Figure 2.

Microliter CPA droplet printing and vitrification. A) Image of printed droplet next to the printing tip, captured by camera with a high‐speed flashlight. B) The effect of printing pressure and printing tip diameter on the droplet volume (n = 20). Printing time was 5 ms. C) The effect of printing time (i.e., pressure pulse duration) and printing tip diameter on the droplet volume (n = 20). Printing pressure was 8 kPa. D) Image of a crystallized droplet (4 µL) when the droplet was printed directly into LN₂. E) Representative X‐ray diffraction pattern of a crystallized droplet. The dark ring represents the tubing material used to hold the droplet for measurement. F) Levitation time of droplet on the surface of LN₂ increased with increasing droplet volume (n = 10). But for large droplet size (i.e., 32 and 40 µL), droplet sank directly into LN₂. G) Image of a vitrified droplet (4 µL) when the droplet was printed onto a cryogenic copper dish. H) Representative X‐ray diffraction pattern of a vitrified droplet. I) Required PG concentration for vitrification using different droplet sizes and cooling methods (n = 5). In (B,C,F), data points represent mean ± s.d.. Error bars are included, but may not be visible. Scale bars are 1 mm.