Integration of continuous microfluidic electrokinetic bioparticle preconcentration with programmable extraction into...

This study presents a hybrid platform that integrates continuous and digital microfluidics (DMF) to generate preconcentrated discrete droplets from ionic concentration-polarization (ICP) based preconcentration occurring within a continuous medium. This study expands previous work on droplet generation using electrowetting-on-dielectric (EWOD)-based DMF, transitioning from continuous flow in a microchannel to incorporating electrokinetic molecule preconcentration, followed by the extraction of the molecules into droplets in air, without the need for an oil phase, while effectively maintaining their molecular preconcentrated state. Experiments were complemented with numerical simulations and an analytical model, showing qualitative agreement.