Matharu Zimple, Sumana G, Arya Sunil K, Singh S P, Gupta Vinay, Malhotra B D
Biomolecular Electronics and Conducting Polymer Research Group, National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi-110012, India.
Langmuir. 2007 Dec 18;23(26):13188-92. doi: 10.1021/la702123a. Epub 2007 Nov 15.
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.
胆固醇氧化酶（ChOx）已通过戊二醛（Glu）化学法与制备在氧化铟锡（ITO）涂层玻璃板上的聚苯胺（PANI）-硬脂酸（SA）的朗缪尔-布洛杰特（LB）单分子层共价连接。这些ChOx/Glu/PANI-SA LB膜/ITO电极分别通过傅里叶变换红外光谱（FT-IR）、循环伏安法和扫描电子显微镜进行了表征。使用线性扫描伏安法（LSV）对这些生物电极进行响应测量的结果表明，在25至400 mg/dL的胆固醇浓度范围内呈线性，灵敏度为88.9 nA mg⁻¹ dL。生物电极的线性回归分析显示，标准偏差和相关系数分别为0.737 μA和0.9988。这些生物电极固定化酶的米氏常数低值为1.21 mM，表明PANI-SA LB膜中ChOx与胆固醇之间的相互作用增强。
