Au-TiO_2纳米粒子修饰电极用于有机磷农药对硫磷的直接电化学检测的研究

Electrochemical sensor based on Au-doped TiO_2 nanoparticles for the direct detection of parathion

该文利用液相沉积法合成了金掺杂的二氧化钛复合纳米粒子(Au-TiO2),以壳聚糖为交联剂,制备了Au-TiO2复合纳米粒子修饰的电化学传感器,对有机磷农药对硫磷进行了检测。实验表明,Au-TiO2复合纳米粒子大的比表面积能够增加对底液中对硫磷的吸附量,提高检测的灵敏度;同时,该复合纳米粒子也能有效地促进电子传递,加快传感器的响应速度,提高电流响应。所制备的电化学传感器利用示差脉冲伏安法(DPV)在最优条件下对对硫磷进行了检测,检测范围为1.0～7.0×103ng/mL,检测限达到0.5ng/mL。

In this study, Au - doped TiO2 nanoparticles （NPs） were synthesized and used for fabrication of electrochemical sensor with Chitosan as a conjunct for the detection of nitroaromatic organophosphorus pesticide parathion which exhibits good redox activities at the electrode surface. The electrochemical characterization and cathodal stripping voltammetric performance of parathion were evaluated using Cyclic Voltammetric （CV） and Differential Pulse Voltammetric （DPV） ananlysis. Operational parameters, including the amount of nanoparticles and pH of the reaction medium have been optimized. Under the optimized condition, electrochemical sensor modified with Au - TiO2 NPs exhibited promising voltammetric performances. The voltammetric response was highly linear over the 1.0 - 7.0 χ 10^3 ng/mL parathion range examined, with a detection limit of 0.5 ng/mL.