title: An amperometric biosensor based on ascorbate oxidase immobilized in poly(3,4-ethylenedioxythiophene)/multi-walled carbon nanotubes composite films for the determination of L-ascorbic acid.
abstract: An amperometric L-ascorbic acid (AA) biosensor fabricated by immobilizing ascorbate oxidase (AO) in poly(3,4-ethylenedioxythiophene) (PEDOT) and multi-walled carbon nanotubes (MWCNTs) composite films was reported for the first time. The entrapment of AO in PEDOT/MWCNTs composite films was performed during an electrochemical polymerization process. The influence of various experimental conditions was examined for determining the optimum analytical performance. The response of the biosensor towards AA under the optimized conditions is linear from 0.05 to 20 mM with a detection limit of 15 µM (S/N = 3). The biosensor shows a response time of 20 s and a sensitivity of 23.95 mA M(-1) cm(-2). The apparent Michaelis-Menten constant (K(m)) and apparent activation energy (E(a)) are 19.5 mM and 21 kJ mol(-1), respectively. Moreover, the biosensor exhibits good anti-interferent ability, good reproducibility and remarkable storage stability.
authors.affiliation: Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, Nanchang, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Liu
authors.forename: Yangping
authors.initials: Y
authors.lastname: Wen
authors.forename: Jingkun
authors.initials: J
authors.lastname: Xu
authors.forename: Haohua
authors.initials: H
authors.lastname: He
authors.forename: Dong
authors.initials: D
authors.lastname: Li
authors.forename: Ruirui
authors.initials: R
authors.lastname: Yue
authors.forename: Guodong
authors.initials: G
authors.lastname: Liu
mesh_terms: D001204:Ascorbate Oxidase / Q000737:chemistry* / Q000378:metabolism; D001205:Ascorbic Acid / Q000032:analysis*; D015374:Biosensing Techniques; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000737:chemistry*; D004563:Electrochemistry; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008567:Membranes, Artificial; D015394:Molecular Structure; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010084:Oxidation-Reduction; D011108:Polymers / Q000737:chemistry*; D015203:Reproducibility of Results
chemical_list: D019086:Bridged Bicyclo Compounds, Heterocyclic; D004800:Enzymes, Immobilized; D008567:Membranes, Artificial; D037742:Nanotubes, Carbon; D011108:Polymers; C121383:poly(3,4-ethylene dioxythiophene); D001204:Ascorbate Oxidase; D001205:Ascorbic Acid