Abstract
A novel laminar-stream-based microfluidic system that can serve the function of motility-grated sperm separation was proposed. The working concept lies in the design of a curve-and-straight encountering flow system that controls the formation of matched parallel laminar streams to encourage sperms with high motility to swim across the curve-straight stream boundary lines for high efficient separation. Real physical experiments with animal semens have been carried out, and demonstrated that the system can effectively separate raw semen samples into mixed-immobile and mobile groups.