The dielectrophoresis microfluidic chip for cell separation: Case study of separation of floating cell and moving cells

Dielectrophoresis technique is one of the useful techniques in cell manipulation, especially for separating cells which has similar morphology but cannot separated by simple centrifugation technique. In this work, dielectrophoresis microfluidic device exploit the cells separation technique in two different cases; floating cells (leukocytes) and moving cells (spermatozoa). In this study leukocytes were chosen for floating cells due to they are nearly immotile and have five subpopulations which have similar electrical properties and external morphology, therefore it is very challenge to see the effect of electrophoresis in the separation. On the other hands, the spermatozoa have been chosen as the moving cell because the spermatozoa are activity motile and have two subpopulation, X and Y spermatozoa. Therefore it is very interested to see the effect of electrophoresis in the separation of subpopulation of both leukocyte and spermatozoa. The device is composed of patterning Indium Tin Oxide (ITO) electrode integrated with microchannel. The separation performance was combined with dielectrophroresis force and on-line flow in microfluidic channel. The crossover frequency was used for optimal of separated conditions. Leukocyte were response significantly at 4 Vp-p potential in frequency range from 200-600 kHz in 56 mS/m conductive medium, while bovine spermatozoa highly response at 4 Vp-1 potential in frequency 1-24 MHz in 10 mS/m conductive medium.