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...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 the model analyte,we take platinum disc electrodes with different diameters of 100 μm,300 μm and 500 μm and a carbon fiber electrode with the diameter of 240 μm as the working electrode,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 the peak current and retention time,respectively,can be obtained for the successive detections of 100 μM dopamine,and the limit of detection for dopamine can reach 0.4 μM(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 amperometric detection for electrophoresis microchips.展开更多
基金supporting from the National Natural Science Foundation of China (Grant Nos.20605018 & 20975106)Beijing Natural Science Foundation (Grant No.2072018)
文摘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 the model analyte,we take platinum disc electrodes with different diameters of 100 μm,300 μm and 500 μm and a carbon fiber electrode with the diameter of 240 μm as the working electrode,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 the peak current and retention time,respectively,can be obtained for the successive detections of 100 μM dopamine,and the limit of detection for dopamine can reach 0.4 μM(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 amperometric detection for electrophoresis microchips.