Biosensor for total cholesterol estimation using N-(2-aminoethyl)-3-aminopropyltrimethoxysilane self-assembled monolayer

Cholesterol oxidase (ChOx), cholesterol esterase (ChEt), and horseradish peroxidase (HRP) have been co-immobilized covalently on a self-assembled monolayer (SAM) of N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAPTS) deposited on an indium-tin-oxide (ITO) glass surface. These enzyme-modified (ChOx-ChEt-HRP/AEAPTS/ITO) biosensing electrodes have been used to estimate cholesteryl oleate from 10 to 500 mg dL(-1). The sensitivity, K-m value, and shelf-life of these ChEt-ChOx-HRP/AEAPTS/ITO biosensing electrodes have been found to be 124 nA mg(-1) dL, 95.098 mg dL(-1) (1.46 mmol L-1), and ten weeks, respectively. The ChEt-ChOx-HRP/AEAPTS/ITO bio-electrodes have been used to estimate total cholesterol in serum samples.