Electrokinetic Particle Sorting By Shape in a Spiral Microchannel

Shape is an intrinsic marker of cell cycle and also a useful indicator of cell state for disease diagnostics. We present in this talk a continuous-flow electrokinetic sorting of spherical and peanut-shaped particles of similar volumes in an asymmetric double-spiral microchannel. It exploits curvature-induced dielectrophoresis (C-iDEP) to focus particles to a tight stream in the first spiral and subsequently displace them to shape-dependent flow paths in the second spiral. We also develop a numerical model to simulate and understand this shape-based particle sorting in spiral microchannels, which predicts the experimental observation qualitatively.