The continuous amperometric assay for determining total cholesterol in human serum was based on incorporating cholesterol ester hydrolase, cholesterol oxidase and peroxidase in enzyme reactors. The enzyme reactors were prepared by colvalent bonding of...
The continuous amperometric assay for determining total cholesterol in human serum was based on incorporating cholesterol ester hydrolase, cholesterol oxidase and peroxidase in enzyme reactors. The enzyme reactors were prepared by colvalent bonding of enzyme using glutaraldehyde to the long chain alkylamine silanized controlled-pore glass support. The hydrogen peroxide coupled with ferrocyanide ion in the presence of peroxidase was oxidized to produce ferricyanide ion that was detected at a glassy carbon working electrode with applied potential of -50 mV vs. Ag/AgCl reference electrode. The ferricyanide ion was stoichiometrically related to the total cholesterol concentration. The optimal conditions were as follows; flow rate of carrier solution(3.0 x 1O^(-2) M K_(4)Fe(CN)_(6) + Triton X-100 2.0% + 0.10 M phosphate buffer of pH 7.3), 0.30 ml/min; injection volume of sample solution, 20 μl.