Trapping of cells by insulator-based dielectrophoresis using open-top microstructures

The ability to manipulate biological cells is a fundamental need of many biological and medical applications. Insulator-based dielectrophoresis (iDEP) trapping involves the use of insulating structures that squeeze the electric field in a conductive solution to create a nonuniform electric field. In this work, a microchip was designed and fabricated for iDEP trapping with open-top microstructures. Microelectrodes were deposited on the substrate and the voltage required was minimized by reducing the distance between them. Human carcinoma (HeLa) cells were trapped under different frequencies to demonstrate the usability of the present microchip. Negative and positive dielectrophoresis (DEP) of cells were observed at low and high frequencies, respectively. The open-top microstructures are suitable for trapping cells and biological samples that can then easily undergo further treatment, such as culturing or contact detection. Since the cover is absent in open-top microstructures, there is no interference in the intensity of the emitted light during fluorescent detection. Furthermore, the Joule heat, which is generated by the application of high voltage in the open-top microstructure, can be dissipated more effectively.