Effect of microfluidic rectangular microelectrode geometry on bioparticles manipulation in dielectrophoretic application [version 1; peer review: 4 approved with reservations]

Background: Microfluidic cell manipulation techniques have been continually developed and integrated into miniature chips as a so-called lab-on-a-chip (LOC) platform for high-throughput bioassays. Among the various mechanisms of bioparticles manipulation by electrically induced forces, dielectrophoresis (DEP) has been regarded as the most promising technique utilized in microfluidic systems. Into the micro- to nano-scale level of DEP configuration, the common challenges of undesirable side effects such as electrohydrodynamic effects, joule heating, and electrolysis that may occur in the microfluidic system has always been a hurdle which would severely limit the DEP performance. Methods: A numerical simulation study was performed on a versatile capability of a rectangular type of dielectrophoresis microelectrode with different parametric design configuration variables (channel height: 20-50 µm; electrode width 20-100 µm; electrode spacing 5-50 µm). Results: Numerical study results have shown that the ideal dimension range of design configuration for optimum DEP performance have been identified to be 40µm in channel height, 20-40 µm in electrode width and 5-15µm in electrode spacing, further increasing of the dimensions have shown a decrease in DEP performance consequently abridged the bioparticle manipulation. Conclusion: This investigation of the parametric design of the rectangular geometry microelectrode has provided necessary insight to the microelectrode design information and parametric considerations for optimum DEP device fabrication and enhancement.