Objective:To investigate the bioadhesion and the purgation effect of colon-specific microspheres of total anthraquinones in Rhei Radix et Rhizoma.Method:Observing the percentage of bioadhesive of microspheres in different pH solutions with in vitro perfusion technique and at different intestines part with in vivo perfusion technique to evaluate the bioadhesiveness of colon-specific microspheres of total anthraquinones in Rhei Radix et Rhizoma.With passage of loose stools time

loose stools amount and in 8 h amount of stools as investigation index to investigate the purgation effect of total anthraquinones in Rhei Radix et Rhizoma colon-specific microspheres.Result:The microspheres adhered to the intestines at different pH environment with in vitro perfusion technique.The percentage of bioadhesive was 79%-68% from pH 3.5 to pH 7.0.The microspheres adhered to the stomach

small intestine and colon using in vivo perfusion were 8.5%

23%

63%.The 8 h stools amount of mice lavaging microspheres（0.2 g·kg-1） were（66.4±8.4）pills

the weight of stools in 8 h was（0.74±0.41） g.There was no significant difference between the microspheres and Rhei Radix et Rhizoma（4.0 g·kg-1） on purgation effect.Conclusion:The colon-specific microspheres of total anthraquinones in Rhei Radix et Rhizoma.had correspond purgation effect with equal doses of medicine and the bioadhesive percent was good.