[Research of classical prescription based on QbD concept:optimization of extraction process for modified Siwu Decoction].

As an advanced concept in international pharmaceutical research,quality by design( QbD) can fulfill the strategic requirements of drug quality from testing to design. In this paper,the extraction process of Yanggong Prescription which was the modified Siwu Decoction was optimized based on QbD concept. With the extraction amount of solid matter,the content of ferulic acid and the content of paeoniflorin as critical quality attributes( CQAs),the failure mode and effect analysis( FMEA) was used to screen potential critical process parameters( p CPPs). The mathematical model was established by Box-Behnken experimental design to investigate the interaction between critical process parameters( CPPs) and CQAs. Then the design space for the extraction process of Yanggong Prescription was further established and optimized. Analysis of variance showed that the variance of all models was significant( P<0. 01),and the lack-of-fit value was not significant,indicating that the model was statistically significant. The relationship between various factors and the response values could be functionalized by the established models. Finally,through the optimization of the design space,the optimum extraction process of Yanggong Prescription was obtained as follows: 3 extraction times,122 minutes extraction,and 7 times of water adding. The extraction process of Yanggong Prescription based on the QbD concept was robust and reliable,which would provide guidance for the process development and quality control of its formulations.