Amperometric response of polypyrrole entrapped bienzyme films

We have constructed a bienzyme electrode for the detection of total cholesterol by incorporating cholesterol esterase and cholesterol oxidase in polypyrrole films. The in situ deposition of both enzymes during the electrochemical polymerisation of pyrrole provides a simple procedure for the immobilisation of biomolecules at electrodes. Our study shows that cholesterol oxidase entrapped in polypyrrole films grown at platinum electrodes gave a fast amperometric response to cholesterol and good storage stability. The sensitivity of polypyrrole-entrapped cholesterol esterase/cholesterol oxidase electrodes to cholesteryl oleate was established. © 1992.