drift correction and 100 000 for insulin B-chain, in which Δm50% is the magnitude-mode peak full width at half-maximum peak height. These results constitute the highest mass resolving power yet demonstrated for internally-generated MALDI ions at 3 T, and compare favorably with results obtained at much higher-magnetic field with externally-generated ions. High mass resolution is important for resolving adducts and chemical modifications of a peptide or protein and (as demonstrated here) for facile determination of the degree of deuteration from an H/D exchange experiment. Limitations to FT-ICR mass resolving power by Coulombic ion-ion interactions at high ion density in the trap are demonstrated experimentally and discussed.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jms.1190300607
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Long-range electronic interactions in androstanediones (1997)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 63 (1997), S. 797-803 
    Details
    ISSN: 0020-7608
    Keywords: long-range electronic effects ; MNDO SCF calculations ; 13C-NMR ; androstanediones ; Chemistry ; Theoretical, Physical and Computational Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The results of MNDO SCF MO calculations on 5α-androstane (1), androstan-3-one (2), androstan-16-one (3), androstan-17-one (4), androstane-3,16-dione (5), and androstane-3,17-dione (6) and the experimental 13C-NMR chemical shifts observed in various solvents (C6D12, CDCl3, CD3CO2D, CD2Cl2, CD3COCD3, CD3OD, CD3CN) were used to assess the nature of long-range interactions between 3,16- and 3,17-carbonyl groups in androstanediones. The 13C-NMR results appear to confirm the proposition that the interactions in androstane-3,16-dione are stronger. © 1997 John Wiley & Sons, Inc. Int J Quant Chem 63: 797-803, 1997
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...