Polyaniline Langmuir-Blodgett film based cholesterol biosensor.
Cholesterol oxidase (ChOx) has been covalently linked to Langmuir-Blodgett (LB) monolayers of polyaniline (PANI)-stearic acid (SA) prepared onto indium-tin-oxide (ITO) coated glass plates via glutaraldehyde (Glu) chemistry. These ChOx/Glu/PANI-SA LB film/ITO electrodes have been characterized by FT-IR, cyclic voltammetry, and scanning electron microscopy, respectively. The results of response measurements carried out on these bioelectrodes using linear sweep voltammetry (LSV) reveal linearity from 25 to 400 mg/dL of cholesterol concentration with sensitivity of 88.9 nA mg(-1) dL. The linear regression analysis of bioelectrode reveals standard deviation and correlation coefficient of 0.737 microA and 0.9988, respectively. The low value of the Michaelis-Menten constant of these bioelectrodes obtained as 1.21 mM for the immobilized enzyme indicates increased interaction between ChOx and cholesterol in the PANI-SA LB film.
Matharu
Zimple
Z
Biomolecular Electronics and Conducting Polymer Research Group, National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi-110012, India.
Sumana
G
G
Arya
Sunil K
SK
Singh
S P
SP
Gupta
Vinay
V
Malhotra
B D
BD
D000814:Aniline Compounds / Q000737:chemistry*; D015374:Biosensing Techniques; D002784:Cholesterol / Q000032:analysis*; D002789:Cholesterol Oxidase / Q000737:chemistry; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry; D007700:Kinetics; D017550:Spectroscopy, Fourier Transform Infrared
D000814:Aniline Compounds; D004800:Enzymes, Immobilized; C416807:polyaniline; D002784:Cholesterol; D002789:Cholesterol Oxidase