Micro-pressure sensor made of conductive PDMS for microfluidic applications

We report on results of fabrication and characterization of a conductive gel based pressure sensor which can be easily integrated into the commonly used microfluidic devices. The gel elements of the sensor are obtained by casting a viscous mixture of polydimethylsiloxane (PDMS) and metal powders on a patterned template. After solidification, the gel becomes conductive, showing piezoresistive effects that can be used for low pressure sensing. Our fabrication process of the gel elements is fully compatible to the integration requirement of multi-functional PDMS devices and the fabricated pressure sensors can be repeatedly used with direct current readout. (C) 2009 Elsevier B.V. All rights reserved.