To find out important factors controlling crystal growth rate and perfection of protein crystals in microgravity, a microgravity experiment using a Foton-M3 has been conducted in September 2007. Using seed crystals at constant supersaturation, the growth rate was successfully measured ex-situ for the first time to be 0.7-1.5 times larger than the rate under gravity. The result was very surprising because large reduction of growth rate under reduced gravity has been expected. This experiment will be continued as a “NanoStep” project, which will be started on 21st, July 2012.
