新诺明分子印迹传感器的制备及应用研究

Preparation and Its Application of Sulfamethoxazole Molecularly Imprinted Polymer Sensor

目的以吡咯为单体在玻碳电极表面电聚合一种新诺明分子印迹膜。方法研究了聚吡咯、新诺明浓度、扫描圈数及扫描速率对印迹膜制备的影响，并探讨检测液的pH值、乙腈与水的体积比对响应电流的影响。采用循环伏安法及电化学交流阻抗技术对分子印迹膜进行表征。结果在最佳实验条件下新诺明的浓度在2．50×10^-5～7．50×10^-4mol·L^-1及7．50×10^-4～2．00×10^-3mol·L^-1内时，差分脉冲伏安法的峰电流响应值呈现线性关系（线性相关系数分别为0．9958和0．99671，检出限（S／N=3）为2．80×10^-6mol·L^-1。结论印迹电极也显示出较好的选择性、重复性、稳定性。将此印迹传感器对复方新诺明药品中磺胺甲嗯唑的含量进行了测定，回收率在94．2％～105．0％。

OBJECTIVE To electroploymerize a molecularly imprinted polymer（MIP） film for sulfamethoxazole detection on a glassy carbon electrode by the use of pyrrole monomer. METHODS The effects of sulfamethoxazole concentration, polypyrrole concentration, number of scan cycle and scan rate on the MIP film were investigated respectively. The effects of pH value and acetonitrile-water ratio of detection liquid on response current were also explored. The imprinted film was characterised by electrochemical impedance spectroscopy（EIS） and cyclic voltammetry （CV）. RESULTS The results indicated the DPV peak current showed a linear dependence on the sulfamethoxazole concentration in the ranges of 2.50 × 10^-5-7.50× 10^-4 mol·L^-1 and 7.50× 10^-4-2.00× 10^-3 mol·L^-1 of sulfamethoxazole（each correlation coefficient of 0.995 8 and 0.996 7, respectively） with the detection limit （S/N=3） of 2.80×10^-6 mmol·L^-1, under the optimal experimental conditions. CONCLUSION This MIP film electrode also displayed good selectivity and reproducibility and stability. The prepared sensor was applied to the determination of sulfamethoxazle in Paediatric Compound Sulfamethoxazole Tablet samples with recovery ranging from 94.2% to 105.0%.