Simple method for preparing glucose biosensor based on in-situ polypyrrole cross-linked chitosan/glucose oxidase/gold bionanocomposite film

A film of chitosan–polypyrrole–gold nanoparticles was fabricated by in-situ chemical synthesis method and its application in glucose biosensor was investigated. The obtained biosensor exhibited a high and reproducible sensitivity of 0.58 μA/mM, response time ~ 4 s, linear dynamic range from 1 to 20 mM, correlation coefficient of R2 = 0.9981, and limit of detection (LOD), based on S/N ratio (S/N = 3) of 0.068 mM. A value of 1.83 mM for the apparent Michaelis–Menten constant was obtained. The resulting bio-nanocomposite provided a suitable environment for the enzyme to retain its bioactivity at considerably extreme conditions, and the decorated gold nanoparticles in the bio-nanocomposite offer good affinity to enzyme.