Plastic micropumps using ferrofluid and magnetic membrane actuation

This paper presents a simple and low-cost prototyping technology for the realization of integrated micropumps in polymethylmethacrylate (PMMA). The three-dimensional (3D) micropumps consist of stacks of structured PMMA layers, which are either realised with precision milling tools for the more complex parts, or fabricated using the powder blasting technique for channel-type structures. We integrate silicone membranes into the chip to realize check-valves or use dynamic diffuser valves. We use two different types of magnetic actuation external to the micropump: (i) an external magnet displaces a ferrofluid liquid plug that plays the role of a piston in a channel; (ii) an external coil actuates an integrated magnetic membrane, consisting of NdFeB magnetic powder in a polydimethylsiloxane (PDMS) matrix.