Objective: To study the characteristics of intestinal absorption of psoralen and isopsoralen of Xianlinggubao capsule, and compare the absorption of Xianlinggubao capsule prepared by different technologies.
Method: Non everted gut sac method was applied to investigate the influence of absorption sites and drug concentration on psoralen and isopsoralen absorption, which were determined by HPLC.
Result: Although the absorption rate constants of psoralen and isopsoralen in duodenum were more than that in jejunum and ileum, there was no significance difference between them. The absorption rate constants of psoralen kept at the same level when the concentrations of drug solution were at middle and low level, while the absorption rate constant at high level was absolutely lower than them (P < 0.05). The results of isopsoralen were the same as psoralen's.
Conclusion: Intestinal absorption of psoralen and isopsoralen may be affected by the dissolution. The absorption rate constants of psoralen and isopsoralen in new Xianlinggubao capsules are higher. The absorptions of active components absorption has significant difference in different preparation processes of Xianlinggubao capsule.