![Sample our Physical Sciences journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/110819/TOC-Subject-Sample-2021-Physical-Sciences.jpg"})
Abstract
A highly sensitive, stable and interference free glucose biosensor was developed based on covalent immobilization of glucose oxidase on a platinized platinum wire and further covering with a nonconductive heteropolypyrrole film. The film was formed by electropolymerization of pyrrole and a substituted pyrrole, 4-(3-pyrrolyl)-4-oxobutyric acid. After covering with the heteropoly-pyrrole film, the electrode showed responses to ascorbate, urate and 4-acetamidophenol less than 1.0%, 1.0% and 2.0% of those of the electrode without covering, respectively. Furthermore, the stability of the modified electrode was improved from one month to three months and the linear response range of the modified electrode increased from 0.1–10 mM to 0.1–30 mM compared with those of the electrode without the film, respectively. The determination limit of both the bare and modified electrodes was 0.05 mM and their response time of 90% steady value was both in the range of 5–15 s. Due to platinization, the surface area of the electrode was largely improved and much more enzyme was immobilized; both the bare glucose oxidase electrode and the heteropolypyrrole film covered electrode showed high sensitivities of 750 nA/mM and 300 nA/mM, respectively.