[Experimental study on high throughput vitrification by micro-droplet spray method].

There is a great demand for blood and stem cells in clinic. It is difficult to achieve high throughput and to increase the cooling rate at the same time during vitrification. In this paper, a micro-droplet spray system with a container collection device was fabricated, and HepG2 cells were sprayed by this system for high-throughput vitrification. First, the container collection device and a cryo-paper were used to receive micro-droplets in the spray vitrification system. The results showed that the cell survival rate and 24h adhesion rate in container collection vitrification group were significantly higher than those in cryo-paper collection group. Second, HepG2 cells were sprayed and vitrified at increased cell density, and it was found that the results of micro-droplet spray vitrification did not change significantly. Finally, micro-droplet spray vitrification is compared with slow freezing. Cell processing capacity in the vitrification group increased, meanwhile, the cell survival rate and 24h adhesion rate in the vitrification group were significantly higher than those in slow freezing group. The results indicated that the micro-droplet spray vitrification system with container collection device designed in this paper can achieve high-throughput cell vitrification, which is of great significance for mass preservation of small cells.