Polydimethlsiloxane (PDMS) microchannel with trapping chamber for BioMEMS applications

This study presents fabrication and simulation of a microchannel for BioMEMS applications. The basic construction of this microfluidics channel consists of an inlet and an outlet, a microchannel for transporting continuous fluid flow and a trapping chamber as mean of trapping and separating the intended biological cells. The microchannel is constructed using polydimethlsiloxane (PDMS) using replica molding technique from SU-8 mold. The flow characteristics and the pressure drop experienced by microchannel have been modeled and simulated using Finite Element Analysis (FEA). The simulation results revealed a linear relationship of velocity magnitude and pressure drop with volumetric flow rate in the range of 0.5 to 1000 μL/min. Furthermore, the velocity streamlines indicated a laminar fluid characteristic is maintained in the microchannel flow at maximum volumetric flow rate of 1000 μL/min. Pressure drop is a vital parameter in a microchannel design due to the bonding limit between the PDMS microchannel and its substrate. In this work, a maximum pressure drop of 14.8 kPa is developed at maximum volumetric flow rate of 1000 μL/min. The pressure drop is in a safe limit for PDMS microchannel bonded with PDMS layer substrate operation.