【摘要】 自行设计开发了一套便于与电泳芯片集成的一体式柱端安培检测池系统.该系统由整块透明有机玻璃精密加工而成,包括电泳芯片支架和安培检测池两部分,芯片可通过芯片插槽和不锈钢夹具固定在芯片支架上,各种检测用电极可直接通过螺母固定在安培检测池中.以100μmol/L的DA为模式分析物,分别采用直径为100、300和500μm的铂金圆盘电极与表观直径为240μm的碳纤维电极作为工作电极均在该装置上实现了良好组装和高灵敏检测.采用碳纤维工作电极对该系统的检测参数进行了优化.测试结果表明该系统在电化学清洗程序下连续六次测定100μmol/L多巴胺的峰电流相对标准偏差为3.2%,保留时间相对标准偏差为0.5%,DA的检测限为0.4μmol/L(按照S/N=3计).该系统体积小巧,测试稳定,检测灵敏度较高,工作电极更换方便,适合作为芯片电泳柱端安培检测通用平台.更多还原

【Abstract】 A set of integrated end-column amperometric detection system has been developed, onto which an electrophoresis microchip can be conveniently integrated. Finely machined by a piece of transparent organic glass, the system consists of an electrophoresis microchip platform and an amperometric detection reservoir, in which the microchip can be fixed onto the platform by microchip grooves and with stainless steel fixture. Each detection electrode can be directly fixed in the amperometric detection reservoir by screws and nuts. With dopamine as model analytes, we take platinum disc electrodes with different diameters of 100, 300 and 500 μm and a carbon fiber electrode with the diameter of 240 μm as working electrodes, all of which accomplish sensitive detection. The detection parameters of the system are optimized with the carbon fiber electrode. The detection results show that in the electrochemical cleaning procedure, the relative deviations of 3.2% and 0.5% for peak current and retention time respectively can be obtained for the successive detections of 100 μmol/L dopamine, and the limit of detection for dopamine can reach 0.4 μmol/L (S/N = 3). This system is small, but its performance of detection is stable and sensitive, and the replacement of its working electrodes is convenient, so it is very suitable as a universal platform of end-column amperomet-ric detection for electrophoresis microchip.更多还原