Fabrication of a novel liquid metal microelectrode in microfluidic chip

Electrokinetics is a good fluid control tool in microfluidics and usually microelectrodes play important roles in such approach such as generating a desired electric field. Though the fabrication of two-dimensional (2D) microelectrodes has been relatively mature, they cannot generate uniform electric field in space. Three-dimensional (3D) microelectrodes developed more recently may solve the problem, however the fabrication process is usually complicated and requires micro-alignment platform. Non-toxic liquid metal is a good material for making electrodes that has been introduced into microfluidics. It can be injected directly into a microchannel to form an electrode, but its special physical properties make the injection process complex and difficult to control. In this study, we investigated an optimized manufacturing method of liquid metal microelectrode in a microchip by numerical analysis and experimental study. High quality microelectrodes on morphology and stability were successfully fabricated. A fluorescent enrichment experiment was performed using the developed microelectrode in a microfluidic chip. The result shows that the optimized fabrication method of microelectrode in this study provides a promising way for high quality and good performance liquid metal microelectrode formation, and paves the way for its versatile applications.

Automated summary

Electrokinetics is a useful tool in microfluidics for fluid control, with recent developments in three-dimensional microelectrodes potentially solving issues with uniform electric field generation. Non-toxic liquid metal has been introduced as a material for electrodes in microfluidics, but its complex injection process requires optimization. This study successfully developed an optimized manufacturing method for liquid metal microelectrodes in microchips, paving the way for versatile applications of high-quality microelectrodes.