Stability of Xuesaitong capsules in gastrointestinal lavage fluid

Abstract

Objective: To obtain a formulation with high bioavailability through evaluation of the stability of three types of Xuesaitong capsules in the stomachs and intestines of rats. We compared the stability of the Panax notoginsenoside R1 as well as the ginsenosides Rg1, Rb1, Re, and Rd in different formulations. Methods: Artificial stomach fluid (ASF) and artificial intestinal fluid (AIF) were prepared. Stability of three types of Xuesaitong capsules was examined for 4 h in stomachs and 24 h in intestines. Samples were analyzed at different times by high-performance liquid chromatography. Percent content of NGR1, GRg1, GRb1, GRe, and GRd at different times was calculated. Results: Hard capsules incubated in ASF disintegrated within 2–3 min, whereas soft capsules disintegrated within 7–8 min. Components in hard capsules were dissolved rapidly in water, with content of each compound reaching 90% in 5 min, and degradation of each compound reaching 30–50% after incubation for 240 min. Dissolution and degradation of each component in soft capsules with a water-soluble base tended to balance at 30–90 min. Contents in soft capsules with a lipid-soluble base showed slow dissolution after ASF incubation for 120 min. Five saponins in identical types of capsules incubated in ASF had similar stability curves. Contents of hard capsules and soft capsules with a water-soluble base degraded rapidly within 30 min and reached a plateau when Xuesaitong capsules were incubated in AIF. Conclusions: Contents of capsules with a lipid-soluble base degraded slower than the other two types of capsules incubated in ASF and AIF, suggesting that they may have better bioavailability.

Keywords

• Xuesaitong capsule
• Panax notoginsenoside
• Gastric lavage fluid
• Stability
• Chinese herbal medicine