Silver complexes carbohydrate

G. N. Thomopoulos, B. A. Schulte, and S. S. Spicer, The infiuence of embedding media and fixation on the post-embedment ultrastructural demonstration of complex carbohydrates. I. Morphology and periodic acid—thiocarbohydrazide-silver proteinate staining of vicinal diols, Histochem. J., 15 (1983) 763-784. 

Peracetylated glucose, brominated in the 1-position, was reacted with V-methylimi-dazole to yield the corresponding carbohydrate functionalised imidazolium salt [114], Reaction with silver(l) oxide and subsequently with [Cp lrCyj yields the silver(I) and iridium(lll) NHC complexes, respectively (see Figure 6.47). The structural parameters of the Cp lr(NHC) complex are similar to those of analogous Cp lr(NHC) complexes featuring nonfunctionalised carbenes [115,116]. 

Several metal oxides (platinum, gold," nickel, copper, ) and cobalt phtalo-cyanine have been employed as surface bound mediators for carbohydrate detection. In a dc amperometric mode of operation detectors based on these mediators exhibit a significant loss of response with time and/or exposure to analyte. Various potential pulse programs have circumvented this stability problem, but at the expense of sensitivity and complexity of the instrumentation. Silver electrodes coated with electrogenerated silver oxide exhibit electrocatalytic activity with respect to carbohydrate oxidation. This paper describes our efforts to utilize an electrode as a carbohydrate detector in a dc amperometric mode. 

Sihca impregnated with saturated and unsaturated hydrocarbons (squalene, paraffin oil) silicone and plant oils complexing agents (silver ions, boric acid, and borates carbohydrates unsaturated and aromatic compounds) chelating compounds [ethylene diamine tetra-acetic add (EDTA), digitonin] transition metal salt synthetic peptides 18-crown-6 and ammonium sulfate silanized sdica gel impregnated with anionic and cationic surfactants Cross-hnked, polymeric dextran gels (Sephadex)... 

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