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
  • sol-gel  (4)
  • Chemistry  (3)
  • ddc:330
  • relative intensity
  • 1995-1999  (4)
  • 1970-1974  (3)
Collection
Keywords
Publisher
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    Encapsulation of the ferritin protein in sol-gel derived silica glasses (1996)
    Springer
    Journal of sol gel science and technology 7 (1996), S. 109-116 
    Details
    ISSN: 1573-4846
    Keywords: ferritin ; sol-gel ; magnetism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract A significant recent development in sol-gel science has been the encapsulation of biomolecules such as proteins and enzymes in optically transparent silica glasses. This paper reports on the encapsulation of an iron (Fe) storage protein, ferritin, to develop a magnetic silica glass. Native ferritin, which has a nanometer-sized microcrystalline Fe oxide core, was encapsulated in optically transparent silica glasses using the sol-gel process. Fe could be released from ferritin but could not be reconstituted into apoferritin when the protein was trapped in the pores of the glass. Transmission electron microscopy of ferritin-doped aged silica gels indicated that crystallinity of the Fe oxide core was retained upon sol-gel encapsulation. Magnetic measurements on ferritin-doped silica gels indicated the material to be paramagnetic, but not superparamagnetic.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00401890
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Spectroscopic Determination of Cholinesterase Activity and Inhibition in Sol-Gel Media (1997)
    Springer
    Journal of sol gel science and technology 8 (1997), S. 1067-1070 
    Details
    ISSN: 1573-4846
    Keywords: cholinesterase ; sol-gel ; pesticide ; THA ; enzyme activity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Biological activity of cholinesterases can be determined by optically monitoring the enzymatic reaction with indophenyl acetate, (N-4′-acetoxyphenyl)-4-quinone imine. At pH 8.0 cholinesterases hydrolyze this yellow dye to yield a blue reaction product. Cholinesterase inhibitors reduce the rate of this hydrolysis. Thus, by monitoring absorbance of the hydrolysis product at its maximum (630 nm) as a function of time, reaction rates of both cholinesterase activity and cholinesterase inhibition may be quantified spectroscopically. Using this technique, we measured the enzymatic activity of butyrylcholinesterase (BuChE) molecules encapsulated in tetramethyl orthosilicate (TMOS) silicate gel-glass prepared by hydrolysis and condensation. This activity is reduced, in a concentration-dependent manner, by the reversible cholinesterase inhibitors 1,5-bis(4-allyldimethyl-ammoniumphenyl) pentan- 3-one dibromide (BADAPP) and 9-amino-1,2,3,4-tetrahydroacridine (THA; tacrine, Cognex). The gel-glasses are rigid and compact, transparent, and porous enough to allow reagents to diffuse in and out.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018350828807
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Spectroscopic determination of cholinesterase activity and inhibition in sol-gel media (1997)
    Springer
    Journal of sol gel science and technology 8 (1997), S. 1067-1070 
    Details
    ISSN: 1573-4846
    Keywords: cholinesterase ; sol-gel ; pesticide ; THA ; enzyme activity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Biological activity of cholinesterases can be determined by optically monitoring the enzymatic reaction with indophenyl acetate, (N-4′-acetoxyphenyl)-4-quinone imine. At pH 8.0 cholinesterases hydrolyze this yellow dye to yield a blue reaction product. Cholinesterase inhibitors reduce the rate of this hydrolysis. Thus, by monitoring absorbance of the hydrolysis product at its maximum (630 nm) as a function of time, reaction rates of both cholinesterase activity and cholinesterase inhibition may be quantified spectroscopically. Using this technique, we measured the enzymatic activity of butyrylcholinesterase (BuChE) molecules encapsulated in tetramethyl orthosilicate (TMOS) silicate gel-glass prepared by hydrolysis and condensation. This activity is reduced, in a concentration-dependent manner, by the reversible cholinesterase inhibitors 1,5-bis(4-allyldimethyl-ammoniumphenyl) pentan 3-one dibromide (BADAPP) and 9-amino-1,2,3,4-tetrahydroacridine (THA; tacrine, Cognex). The gel-glasses are rigid, and compact, transparent and porous enough to allow reagents to diffuse in and out.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02436985
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Allosteric Regulation of Enzymatic Reactions in a Transparent Inorganic Sol-Gel Material (1999)
    Springer
    Journal of sol gel science and technology 15 (1999), S. 57-62 
    Details
    ISSN: 1573-4846
    Keywords: glutamate dehydrogenase ; allosteric regulators ; sol-gel ; enzyme activity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Glutamate dehydrogenase is encapsulated in a transparent porous silicate matrix by using sol-gel techniques. The inorganic polymer is formed around the enzyme (MW 〉 300,000 D). The enzyme is active in the material, catalyzes the reaction of L-glutamate to 2-oxoglutarate and follows Michaelis-Menten kinetics. The allosteric regulators ADP and GTP inhibit or activate the reaction; at pH 6, GTP acts as a strong activator and ADP acts as an inhibitor. This system involves a complex series of interactions; the co-enzyme NAD+ is required for catalysis, large-scale conformational changes accompany the binding of the substrate and coenzyme to the enzyme, the activators/inhibitors must bind to the enzyme to regulate the reactions, and the substrates and products must diffuse through the matrix to and from the binding site. The influence of the unique matrix on the complex enzymatic system is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008713014152
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Oxydation ausgewählter δ,∊- und ∊,ξ-ungesättigter Alkohole mit Blei(IV)-acetat12.Mitt. in der Reihe « Oxydationen einwertiger Alkohole mit Blei(IV)-acetat », 11.Mitt.: [1]. (1974)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 57 (1974), S. 1116-1131 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The lead tetraacetate (LTA) oxidation of dihydro-γ-jonol (2) gives the new bicyclic ether 4 in high yield. On the other hand, LTA oxidation of the alcohols 8, 14, 20, results in the formation of complex mixtures of oxidation products, from which the spiro compounds 10, 16, 22, the bicyclic ethers 11, 12, 17, 18, 23, and the carbonyl compounds 13, 19 have been isolated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19740570419
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Selektive Reduktion von β-Jonon und Dehydro-β-jonon mit Triphenylzinnhydrid (1973)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 56 (1973), S. 1062-1066 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The application of triphenyltinhydride and of triphenyltindeuteride in specific reduction of β-jonone and dehydro-β-jonone has been investigated and the preparation of pure dihydro-β-jonone,dihydro-β-jonone-d1, dihydro-β-jonone-d2, and dihydro-dehydro-β-jonone described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19730560324
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Oxydation von Allylalkoholen mit Blei(IV)-acetat11. Mitt. in der Reihe « Oxydationen einwertiger Alkohole mit Blei(IV)-acetat ». 10.Mitt. vgl. [1]. Über den Inhalt der vorliegenden Arbeit wurde auszugsweise an der Herbstversammlung der Schweizerischen Chemischen Gesellschaft in Lugano am 19. Oktober 1973 vorgetragen [2]. (1974)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 57 (1974), S. 1098-1116 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Lead tetraacetate (LTA) oxidation of the allylic alcohols 1, 10, 14 and 19 leads to the formation of the epoxides 2, 11, 15 and 20, products of a novel internal addition reaction of the electron deficient alcohol oxygen to the allylic double bond. In some cases (10, 14) the formation of a new type of acetoxylated enolethers (12, 16) is observed. The LTA oxidation of the allylic dienols 21 and 29 gives rise to the formation of the epoxyacetates 25 and 33, products of a similar internal addition reaction. Furthermore, a variety of cyclization products (22, 23, 24, 26, 30, 31, 32 and 34) has been isolated whose formation requires an isomerisation of the allylic trans double bond to a cis one.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19740570418
    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...