Multifunctional 3D Viaduct Microelectrodes for Continuous-Flow Dielectrophoretic Railing and Electroporation of Cells Under Modulated Activation

We demonstrate multifunctional silicon 3D viaduct microelectrodes for continuous-flow cell manipulation by railing and cell transfection under a modulated activation. The microelectrodes serve as tracks along which cells can rail under dielectrophoretic force and hydrodynamic drag. A modulated activation was introduced to achieve railing efficiency up to 80%. Furthermore, cell electroporation is realized through sinewave bursts applied with varying amplitude, duration and interval. Successful transfection is demonstrated by delivering 3 kDa dextran molecules into HEK293 cells with > 60% efficiency. The multifunctional 3D viaduct electrodes show great potential for continuous-flow rapid cell railing and sorting and efficient transfection.