孔雀石绿分子印迹电化学传感器的制备与应用

Preparation and application of malachite green molecularly imprinted electrochemical sensor

目的建立分子印迹电化学传感器快速测定孔雀石绿的检测方法。方法首先采用一步合成法制备纳米复合材料十二磷钼杂多酸-聚多巴胺/还原氧化石墨烯(dodecaphosphomolybdenum heteropoly acid-polydopamine/reduced graphene oxide,PMo_(12)-PDA/RGO),并对其进行了红外光谱和扫描电子显微镜表征。然后以邻苯二胺(o-phenylenediamine,OPD)为功能单体、孔雀石绿(malachite green,MG)为模板分子,采用电聚合方法在PMo12-PDA/RGO修饰的电极表面制备印迹膜,采用循环伏安法进行洗脱,从而制备得到传感器。最后,对传感器制备和测定过程中的影响因素,如纳米材料的滴涂量、印迹圈数、洗脱剂类型、孵育时间和缓冲液pH进行优化。结果孔雀石绿溶液的浓度在0.1~15.0 nmol/L范围内与电流的变化值呈良好的线性关系,线性方程为ΔI=0.5647X+4.0024,r^(2)=0.9916。方法检出限为5.47×10^(-11) mol/L。加标回收率为95.74%~113.21%,相对标准偏差小于4.9%(n=3)。结论该传感器快速、灵敏,可用于养殖水样中痕量孔雀石绿的检测。

Objective To construct a method for rapid determination of malachite green(MG) by molecular imprinted electrochemical sensor.Methods Firstly,one-step synthesis method was used to prepare the nanocomposite material dodecaphosphomolybdenum heteropoly acid-polydopamine/reduced graphene oxide(PMo12-PDA/RGO),and it was characterized by infrared spectrum and scanning electron microscope.Then,using o-phenylenediamine(OPD) as the functional monomer and MG as the template molecule,the imprinted membrane was prepared on the surface of the PMo12-PDA/RGO modified electrode by electropolymerization,and washed by cyclic voltammetry.Finally,the influencing factors in the process of sensor preparation and determination,such as the amount of nanomaterials applied,the number of blotting circles,the type of eluent,the incubation time,and the pH of the PBS buffer were optimized.Results The concentration of MG solution had a good linear relationship with the change of current in the range of 0.1-15.0 nmol/L.The linear equation was ΔI=0.5647X+4.0024,r^(2)=0.9916.The limit of detection was 5.47×10^(-11) mol/L.The recoveries were 95.74%-113.21%,and the relative standard deviations were less than 4.9%(n=3).Conclusion The sensor is rapid,sensitive,which can be used for the determination of trace MG in aquaculture water samples.