Abstract:

The digital droplet microfluidic chip based on electrowetting technology is a platform that drives the movement of trace liquid by controlling the change of the charge at the solid-gas-liquid interface of the insulating layer on the electrode. It has been widely used for its flexible manipulation of biochemical samples. However, the traditional preparation of insulating and hydrophobic layers will lead to some problems. Here we propose a free-standing hydrophobic layer, which greatly improves the reliability of droplet driving. By preparing a free-standing hydrophobic film on a flat silicon wafer and laying it on the surface of a digital droplet microfluidic electrode, instead of directly depositing a dielectric layer on the electrode surface, some problems of the traditional method are improved.