Abstract: Response surface methodology was applied to optimize the drug loading rate of persimmon leaf total flavonoids sustained release pellets.On the basis of single factor experiment,the concentration of sodium alginate,the concentration of chitosan,quantity of reagent and reaction temperature were treated as independent variable and drug loading rate was used as a response value.The significance of each factor and their interactions were investigated by response surface methodology.Finally,the optimized preparation technology was ascertained as: the concentration of sodium alginate was 2.75%,the concentration of chitosan was 2.08%,quantity of reagent was 35.94%,reaction temperature was 51 ℃,and drug loading rate was 22.41%.Using response surface methodology to optimize the preparation technology of sustained release pellets from persimmon leaf total flavonoids was feasible.

Key words: persimmon leaf total flavonoids, sustained release pellets, response surface methodology, drug loading rate