1979 Volume 99 Issue 9 Pages 907-913
Gelatin films, as a model of practical dosage form, and gelatin capsules were exposed to ultraviolet ray, and their photostability was examined from the point of water vapor permeability and dissolution properties. The rate of water vapor transmission decreased within the range of film thickness studied, and its reciprocal increased linearly with increasing exposure time. In indomethacin capsules, the water vapor transmission through the capsular wall was not apparently affected by the ultraviolet irradiation. The dissolution time of gelatin films was also affected and delayed by increasing exposure time. It was saturated after 2 hr exposure but did not change by further exposure. These evidences were reflected on the dissolution rate of indomethacin capsules after 8 hr exposure. It was found that the capsules were stable to photoirradiation under the ordinary storage condition.
