Glucose biosensor based on immobilization of glucose oxidase on a carbon paste electrode modified with microsphere‐attached l‐glycine

In the present study, a novel biosensor that is sensitive to glucose was prepared using the microspheres modified with (4‐formyl‐3‐methoxyphenoxymethyl)polystyrene (FMPS) with l‐glycine. Polymeric microspheres having Schiff bases were prepared from FMPS using the glycine condensation method. Glucose oxidase enzyme was immobilized onto modified carbon paste electrode by cross‐linking with glutaraldehyde. Oxidation of enzymatically produced H2O2 (+0.5 V vs. Ag/AgCl) was used for determination of glucose. Optimal temperature and pH were found as 50 °C and 8.0, respectively. The glucose biosensor showed a linear working range from 5.0 × 10−4 to 1.0 × 10−2 M, R2 = 0.999. Storage and operational stability of the biosensor were also investigated. The biosensor gave perfect reproducible results after 20 measurements with 3.3% relative standard deviation. It also had good storage stability.