Abstract
Nanostructured zinc oxide (nano-ZnO) film has been fabricated onto indium tin oxide (ITO) containing preferred (002) plane and 10 nm crystallite size using sol-gel technique for immobilization of cholesterol oxidase (ChOx). Electrochemical response of ChOx/nano-ZnO/ITO bioelectrode determined as a function of cholesterol concentration using cyclic voltammetry technique reveals improved detection range (5-400 mg/dl), low detection limit (0.5 mg/dl), fast response time (10 s), sensitivity
(
0.059
μ
A
/
mg
dl
−
1
cm
−
2
)
, and low value (0.98 mg/dl) of Michaelis-Menten constant
(
K
m
)
. It is shown that nano-ZnO film provides better environment and enhanced electron transfer between ChOx and electrode.