Fabrication and characterization of hollow needle array for electrokinetic intracellular delivery of biomolecules

Delivering molecules into a single cell is a key technology for differentiation of cells and analyze cell functions. This study aims to develop a method for massive intracellular delivery of biomolecules in a precise manner using electrokinetic forces. We fabricated an array of hollow needles by MEMS technologies to establish a high-throughput cellular delivery method. Dimensional change of the fabricated needle array was investigated. A method to integrate a needle array, PDMS flow channels, and electrodes was developed. We applied a voltage between electrodes placed inside and outside the needle substrate and observed electrokinetic ejection of fluorescent dyes from the fabricated hollow needle array.