氯化铵分子印迹电化学传感器的制备及性能研究

Preparation and performance study of ammonium chloride molecularlyimprinted electrochemical sensor

以氯化铵为模板分子,邻氨基苯酚为功能单体,通过电聚合法在玻碳电极表面制备了对氯化铵分子有特异性选择功能的分子印迹电化学传感器。当磷酸盐缓冲溶液pH为5.7,氯化铵与邻氨基苯酚的浓度比为5∶1,聚合圈数为20圈,洗脱时间为5min时制备的电化学传感器性能最优。采用循环伏安法、差分脉冲伏安法、电化学阻抗法及扫描电子显微镜对其性能及形貌进行测试和表征。结果表明,分子印迹电极的峰电流差值与氯化铵质量浓度[(0~46.67)×10^(-11)g/L]呈线性关系,线性方程为y=0.04x+0.18,相关系数R^(2)=0.9938,检出限为6.03×10^(-10)g/L。对加标水样进行测定,测得平均回收率为93.63%。

A molecularly imprinted electrochemical sensor with specific selective function for ammonium chloride was prepared on the surface of glassy carbon electrode by electropolymerization using ammonium chloride as template molecule and o-aminophenol as functional monomer.It was found that the performance of the prepared electrochemical sensor was the best under the condition of a phosphate buffer solution of 5.7 pH,a concentration ratio of ammonium chloride to o-aminophenol of 5∶1,20 polymerization cycles and 5 min elution time.The properties and morphology were characterized by cyclic voltammetry,differential pulse voltammetry,electrochemical impedance spectroscopy and scanning electron microscopy.The experimental results showed that the peak current difference of the imprinted electrode had a linear relationship with the concentration of ammonium chloride in the range of(0~46.67)×10^(-11)g/L,the linear equation was y=0.04x+0.18,correlation coefficient R^(2)was 0.9938,and detection limit was 6.03×10^(-10)g/L.The standard addition water sample was measured with the sensor,and the average recovery rate was 93.63%.