Design and microfabrication of an electromagnetically-actuated soft-polymer micropump

A comprehensive review of current micropump technologies is presented with particular emphasis on drug delivery applications. The working principles, actuation strategies and configurations, material selection and relevant fabrication techniques are described and discussed. Based on these studies, a compact valveless micropump driven by an electromagnetic actuator is presented. This micropump features a pair of micro diffuser and nozzle elements to rectify the fluid flow and an elastic magnetic membrane to regulate the pressure in the enclosed fluid chamber. To understand the behaviors of the micropump, an analytical model was established to describe the critical relationship between the flow rate and design parameters of the pump, which include the nozzle and diffuser, material properties of the working fluids and the elastic membrane.;The construction of the micropump was based on high aspect-ratio UV lithography and polydimethylsiloxane (PDMS) elastomer micromolding soft fabrication techniques. The performance of two micropump prototypes made entirely of complete PDMS polymer was evaluated and characterized at different working conditions (such as variations in current, excitation frequency, backpressure and working fluids). Furthermore, the resonant frequency of the micropump was identified experimentally through the coupling effects of the fluid. Finally, a comparison study between the proposed design and previously reported ones in the literature was conducted for the purpose of establishing a reference that allows for specific type of micropump to be selected for certain applications.;There are several advantages associated with this type of micropump. To begin, its planar structure without mechanical moving parts for fluid directing is useful in transport of particle-laden fluid. The micropump is small, lightweight and very suitable for integration with other microfluidic systems. The low power consumption and stable continuous flow renders this type of micropump a potential for various portable medical applications.