Bi-directional control systems for microfluids

A bi-directional microfluid control system was developed both numerically and experimentally in this work. This pneumatic system is an on-chip planar structure without moving parts and does not require microfabricated heaters or electrodes. The pumping actuation is introduced to the microchannel fabricated in-chip by blowing an airflow through the device. The tunable parameters for adjusting the performance of pumping were the location of the inlet channel and the velocity of the airflow. The driving module was fabricated on PMMA and its feasibility was examined experimentally. A droplet of water in the microchannel can move forward, backward and stop under control of the driving module. The driving system is therefore particularly suited to micro devices for biochemical analysis.