还原氧化石墨烯-纳米金修饰的分子印迹传感器选择性检测水与牛奶中盐酸洛美沙星

Selective Determination of Lomefloxacin Hydrochloride in Water and Milk Using a Reduced Graphene Oxide-Au NPs Modified Molecular Imprinting Sensor

开发了一种基于金电极表面修饰还原氧化石墨烯(rGO)-纳米金(AuNPs)的分子印迹电化学传感器,用于选择性测定盐酸洛美沙星。AuNPs-rGO纳米复合材料通过电化学还原氧化石墨烯(GO)和HAuCl_4修饰到金电极表面,印迹的聚邻苯二胺和间苯二酚膜嵌在AuNPs-rGO表面作为功能单体选择性识别盐酸洛美沙星。以K_3[Fe(CN)_6]为氧化还原探针,运用循环伏安法(CV)和差分脉冲法(DPV)表征了印迹传感器的电化学性能。结果表明印迹传感器对洛美沙星的选择性高,而引入的还原氧化石墨烯-纳米金(Au NPsrGO)复合材料显著提高了传感器的电子传输速率和灵敏度。最佳条件下,氧化还原探针的DPV峰电流对0.01~1.0μmol/L浓度范围内洛美沙星呈良好的线性,检出限(S/N=3)为3.0 nmol/L。方法用于西江水和牛奶中盐酸洛美沙星的检测,精密度(RSD≤6.2%)和回收率(88.0%~102%)满意。

A molecularly imprinted electrochemical sensor based on gold electrode decorated with reduced graphene oxide(rGO)incorporated gold nanoparticles(AuNPs)was developed for the selective determination of lomefloxacin hydrochloride(LMX).The AuNPs-rGO nanocomposites were modified onto the gold electrode through the electrochemical reduction of graphene oxide and HAuCl 4.The imprinted poly-o-phenylenediamine(o-PD)and m-dihydroxybenzene(m-DB)membrane,which was embedded in AuNPs-rGO surface,functioned as a selective recognition element for LMX.The electrochemical behaviors of the imprinted sensor were characterized by cyclic voltammetry(CV)and differential pulse voltammetry(DPV)using K 3[Fe(CN)6]as the redox probe.The results showed that the imprinted sensor displayed a high selectivity for LMX,and the introduced AuNPs-rGO composites significantly enhanced the electronic transmission and sensitivity.Under the optimal conditions,the DPV peak currents of the redox probe were linear with LMX concentrations in the range of 0.01-1.0μmol/L,with a detection limit of 3.0 nmol/L(S/N=3).The method was applied in the determination of LMX in Xijiang water and milk samples with a satisfactory precision(RSD≤6.2%)and acceptable recoveries(88.0%-102%).