对硫磷在单壁碳纳米管/金-四氧化三铁纳米粒子复合材料修饰电极上的电化学响应及其测定

制备了单壁碳纳米管/金-四氧化三铁纳米粒子复合材料修饰玻碳电极,用循环伏安法研究了对硫磷在该电极上的电化学行为。该电极对对硫磷具有较好的富集和催化特性,在优化条件下,对硫磷的浓度与其峰电流在2.0×10-9～1.0×10-6 mol/L范围内呈线性关系,其检出限为1.0×10-9 mol/L。对1.0×10-7 mol/L的对硫磷溶液平行测定9次的RSD为3.9%(n=9)。用该电极对不同蔬菜样品中的对硫磷进行测定,平均回收率在96.0%～105.5%之间,相对标准偏差在3.3%～3.9%之间。

Sensitive electrochemical response and analysis of parathion at a SWNT/Au-Fe3O4 modified electrode

A SWCNTs/Au-Fe3O4 NPs/CHIT modified electrode was fabricated with a glassy carbon electrode(GCE) coated by composite of single-walled carbon nanotubes(SWCNTs),Au-Fe3O4 nanoparticles(Au-Fe3O4 NPs) and Chitosan(CHIT).The electrochemical behaviors of parathion at the electrode were investigated with cyclic voltammetry.The electrode showed good electrocatalysis and accumulation for parathion.Under the optimized conditions,the peak current was linear to parathion concentration in the range of 2.0×10-9 to 1.0×10-6 mol/L.The detection limit was 1.0 ×10-9mol/L.The relative standard deviation(RSD) for 1.0×10-7 mol/L parathion was approximately 3.9%(n=9).This electrode was applied to detecting parathion in different vegetables,the average recoveries were from 96.0% to 105.0% and RSDs were 3.3%～3.9%.