Amperometric determination of cholesterol in serum with use of a renewable surface peroxidase electrode

A sensitive modified carbon paste electrode for the direct determination of cholesterol is described. Both cyclic voltammetric and chronoamperometric techniques are used. The electrode was modified with hydroxymethyl ferrocene and horseradish peroxidase. Cholesterol oxidase and cholesterol ester hydrolase are used in solution. The measured current is linear with cholesterol concentration in the range 1 × 10−6 to 1.5 × 10−4 M. The measuring time is 30 s.