Nanoelectrode ensembles based on conductive polyaniline/poly(acrylic acid) using porous sol–gel films as template

Abstract

Porous sol–gel (PSG) film has been utilized as a template for the electrochemical polymerization of aniline in presence of poly(acrylic acid) (PAA). The presence of electroactive polyaniline (PAn)/PAA within the porous skeleton of the sol–gel films has been confirmed using cyclic voltammetry, UV–vis spectrometry and atomic force microscopic measurements. The densities and the sizes of the nanoelectrodes can be controlled easily using electrochemical methods. The conductive polymer “wires” of PAn/PAA formation in PSG matrix can behave as an ensemble of closely-spaced but isolated nanoelectrodes. Moreover, the nanoelectrode ensembles based on conductive PAn/PAA for glucose biosensing are fabricated by immobilization of glucose oxidase (GOx) and Nafion onto the surface of conductive polymer. Owing to the biocompatibility of PSG and electro-activity of PAn/PAA at neutral pH regions, the glucose biosensor shows excellent characteristics and performance, such as low detection limit and fast response time.