喹乙醇印迹传感器的制备及其在喹噁啉类药物残留快检中的应用

以纳米银溶胶和纳米石墨烯为电极修饰材料，制备以喹乙醇为模板分子，邻氨基苯酚和间苯二酚为复合功能单体的一种新型快速检测喹噁啉类药物的印迹传感器。运用紫外光谱法选择最优功能单体，并研究模板分子与功能单体之间的作用形式和作用强度，结合电化学分析法优化制备条件并测定该印迹传感器的分析性能。在乙醇-0.4 mol/L NaOH溶液（3∶1，V/V）中洗脱20 min，实现模板分子的高效洗脱。以K3Fe(CN)6]作为电活性探针，通过响应电流变化对4 种喹噁啉类兽药含量进行间接测定。结果表明，该印迹传感器对喹乙醇具有较高的选择性和灵敏度，对其结构类似物也有特异吸附作用，样品加标平均回收率为89.05%～100.86%，相对标准偏差在1.03%～3.11%之间（n=5）。该传感器成功应用于动物源性食品中喹噁啉类促生长剂药物残留的灵敏快速检测。

Preparation and Application of Molecularly Imprinted Electrochemical Sensor for Rapid Detection of Quinoxaline Drug Residues

A novel molecularly imprinted electrochemical sensor for rapid detection of quinoxaline drugs was prepared using nanosized silver sol and graphene as electrode modification materials,olaquindox as template molecule,and o-aminophenol and resorcinol as composite functional monomers.Using ultraviolet(UV)absorption spectroscopy,we selected the optimal functional monomer,and studied the interaction between template molecule and functional monomer.The preparation conditions were optimized by electrochemical analysis and the analytical performance of the sensor was evaluated.The template molecules were efficiently eluted in 20 min with ethanol-0.4 mol/L NaOH aqueous solution(3:1,V/V).The contents of four quinoxaline growth promoters were indirectly determined by measuring changes in response current with K₃Fe(CN)₆]as electroactive probe.The results showed that the sensor displayed high sensitivity and selectivity to olaquindox,and could also specifically adsorb its structural analogues;the recoveries of spiked samples were between 89.05%and 100.86%with relative standard deviations(RSDs)of 1.03%–3.11%(n=5),and the sensor was successfully applied to sensitive and rapid detection of quinoxaline growth promoter residues in animal origin foods.