title: Highly-sensitive cholesterol biosensor based on platinum-gold hybrid functionalized ZnO nanorods.
abstract: A novel scheme for the fabrication of gold/platinum hybrid functionalized ZnO nanorods (Pt-Au@ZnONRs) and multiwalled carbon nanotubes (MWCNTs) modified electrode is presented and its application for cholesterol biosensor is investigated. Firstly, Pt-Au@ZnONRs was prepared by the method of chemical synthesis. Then, the Pt-Au@ZnONRs suspension was dropped on the MWCNTs modified glass carbon electrode, and followed with cholesterol oxidase (ChOx) immobilization by the adsorbing interaction between the nano-material and ChOx as well as the electrostatic interaction between ZnONRs and ChOx molecules. The combination of MWCNTs and Pt-Au@ZnONRs provided a favorable environment for ChOx and resulted in the enhanced analytical response of the biosensor. The resulted biosensor exhibited a linear response to cholesterol in the wide range of 0.1-759.3 μM with a low detection limit of 0.03 μM and a high sensitivity of 26.8 μA mM(-1). The calculated apparent Michaelis constant K(M)(app) was 1.84 mM, indicating a high affinity between ChOx and cholesterol.
authors.affiliation: Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors.forename: Chengyan
authors.initials: C
authors.lastname: Wang
authors.forename: Xingrong
authors.initials: X
authors.lastname: Tan
authors.forename: Shihong
authors.initials: S
authors.lastname: Chen
authors.forename: Ruo
authors.initials: R
authors.lastname: Yuan
authors.forename: Fangxin
authors.initials: F
authors.lastname: Hu
authors.forename: Dehua
authors.initials: D
authors.lastname: Yuan
authors.forename: Yun
authors.initials: Y
authors.lastname: Xiang
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D002784:Cholesterol / Q000097:blood*; D002789:Cholesterol Oxidase / Q000737:chemistry; D055664:Electrochemical Techniques; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry; D005898:Glass; D006046:Gold / Q000737:chemistry*; D006801:Humans; D007700:Kinetics; D057230:Limit of Detection; D046529:Microscopy, Electron, Transmission; D043942:Nanotubes / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry; D056951:Photoelectron Spectroscopy; D010984:Platinum / Q000737:chemistry*; D055672:Static Electricity; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D004800:Enzymes, Immobilized; D037742:Nanotubes, Carbon; D010984:Platinum; D006046:Gold; D002784:Cholesterol; D002789:Cholesterol Oxidase; D015034:Zinc Oxide