基于石墨烯-氧化锌复合物的乙酰胆碱酯酶生物传感器用于辛硫磷的测定

摘要

A highly sensitive electrochemical biosensor for phoxim determination was constructed by immobilizing acetylcholinesterase (AChE) onto the surface of a glassy carbon electrode modified by graphene-ZnO (GR-ZnO) nanocomposite film. The nanocomposite not only provided a biocompatible microenvironment to keep the bioactivity of AChE, but also exhibited a strong synergetic effect on improving the sensing properties of phoxim. The inhibition rate of phoxim was proportional to the logarithmic value of phoxim concentrations in the range of 1.0×10-11 to 1.0×10-6 mol/L,and the detection limit was 3.4 ×10-12 mol/L (S/N=3).%将乙酰胆碱酯酶(AChE)固定到石墨烯-氧化锌(GR-ZnO)纳米复合物修饰的玻碳电极表面,构建了一种用于辛硫磷检测的高灵敏电化学生物传感器.纳米复合物不仅为保持AChE的生物活性提供了适宜的微环境,并且对辛硫磷的传感性能的改善显示出强大的协同效应.抑制率与辛硫磷浓度的对数值在1.0× 10-11 mol/L到1.0× 10-6 mol/L范围内呈良好的线性关系,检测限为3.4×10-12 mol/L(S/N=3).