Measurement of fluid pressure in microchannels

The measurement of fluid pressure in microfluidics is difficult. The amount of fluid required to fill the ‘dead volume’ of conventional pressure sensors can be orders of magnitude larger than the actual fluid volume in a microfluidic device. In the present study, we use an enhanced servo-nulling pressure measurement system (SNPMS) which enables pressure measurements in microchannels. The new SNPMS is a substantial improvement over an old servo-nulling technology which, to the authors’ best knowledge, has never been used in microfluidic research so far. The SNPMS is tested in a microdevice for studying blood flow with a channel size of 7.5μm.