Poly indole-5-carboxylic acid

A conducting, polymeric film of poly(indole-5-carboxylic acid) has been employed for covalent immobilization of tyrosinase, which retains catalytic activity and catalyzes oxidation of catechol to the quinone <2006MI41>. Poly(l-vinylpyrrole), polyfl-vinylindole), and some methyl-substituted compounds of poly(l-vinylindole) are of potential interest as photorefractive materials with a relatively low glass-transition temperature and requiring a lower quantity of plasticizer in the final photorefractive blend <2001MI253>. Polymers of 5,6-dihydroxyindoles fall within the peculiar class of pigments known as eumelanins and their chemistry has been reviewed <2005AHC(89)1>. 

However, in the latter case, the electrode substrate was a platinum or a gold disc, so that oxygen reduction may occur at the electrode/PPy interface [36] Poly-(3-methylthiophene) [37] and poly(indole-5 carboxylic acid) [38] have also shown inherent electrocatalytic activity towards the oxidation of NADH and ascorbate, without the use of electron transfer mediators. These results have been interpreted by a higher efficiency of charge transfer from an organic-based electrode to an organic substrate. 

SELF-DOPED POLY(INDOLE-5-CARBOXYLIC ACID)... 

Figure 5.41 Cyclic voltammograms of a poly(indole-5-carboxylic acid)-coated platinum electrode at different pH. The data for pH 1.2, 3.0 and 5.0 were recorded in a Mcllvaine buffer containing 0.1 M NaCl. In all cases, the sweep rate was lOmV/s. (A) 2.5 M HCl, (B) pH 1.2, (C) pH 3.0, (D) pH 5. Journal of the Chemical Society, Faraday Transactions, 1992, 88, 2685, P. N. Bartlett, D. H. Dawson, J. Farrington. Reproduced by permission of The Royal Society of Chemistry.)...

Ligure 5.42 Redox reaction in poly(indole-5-carboxylic acid) (P5C02H). (Reproduced from Journal of Applied Polymer Science, 2005, 98, 917. Reprinted with permission of John Wiley Sons, Inc.)... 

Poly(o-aminophenol) (PAP) Poly(aniline)-poly(vinylsulfonate) Poly(indole-5-carboxylic acid) Poly(phenosafranine)... 

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