多巴胺分子印迹电极的制备及其应用于人体尿液中多巴胺的分析检测

Preparation of Molecularly Imprinted Electrode and Its Application in the Analysis and Detection of Dopamine

以多巴胺(DA)为模板分子,吡咯为功能单体,构建特异性识别多巴胺的分子印迹电极,对所形成的分子印迹膜进行了表征。对缓冲溶液的p H值、洗脱剂的比例、洗脱时间、模板分子浓度等条件进行优化,最终在pH为6.2,洗脱剂甲醇∶水=3:1(V/V),洗脱时间3 min,模板分子浓度8μg·mL^(-1)条件下构建电化学传感器。此电化学传感器在多巴胺浓度为0.5~10μg·mL^(-1)范围内线性拟合良好,相关系数R^(2)=0.990 59,检测限(LOD)为0.1μg·mL^(-1)。用于检测人体尿液中多巴胺的含量,检测过程样品无需洗脱,加标回收率为92.1%~103.2%,相对标准偏差(RSD)小于3%。

In this paper,a molecularly imprinted electrochemical sensor for specific recognition of dopamine(DA)was constructed with dopamine as template molecule and pyrrole as functional monomer,and the molecularly imprinted mem⁃brane was characterized.The pH value of buffer solution,the proportion of eluent,elution time,template molecular con⁃centration and other conditions were optimized.Finally,The electrochemical sensor was constructed under the condition pH 6.2,eluent methanol∶water=3∶1(V/V),elution time 3 min,template molecular concentration 8μg·mL^(-1).The linear fitting is good in the range of dopamine concentration 0.5~10μg·mL^(-1),the correlation coefficient R^(2)=0.99059,and the limit of detection(LOD)is 0.1μg·mL^(-1).It is used to detect the content of dopamine in human urine.No elution is re⁃quired for samples in the detection process.The recovery rate is 92.1%~103.2%,and the relative standard deviation(RSD)is less than 3%.