title: A third-generation hydrogen peroxide biosensor based on horseradish peroxidase immobilized in a tetrathiafulvalene-tetracyanoquinodimethane/multiwalled carbon nanotubes film.
abstract: A new third-generation biosensor for H(2)O(2) assay was developed on the basis of the immobilization of horseradish peroxidase (HRP) in a nanocomposite film of tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ)/multiwalled carbon nanotubes (MWCNTs) modified gold electrode. The prepared HRP/TTF-TCNQ/MWCNTs/Au electrode was used for the bioelectrocatalytic reduction of H(2)O(2), with a linear range from 0.005 to 1.05 mM and a detection limit of 0.5 microM for amperometric sensing of H(2)O(2). In addition, a novel method on the basis of electrochemical quartz crystal microbalance (EQCM) measurements was proposed to determine the effective enzymatic specific activity (ESA) of the immobilized HRP for the first time, and the ESA was found to be greater at the TTF-TCNQ/MWCNTs/Au electrode than that at the MWCNTs/Au or TTF-TCNQ/Au electrode, indicating that the TTF-TCNQ/MWCNTs film is a good HRP-immobilization matrix to achieve the direct electron transfer between the enzyme and the electrode.
authors.affiliation: Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research (Ministry of Education of China), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China.
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Cao
authors.forename: Xueqin
authors.initials: X
authors.lastname: Jiang
authors.forename: Qingji
authors.initials: Q
authors.lastname: Xie
authors.forename: Shouzhuo
authors.initials: S
authors.lastname: Yao
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006571:Heterocyclic Compounds / Q000737:chemistry*; D006735:Horseradish Peroxidase / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000032:analysis*; D008567:Membranes, Artificial; D008839:Microelectrodes; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D009570:Nitriles / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D004800:Enzymes, Immobilized; D006571:Heterocyclic Compounds; D008567:Membranes, Artificial; D037742:Nanotubes, Carbon; D009570:Nitriles; C013703:tetracyanoquinodimethane; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase; C063887:tetrathiafulvalene