Cholesterol amperometric biosensor based on cytochrome P450scc

A screen-printed enzyme electrode based on flavocytochrome P450scc (RtP450scc) for amperometric determination of cholesterol has been developed. A one-step method for RtP450scc immobilization in the presence Of glutaraldehyde or by entrapment of enzyme within a hydrogel of agarose is discussed. The sensitivity of the biosensor based on immobilization procedures of flavocytochrome P450scc by glutaric aldehyde is 13.8 nA muM(-1) and the detection limit is 300 muM with a coefficient Of linearity 0.98 for cholesterol in the presence of sodium cholate its detergent. The detection limits and the sensitivity of the agarose-based electrode are 155 muM and 6.9 nA muM(-1) with a linearity coefficient of 0.99. For both types of electrodes, the amperometric response to cholesterol in the presence of' detergent was rather quick (1.5-2 min). (C) 2003 Elsevier B.V. All rights reserved.