Novel amperometric glucose biosensor based on covalent immobilization of glucose oxidase on poly(pyrrole propylic acid)/Au nanocomposite

A glucose biosensor is fabricated with immobilization of glucose oxidase (GOx) on poly(pyrrole propylic acid)/Au nanocomposite by covalent attachment. Poly(pyrrole propylic acid) (PPyAA)/Au nanocomposite was prepared by chemical oxidation of pyrrole propylic acid monomer by using chloroauric acid (HAuCl4) as an oxidizing agent. The obtained nanocomposites were used to fabricate highly sensitive amperometric glucose biosensor which exhibited a high and reproducible sensitivity of 0.42 μA/mM, response time ∼2 s, linear dynamic range from 1 to 18 mM, correlation coefficient of R2 = 0.9981, and limit of detection (LOD), based on S/N ratio (S/N = 3) of 0.05 mM. A value of 1.83 mM for the apparent Michaelis–Menten constant K m app was obtained. The high sensitivity, wider linear range, good reproducibility and stability make this biosensor a promising candidate for portable amperometric glucose biosensor.