Design and fabrication of a microfluidic device for the dielectrophoretic trapping of microparticles using carbon nanofibers

Microparticle manipulation is an important subject to study; it can be used for the separation of complex mixtures, with applications in environmental pollutant analysis or disease detection. Conventional microparticle separation methods are mostly based on size or molecular weight, leading to reduced purity of the obtained sample. Electromechanical interaction of microparticles has been studied for their manipulation since it offers more selective and efficient results than conventional methods. In this work, a microfluidic device was designed, aimed for its future potential application for trapping of exosomes using dielectrophoresis force using a glassy carbon microfiber as the electrode. A computational model of the device was analyzed to demonstrate an increase in the magnitude of the gradient of the squared electric field created between the fiber and its counter-electrode, reaching values up to 1×10¹⁸ V2/m3. Likewise, functional initial prototypes of the designed device were fabricated, which were used in starting experiments to demonstrate dielectrophoretic trapping of microparticles using PS microbeads with positive dielectrophoresis.