Microfluidic patterning of P-selectin for cell separation through rolling

We present a new method for label-free separation of cells by rolling on patterned P-selectin receptors. We patterned edges of P-selectin on a substrate using microfluidic channels and flowed a stream of cells and microspheres over the pattern at an angle to the patterns in a microfluidic device. The cells selectively interacted with P-selectin and were deflected from their path out of the flow stream by rolling on the patterned edges. This result provides proof-of-concept of separation and suggests that rolling on patterned receptors may be further developed into a simple, label- free system for separation of cells.