A Novel Solution-auto-introduction Electrophoresis Microchip Based on Capillary Force

Abstract

A novel solution-auto-introduction electrophoresis microchip based on capillary force aimed at improving portability is proposed in this paper. Two kinds of materials with micropores, poly(vinyl alcohol) (PVA)-sponge and nano-sponge, were employed as suction pumps that realized the introduction of a running buffer into the reservoirs. The surfaces of the microchannels in the microchips were modified by PVA to improve the moving velocity of the running buffer and the detection performance of the microchip. The introduction velocity of a running buffer in the PVA-coated microchannels was increased by two times compared with that in the native microchannels. The electrophoresis detection performance of several microchips composed of different microchannels and suction materials were evaluated comparatively. The results indicated that the surface coating of PVA can significantly improve the repeatability of the detection results by 20 – 40%, and the noise of the detected signals in the PVA-coated microchips is much lower than that in the native microchips. The proposed solution-auto-introduction electrophoresis microchip is a successful attempt that completely avoids the external connectors to accomplish the auto-introduction of running buffer. The solution-auto-introduction method provides a new train of thought for portable detection instruments with electrophoresis microchips in the future.