Passive Microfluidic Valve with Reduced Threshold Pressure

Microfluidic systems open new possibilities in chemistry, biology, and medicine. A key component of microfluidic networks is a valve that governs the flow. Passive planar valve needs no power source and is easy to fabricate. It consists of a movable flap and a fixed stopper. Backflow pushes the flap to the stopper and closes the channel. During fabrication, the flap is typically fixed at three sides, which makes it stiff and increases the threshold pressure. In this paper, fabrication technology is proposed to make a more compliant flap with two fixed sides. Operation of the valve is simulated and demonstrated experimentally. Threshold pressure is reduced by 2.5 times in comparison with conventionally fabricated valve.