1994 Volume 42 Issue 9 Pages 1948-1950
The crystallinity and disorder parameters of intact and ground ursodeoxycholic acid were determined by the X-ray diffraction method based on Ruland's theor. An increase in grinding time caused a decrease in crystallinity, while the disorder parameters were independent of the grinding time. Dissolution rates were measured for ursodeoxycholic acid with different crystallinities, and the recrystallization behavior of the amorphous samples was investigated during storage in a vapor of water, n-hexane, n-octane and n-decane. The amorphous ursodeoxycholic acid showed enhanced dissolution in ethanol, and was stable only under dry conditions.
