OBJECTIVE To ascertain the substance benchmarks of the classic prescription Huangqi Guizhi Wuwu Decoction (HGWD), examine the quantitative value transfer throughout the entire process of HGWD, from herb pieces to decoction, concentrated solution and finally freeze-dried powder, and provide a valuable reference for the preparation method and scientific evaluation of benchmark samples of classic prescriptions containing volatile substances.

METHODS According to the Key information table of Ancient Classic Prescriptions (25 prescriptions) released by China, 15 batches of HGWD were prepared. The multi-index content determination and characteristic chromatogram analysis methods were established, and the characteristic peak attribution and similarity evaluation were carried out. The multi-index contents of HGWD and its freeze-dried powder were investigated and compared, and the quantitative value transfer in the preparation process of decoction-concentrated solution-freeze-dried powder was analyzed. The physical form of the benchmark samples were scientifically and reasonably determined, and the content and transfer rate range of each component in the HGWD benchmark samples were determined, and the HGWD substance benchmarks were established.

RESULTS The contents of cinnamaldehyde and cinnamyl alcohol in HGWD decreased significantly during the concentration and drying process, and the other index components could be transferred more completely between the decoction, concentrated solution and freeze-dried powder. The similarity of the characteristic chromatograms of 15 batches of HGWD benchmark samples were all over 0.9, and 8 characteristic peaks were identified, which were from Paeoniae γadix Alba, Cinnamomi γamulus and Ginger. The paste-forming rate ranged from 8.0% to 11.0%.The content of Astragaloside Ⅳ was 0.04%-0.07% and the transfer rate was 9.0%-18.0%. The content of paeoniflorin was 1.5%-3.0% and the transfer rate was 33.0%-62.0%. The content of cinnamyl alcohol was 0.02%-0.04%, and the transfer rate was 25.0%-47.0%. The content of cinnamic aldehyde was 0.02%-0.05% and the transfer rate was 0.7%-1.5%. The content of cinnamic acid was 0.03%-0.06% and the transfer rate was 17.5%-34.0%. The content of 6-gingerol was 0.04%-0.08% and the transfer rate was 7.0%-14.0%.

CONCLUSION The physical form of the decoction as the HGWD benchmark sample is determined, which provides reference for the scientific selection of the physical form of the benchmark sample of classic prescriptions containing volatile substances. The quality indexes of HGWD substance benchmarks are established, and the quantitative value transfer is analyzed, which provides the basis for the development of the classic prescription compound preparation.