title: Amperometric biosensor for hydrogen peroxide based on horseradish peroxidase onto gold nanowires and TiO₂ nanoparticles.
abstract: An electrochemical biosensor for determination of hydrogen peroxide (H(2)O(2)) was fabricated, based on the electrostatic immobilization of horseradish peroxidase (HRP) with one-dimensional gold nanowires (Au NWs) and TiO(2) nanoparticles (nano-TiO(2)) on a gold electrode. The nano-TiO(2) can give a biocompatible microenvironment and compact film, and the Au NWs can provide fast electron transferring rate and greatly add the amount of HRP molecules immobilized on the electrode surface. Au NWs were characterized by ultraviolet-visible spectra and transmission electron microscope. The electrode modification process was probed by cyclic voltammetry and electrochemical impedance spectroscopy. Chronoamperometry was used to study the electrochemical performance of the resulting biosensor. Under optimal conditions, the linear range for the determination of H(2)O(2) was from 2.3 × 10(-6) to 2.4 × 10(-3) M with a detection limit of 7.0 × 10(-7) M (S/N = 3). Moreover, the proposed biosensor showed superior stability and high sensitivity.
authors.affiliation: Chongqing Key Laboratory of Analytical Chemistry, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors.forename: Huaan
authors.initials: H
authors.lastname: Zhong
authors.forename: Ruo
authors.initials: R
authors.lastname: Yuan
authors.forename: Yaqin
authors.initials: Y
authors.lastname: Chai
authors.forename: Wenjuan
authors.initials: W
authors.lastname: Li
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: Chengyan
authors.initials: C
authors.lastname: Wang
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D004563:Electrochemistry / Q000379:methods; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D006046:Gold / Q000737:chemistry*; D006735:Horseradish Peroxidase / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000032:analysis* / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D053770:Nanowires / Q000737:chemistry* / Q000648:ultrastructure; D012680:Sensitivity and Specificity; D014025:Titanium / Q000737:chemistry*
chemical_list: D004800:Enzymes, Immobilized; C009495:titanium dioxide; D006046:Gold; D006861:Hydrogen Peroxide; D014025:Titanium; D006735:Horseradish Peroxidase