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.

Capillary and Microchip Electrophoresis

“…In the sponge-integrated device, an aqueous E-mail: kitagawa@hirosaki-u.ac.jp solution could be introduced into a whole microchannel within 70 s, only dripping to one reservoir, while improving the portability of MCE devices due to no need for an external pump. 17 Further developments in CE and MCE are expected for various analytical fields, including biological, clinical, environmental, industrial, and food analyses.…”

Analytical Chemistry by Electrophoresis

“…Capillary electrophoresis (CE) 6 and microchip electrophoresis (MCE) 7 enable automatic analysis, and MCE especially enables micro-total analysis. CE and MCE, which uses a micrometersized capillary and a microchannel, do not require large volume samples, and attain superior separation because of plug flow, suppression of convection, as well as heat dissipation.…”