[Preparation and properties of sustained-release pellets of glycyrrhizin effective components].

Objective: To prepare the glycyrrhizin pellets by extrusion-spheronization, and optimize the formulation of sustained release pellets of glycyrrhizin effective components coated with mixed Eudragit RS 100 and Eudragit RL 100.

Method: The sustained-release pellets of glycyrrhizin were prepared by Glatt fluid bed technique. The ratio of Eudragit RS 100 to Eudragit RL 100 in the formulation was optimized. The factors that influence the drug release behaviors and their properties were evaluated.

Result: The optimal coat for drug sustained-release was shown at the ratio of Eudragit RS 100 to Eudragit RL 100 of 4:1, the loading weight of copolymers of 5% and the plasticizer concentration of 15%. The curves of cumulative drug release were fit for Peppas and Higuchi equation.

Conclusion: The optimal sustained release of the glycyrrhizin effective component pellets is featured by adjusting the ratio of Eudragit RS 100 to Eudragit RL 100 and the loading weight of copolymers.