低电压电泳芯片及其在生化样品分析中的应用

为了解决微流控电泳芯片集成化问题,设计并制作出一种具有管道两侧微阵列电极结构的硅-PDMS复合低电压电泳芯片.通过电路控制程序在微侧壁阵列电极上施加交替循环的低电压,以实现芯片微管道中低电压电泳过程;并对硅-PDMS芯片的电绝缘性、伏安曲线及电渗流等性能进行了测试和评价.以pH为10.0、10mmol/L的硼砂作为缓冲体系,分离场强150V/cm、切换时间3s的条件下,完成了10-4mol/L的苯丙氨酸和精氨酸的低电压电泳分离,分离度达1.6,实现了两种氨基酸的完全分离.在此基础上,将系统用于牛血清白蛋白和α-乳白蛋白的分离,并初步实现了该两种蛋白质的芯片电泳分离.

Low-Voltage-Driven Electrophoresis Microchip and Its Application in Biochemical Analysis

A new SOI-PDMS hybrid low-voltage-driven electrophoresis microchip with integrated array-electrodes on the microchannel sidewall was designed and constructed. A specially integrated circuit(IC) was proposed to power a DC voltage to particular sets of these electrode pairs in a controlled sequence so that the moving electric field could be formed, and the low-voltage-driven electrophoresis could be realized in the microchannel. Using the mini laser-induced fluorescence (LIF) as detection mode, a set of low-voltage-driven electrophoresis separating and detecting system was finally established. The electrical properties of the microchip, such as insulation, volt-ampere characteristic curve and electroosmotic flow, were tested and evaluated. Fluorescein-5(6)-isothiocyanate (FITC) labeled 10-4 mol/L arginine and phenylalanine were successfully separated under the optimal conditions, including 10 mmol/L borax buffer (pH=10), 150 V/cm separation electric field strength and switching time of 3 s. The separation was completed with a resolution of 1.6. Finally, the system was applied to the protein analysis, and the separation of BSA and α-lactoglobulin from their mixture was realized preliminarily by low-voltage-driven electrophoresis on microchip.