Electrochemical preparation of self-doped poly(N-(3-sulfonicpropion) anilide) and its application in sensing ethanol

A novel containing sulfonic acid group aniline monomer, N-(3-sulfonicpropion) anilide, was synthesized in three steps and subsequently to be electropolymerized on a glassy carbon electrode (GCE). The resulting self-doped poly(N-(3-sulfonicpropion) anilide) (SPAN/GCE) held 79.5% electrochemical activity when transferred from 0.1 M pH 7.0 PBS to 0.1 M pH 10.0 PBS, indicating its remarkable extension of the redox activity. The SPAN/GCE was characterized by X-ray photoelectron spectroscopy (XPS) and found that 30% of the nitrogen atoms are sulfonated. Preliminary experimental results show that after the immobilization of alcohol dehydrogenase (ADH) on the SPAN/GCE (ADH/SPAN/GCE), the ADH/SPAN/GCE showed good electrocatalytic activity toward the oxidation of ethanol. These reveal that the SPAN/GCE is quite promising in the fields of biosensors, biofuel cells and other bioelectrochemical devices.