Drug release in vivo and efficacy evaluation of a new colon targeted powder of total saponins of Pulsatilla.

Based on the anti-ulcerative colitis (UC) effect of total saponins of Pulsatilla (PTS), a pH dependent colonic targeting particle design powder of PTS was prepared. The core-shell composite particle design powder of PTS was prepared with pH sensitive polymer material Eudragit S100 superfine powder as shell and the drug as core. The release of PTS composite particle design powder was increased in the artificial colon fluid and decreased in the artificial stomach and small intestine fluid. In this paper, the release performance of Pulsatilla saponin D in PTS and the ulcerative colitis model induced by TNBS in rats were used to evaluate the targeting of PTS composite particle design powder in colon. The results showed that the content of Pulsatilla saponin D in colon tissue was significantly higher than that of the original drug group after oral administration of PTS composite particle design powder. The solubility of Pulsatilla saponin D in colon tissue was also higher than that in the stomach and small intestine. The peak time and retention time in vivo were prolonged, and the maximum blood concentration was decreased (Cmax). The effect of colonic targeting powder of PTS (50 mg/kg)on anti-ulcerative colitis induced by TNBS in SD rats was better than the original drug (200 mg/kg). Therefore, it is a great significance to make the PTS into colon targeted preparation for improving bioavailability, efficacy and reducing gastrointestinal stimulation.