Résumé
Objective: To investigate and optimize the formulation of sophoridine liposomes. Methods: Sophoridine liposomes were prepared by ammonium sulfate transmembrane gradient method. On the basis of single factor experiments, the effects of influence factors, such as entrapment efficiency, drug loading, and comprehensive indexes, were investigated by using central composite design and response surface method. The influence factors included the concentration of drug and ammonium sulfate. The data were imitated using multi-linear equation and second-order polynomial equation. Results: The latter was prior to the former considering from multiple correlation coefficients. Under the optimal conditions, the entrapment efficiency and drug loading of sophoridine liposomes were 51.81% and 5.39%. Conclusion: The optimized preparation technique for sophoridine liposomes is stable and feasible.
Résumé
OBJECTIVE: To draw a comparison between the two preparative technologies of tetrandrine liposomes. METHODS: Tetrandrine liposomes were prepared with ammonium sulfate transmembrane gradient method and film dispersion method respectively. Leaking ratio,particle size,and content of phospholipid of liposomes were selected as the parameters to indicate the stability of liposomes,and the entrapment efficiency was taken as quality index to compare the two preparation technologies. RESULTS: Tetrandrine liposomes prepared with ammonium sulfate transmembrane gradient technology achieved high entrapment efficiency of 81.1% and good stability,while those prepared by film dispersion method had an entrapment efficiency of only 32.9% with poor stability. CONCLUSION: Ammonium sulfate transmembrane gradient method is feasible and superior to the film dispersion method in the preparation of tetrandrine liposome.