Direct Electrostatic Transportation of Frozen Droplets in Liquid Nitrogen for Single Cryopreserved Cell Processing

This paper reports on a droplet transportation technology in liquid nitrogen for cryopreserved biological cell processing. The technology can directly transport frozen droplets in liquid nitrogen by electrostatic force. Low-frequency voltage is utilized to realize synchronous transportation, and thus positioning control can be easily realized. Transportation characteristics were investigated using frozen droplets of 0.3 M mannitol solution, Fluorinert FC-77, and deionized water in liquid nitrogen. The detailed motion measurement using mannitol solution confirmed that a frozen droplet is positioned at a point where electrostatic field is strongest and that a droplet motion is synchronized with the movement of generated electrostatic field.