NANOMISENE Lab, LR16CRMN01, Centre for Research on Microelectronics and Nanotechnology CRMN of Sousse, Technopark of Sousse B.P. 334, Sahloul, 4034 Sousse, Tunisia; University of Sousse, High School of Sciences and Technology of Hammam Sousse, 4011 Hammam Sousse, Tunisia.
Department of Chemistry, Faculty of Sciences and Technology, University of Coimbra, 3004-535 Coimbra, Portugal.
Talanta. 2018 Jul 1;184:388-393. doi: 10.1016/j.talanta.2018.03.031. Epub 2018 Mar 13.
A novel and simple biosensor for the determination of bisphenol A (BPA) based on xanthine oxidase (XOD) enzymatic inhibition has been developed. The biosensor was prepared from xanthine oxidase immobilised by crosslinking with glutaraldehyde, with hypoxanthine as enzyme substrate, and was successfully applied to the determination of BPA using fixed potential amperometry. Biosensor performance was optimised with respect to the applied potential, influence of pH of the electrolyte solution, XOD loading and the substrate concentration. The enzyme inhibition mechanism was evaluated from Cornish-Bowden plus Dixon plots and was found to be reversible and competitive with an apparent inhibition constant of 8.15 nM. Under optimised conditions, the determination of BPA can be achieved in the linear range up to 41 nM with a detection limit of 1.0 nM, which is equal to the lowest reported in the literature, with very good repeatability and reproducibility. The selectivity of the biosensor was evaluated by performing an interference study and found to be excellent; and stability was investigated. It was successfully applied to the detection of BPA in mineral water and in river water.
基于黄嘌呤氧化酶（XOD）酶抑制作用，开发了一种用于测定双酚 A（BPA）的新型简单生物传感器。生物传感器是通过戊二醛交联固定化黄嘌呤氧化酶，以次黄嘌呤作为酶底物制备的，并成功应用于固定电位电流安培法测定 BPA。通过对施加的电势、电解质溶液 pH 值、XOD 负载和底物浓度的影响，对生物传感器的性能进行了优化。通过 Cornish-Bowden 加 Dixon 图评估了酶抑制机制，发现该机制是可逆的，且具有竞争性，表观抑制常数为 8.15 nM。在优化条件下，BPA 的测定可在 41 nM 的线性范围内进行，检测限为 1.0 nM，与文献中报道的最低值相当，具有非常好的重复性和再现性。通过进行干扰研究评估了生物传感器的选择性，发现其非常出色；并研究了其稳定性。该生物传感器成功应用于矿泉水和河水的 BPA 检测。
