Bio-Particle Sorting Employing Hydrodynamic Rectification in a Microfluidic Circuit

A microfluidic bio-particle sorter has been developed utilizing a concept that a microchannel network acts as a resistive circuit when a Newtonian fluid is continuously introduced into the network. By hydrodynamically rectifying the particle positions inside the microfluidic circuit, particles suspended in liquid are perfectly aligned onto one sidewall inside the microchannel, and then concentrated and sorted according to size. We used particles with diameter of 1~ 3 μm; they were concentrated 30~ 80-fold, and separated even when the difference in particle diameter was smaller than 1 μm. In addition, it was demonstrated that the distributed flow rates well corresponded to the theoretical values.