Comparison between two optimized methods in the preparation process of pennyroyal-β-cyclodextrin inclusion compound

AIM To make a rational choice between orthogonal test design and box-behnken design by a comparison between the two methods in the preparation process of pennyroyal-β-cyclodextrin inclusion compound.METHODS β-cyclodextrin inclusion compounds were prepared by saturated water solution method.Independent variables of the experimental design were the feed ratio(w/v ratio) of β-cyclodextrin and pennyroya(X1),the inclusion time(X2) and the inclusion temperature(X3).Pennyroyal-β-cyclodextrin recovery ratio and drug entrapment efficiency were investigated as the index and optimized by respective orthogonal test design and box-behnken design,the comparison of optimized results was expected to be helpful in the reasonable selection of formulation optimization method.RESULTS The optimizational conclusion could be inferred from the two methods.The design optimum conditions of orthogonal test were as follows: the feed ratio(w/v ratio) of β-cyclodextrin and pennyroyal was 6∶ 1,the inclusion time was 3 h and the inclusion temperature was 60 ℃.The optimum conditions of box-behnken design were the feed ratio(w/v ratio) of β-cyclodextrin and pennyroyal was 6∶ 1,the inclusion time was 3.67 h and the inclusion temperature maintained at 50 ℃.Second-order polynomial equations model was used to analyze interaction effects between the multivariate factors via box-behnken design.CONCLUSION The two methods are suitable for optimizing the preparation of inclusion compound and experimentel results are approximate,Orthogonal test design is relatively simple and needs a few experiments.but box-behnken design predominates in the application of design and investigation in non-linearity model.