Rapid microfluidic mixer utilizing sharp corner structures

A novel microfluidic device for rapid and high-throughput fluid mixing is reported. The fluid mixing is based on the effect of a series of sharp corner structures in microchannel. The sharp corner induces fluid velocity components along the concentration gradient direction, stretching and folding the interfaces between different species. In addition, self-generated multilamellar fluid structures with small thickness are observed which significantly increase the interfacial contact area and reduce the diffusion length between different species. An optimal mixing efficiency of ~88.2% is achieved in less than 4.1 ms at the Reynolds number of 250. In comparison with other passive mixing methods, the present mixer is easy to fabricate and can effectively mix amounts of liquid in a very short time. With simple structure, high mixing efficiency and high throughput, this method can be potentially used in the fluid mixing in variety of lab-on-a-chip applications, such as analytic chemistry and clinic diagnosis.