Highly Integrable Flow Regulator With Positive Gain

This letter presents a highly integrable geometry for microfluidic flow regulators with positive gain. The objective of integration requires membranes to be small in diameter and the total area of the device as reduced as possible. For this, a flexible material is needed, and polydimethylsiloxane (PDMS) was chosen, with a suitable fabrication process designed for it. However, the use of a material which is too flexible leads to partial or complete obstruction of the working channel when the device is operating due to an undesired deformation of some parts of the structure. A change on the internal geometry of the device was designed, changing the shape of one membrane from circular to pseudo-elliptical. The external dimensions are 4000 and 2000 μm. When compared to previous devices, the gain relative to working pressure is increased from 0.034 to 0.16 mL/(min · bar²) , and the flow regulation from 1 to 1.4 mL/min.