Objective: To study in vitro release of Xingnaojing microemulsion and to investigate the release mechanism.
Method: The concentration of jasminoidin was determined by HPLC and the concentration of Aipian was determined by GC. In vitro release characteristics were conducted by dialysis technique. Model fitting was used to determine the kinetics and mechanism.
Result: Jasminoidin released completely within 2 h, fitting the Weibell model best. The release of borneol fitted first order model.
Conclusion: The release mechanisms of different types of medicines are quite different. The different types of medicines dissolve in the different phases in the microemulsion.