Abstract
Studies pertaining cell chips require a cell positioning technique for the application of cell engineering such as single cell analysis, etc. Dielectrophoresis (DEP) is one of the promising methods to realize simultaneous multi-cell positioning. Previously, several research groups performed DEP-based cell manipulation, for example, cell separation, sorting, and positioning. In this study, we verify cell viability after positioning by DEP. We have fabricated a saw-shaped electrode on a glass chip and demonstrated simultaneous multi-cell positioning wherein cells are arranged between electrodes using the negative DEP principle. We describe the designs of two types of electrodes as well as their electric field simulations. The test chips were fabricated by the standard microelectromechanical system (MEMS) technology, and the experiments were performed for both polystyrene beads and living cells. To investigate the influence of DEP on the cell, the viability of the cells after the positioning was examined using a fluorescent dye. The results of this examination confirmed that no cytotoxicity was observed in the case of negative DEP positioning. Consequently, it was shown that the principle of negative DEP can be applied to achieve cell positioning without having a hazardous effect on living cells.