Poly amine sites

Another approach is to occlude into the electroconductive polymer film a second polymer that contains functionalities to which indicator molecules may be conveniently covalently attached. Guiseppi-Elie and Wilson [180] coelectropolymerized pyrrole and 3-(l-pyrrolyl)-propionic acid in the presence of poly(styrenesuIfonic acid) and polyvinylamine (PVAm). Incorporation of the PV Am into the polymer film confers free primary amines on the surface of the film. Using aqueous cross-linking chemistry Guiseppi-Elie and Wilson conjugated the suc-cinamide ester of NHS-LC-biotin to the primary amine sites of the polymer surface. A simple variation on this theme can produce a wide variety of chemical and biological sensors. The occlusion of human serum albumin (HSA) [154] or bovine serum albumin (BSA) by electropolymerization in electroconductive polymer can also provide —COOH, —NH2, and —SH sites for the convenient attachment of indicator molecules. Likewise, macromolecular counteranions may be functionalized prior to or following occlusion into the CEP membrane. 

The Zincke reaction has also been adapted for the solid phase. Dupas et al. prepared NADH-model precursors 58, immobilized on silica, by reaction of bound amino functions 57 with Zincke salt 8 (Scheme 8.4.19) for subsequent reduction to the 1,4-dihydropyridines with sodium dithionite. Earlier, Ise and co-workers utilized the Zincke reaction to prepare catalytic polyelectrolytes, starting from poly(4-vinylpyridine). Formation of Zincke salts at pyridine positions within the polymer was achieved by reaction with 2,4-dinitrochlorobenzene, and these sites were then functionalized with various amines. The resulting polymers showed catalytic activity in ester hydrolysis. ... 

Deacylation rates of acetylsalicylate by isopropylated polymer at pH 7.3 were markedly slower than with unmodified polymer (Table III). With 2.4xlO-2 total residue molar concentration of isopropylated and unmodified poly(ethylenimine), respectively, k2, the pseudo-first-order rate for the former was 1.45 x 10-3 min-1, for the latter 1.2 x 10-1 min-1. Clearly, primary amines are the major sites for aminolysis of aspirin. 

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