4uL of protein solution is sufficient to fill an entire CrystalCard™ with ca. 800 individual crystallization experiments.  Each aqueous droplet (plug) forms at the mixer where protein, buffer and precipitant combine.  The plugs spontaneously form when coming in contact with the inert, immiscible carrier fluid.

NO CROSS CONTAMINATION!
A thick layer of carrier fluid between the plug and the wall of the microcapillary
prevents any cross-contamination, making each plug a separate and distinct
experiment.