A MEMS-based spiral channel dielectrophoretic chromatography system for cytometry applications

A Prominent Cell Manipulation Technique in BioMEMS: Dielectrophoresis

BioMEMS, the biological and biomedical applications of micro-electro-mechanical systems (MEMS), has attracted considerable attention in recent years and has found widespread applications in disease detection, advanced diagnosis, therapy, drug delivery, implantable devices, and tissue engineering. One of the most essential and leading goals of the BioMEMS and biosensor technologies is to develop point-of-care (POC) testing systems to perform rapid prognostic or diagnostic tests at a patient site with high accuracy. Manipulation of particles in the analyte of interest is a vital task for POC and biosensor platforms. Dielectrophoresis (DEP), the induced movement of particles in a non-uniform electrical field due to polarization effects, is an accurate, fast, low-cost, and marker-free manipulation technique. It has been indicated as a promising method to characterize, isolate, transport, and trap various particles. The aim of this review is to provide fundamental theory and principles of DEP technique, to explain its importance for the BioMEMS and biosensor fields with detailed references to readers, and to identify and exemplify the application areas in biosensors and POC devices. Finally, the challenges faced in DEP-based systems and the future prospects are discussed.

Continuous separation principles using external microaction forces

During the past decade, methods for the continuous separation of microparticles with microaction forces have rapidly advanced. Various action forces have been used in designs of both microchannel and capillary continuous separation systems, which depend on properties such as conductivity, permittivity, absorptivity, refractive index, magnetic susceptibility, and compressibility. Particle migration velocity has been used to characterize the particles. Biological cells have been the most interesting targets of these continuous separation methods.