An in-situ filtering pump for particle-sample filtration based on low-voltage electrokinetic mechanism

Microfluidic preparation is one of important functions in miniaturized diagnosis systems. However, most of existing microfluidic devices require external driving sources which occupies the majority of system size and weight. To address the insufficiency, this work provides an active fluidic pumping and filtration mechanism by travelling-wave electroosmosis (TWEO). Based on superposition of TWEO and induced-chard electroosmosis (ICEO), our numerical simulations show particles are tend to be trapped within surface microelectrodes. As driven by TWEO, thus, particle pumping and particle trapping effect are controllable by the particle size and applied electrical potential. Experimentally, in our implemented devices, 6 μm and 10 μm beads are fully trapped with the applied potential larger than 0.75 V. In addition, 91.9% 1 μm beads flowed thorough as device driven at 0.75 V and 82.3% 1 μm beads trapped on surface electrodes as device drive at 1.50 V. Finally, the HL-60 cancer cells are conducted to demonstrate the potential to handle a real-cell sample for a particle-filtration function in the developed device. The developed device provides a promising on-chip method to achieve the active filtering and pumping function with low-power characteristics for future miniaturized healthcare systems.