Synergistic effects of dielectrophoretic and magnetophoretic forces on continuous cell separation via pinched flow fractionation

The challenges of constraints and imprecision in chemical analysis and medical diagnosis are particularly evident in the separation of blood cells. Pinched flow fractionation, a passive microfluidic technique, has gained attention for its potential in size-based cell separation. Enhancing its efficiency is crucial, especially through integration with external forces or active methods. This study explores the use of dielectrophoresis (DEP) and magnetophoresis (MP) forces to separate platelet cells, red blood cells, white blood cells, and circulating tumor cells. These forces were analyzed both independently and simultaneously. To achieve optimal separation, the Navier–Stokes equations, Newton's second law, and the system's electric and magnetic fields were modeled. Experiments were conducted in a branched microchannel to assess the impact of various parameters, including buffer flow rate, pinched section width, applied voltage, electric field frequency, and magnetic field intensity. The analysis revealed optimal separation efficiency of approximately 99% under the conditions of Wp=20 μm, Q2=1250 μl/h, f=100 kHz, V=3 V, and M=1.5 T. The findings demonstrate that while DEP and MP forces individually enhance separation, their simultaneous application significantly improves precision, achieving complete separation. This optimized system holds great promise for applications in analytical chemistry and medical diagnostics, particularly in blood cell analysis.