Miniaturized PMMA ball-valve micropump with cylindrical electromagnetic actuator
We have fabricated and characterized a reciprocating poly(methylmetacrylate) (PMMA) ball-valve micropump actuated with a miniaturized cylindrical electromagnetic circuit. By finite element calculations, we have optimized the structure of the electromagnet that actuates a rare-earth permanent magnet embedded in a poly(dimethylsiloxane) (PDMS) pumping membrane. Powder blasting and conventional micromachining techniques are used for micropatterning the PMMA layers forming the microfluidic circuit. The self-priming ball-valve micropump exhibits a backpressure up to 35 kPa; water is pumped at a flow rate as high as 6.0 mL/min for a 2 W electromagnetic actuation power at the resonant frequency of 20 Hz. The actuation frequency-dependent flow rate is in excellent agreement with a damped oscillator model.