Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, Nanchang 330013, People's Republic of China.
Appl Biochem Biotechnol. 2012 Aug;167(7):2023-38. doi: 10.1007/s12010-012-9711-y. Epub 2012 May 29.
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.
抗坏血酸氧化酶（AO）作为一种具有生物活性的大分子，成功地固定在一种生物相容性的夹层型复合膜中，用于开发维生素 C（VC）生物传感器，并通过电流测定法对商业果汁中的 VC 含量进行了测定。生物相容性和导电性的聚（3,4-亚乙基二氧噻吩）复合膜和高稳定性和选择性的多壁碳纳米管-纳滤复合膜分别作为生物传感器的内、外膜。AO 分子被固定在这两种复合膜之间。所制备的生物传感器对 VC 的氧化表现出优异的生物电化学催化性能，具有快速的电流响应、低工作电位、高灵敏度、宽线性范围和低检测限。此外，还提出了生物传感器的工作机制，并对其动力学进行了讨论。此外，还评估了所制备的生物传感器的特异性、重现性和可行性。在商业果汁中 VC 测定的良好结果表明，所制备的生物传感器是电化学测定农业作物中 VC 的潜在候选者。内、外膜为固定生物活性物质提供了一个有前途的平台。
