Amperometric vitamin C biosensor based on the immobilization of ascorbate oxidase into the biocompatible sandwich-type composite film.
Ascorbate oxidase (AO), a biologically active macromolecule, was successfully immobilized into a biocompatible sandwich-type composite film for developing the vitamin C (VC) biosensor, and the content of VC in commercial juices was amperometrically determined. The biocompatible and conducting poly(3,4-ethylenedioxythiophene) composite film and highly stable and selective multiwalled carbon nanotubes -Nafion composite film were prepared as inner and outer films of biosensor. AO molecules were immobilized between these two composite films. The as-fabricated biosensor displayed an excellent bioelectrocatalytic performance towards the oxidation of VC, a fast current response, a low working potential, a high sensitivity, a wide linear range, and a low detection limit. Moreover, the working mechanism of the biosensor was proposed, and its kinetics was also discussed. In addition, the specificity, reproducibility, and feasibility of the as-fabricated biosensor were also evaluated. Good results of the VC determination in commercial juices indicated that the as-fabricated biosensor was a potential candidate for the electrochemical determination of VC in agricultural crops. Inner and outer films provided a promising platform for the immobilization of biologically active species.
Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, Nanchang 330013, People's Republic of China.
Yangping
Y
Wen
Jingkun
J
Xu
Ming
M
Liu
Dong
D
Li
Haohua
H
He
D001204:Ascorbate Oxidase / Q000378:metabolism*; D001205:Ascorbic Acid / Q000032:analysis*; D001628:Beverages / Q000032:analysis; D055162:Biocatalysis; D001672:Biocompatible Materials / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D028464:Cucurbita / Q000201:enzymology*; D004560:Electricity; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000378:metabolism*; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D010084:Oxidation-Reduction; D013499:Surface Properties
D001672:Biocompatible Materials; D004800:Enzymes, Immobilized; D001204:Ascorbate Oxidase; D001205:Ascorbic Acid