Preparation of amperometric biosensor for cholesterol determination

ABSTRACTIn this study, a new amperometric biosensor for determination of cholesterol oxidase was developed. For this purpose platinum/polypyrrole-polyaniline electrode was prepared by electropolimerization pyrrole and aniline in sulphuric acid media containing pyrrole. Cholesterol oxidase has been immobilized on the surface of platinum / polypyrrole-polyaniline electrode. Determination of cholesterol was performed by means of oxidation of hydrogen peroxide liberated during the enzymatic reaction on the surface of the enzyme electrode at +0,70V (Ag/AgCl). The effects of pH and temperature on the response of the cholesterol biosensor were investigated. The linear working range of biosensor was 1,8.10-5 ? 5.10-5 M of cholesterol concentration. Value of KM and Vmax of immobilized enzyme were estimated respectively. Reuse number and storage stability were determined of the biosensor. Determination of cholesterol was carried out in biological fluid (in blood) by biosensor