OBJECTIVE To establish physical and chemical fingerprints of Huagan Decoction (HGD) reference samples, determine the content of two index components, and optimize the extraction process for HGD.

METHODS Fifteen batches of HGD reference sample extracts were prepared according to Key Information Table of Ancient Classical Prescriptions. The chemical fingerprint was established by HPLC and the fingerprint similarity was evaluated. The contents of hesperidin and geniposide were determined and the transfer rate was calculated. The physical fingerprint was established and the similarity was analyzed by six physical parameters: paste rate, refractive index, density, conductivity, pH value and surface tension. The quality standard of HGD reference sample was established by physical-chemical fingerprint similarity, physical parameters and index component transfer rate limit. The comprehensive scoring system was established by AHP-CRITIC mixed weighting method, and the optimal extraction process of HGD was screened.

RESULTS The similarity of physical and chemical fingerprints of 15 batches of HGD reference samples was greater than 0.90. The quality standard was established based on the transfer rate of index components, 70%-130% of the mean surface tension, the extraction rate, refractive index, density, conductivity, 90%-110% of the mean pH and the similarity of physical-chemical fingerprint. A comprehensive scoring system was established based on hesperidin transfer rate, geniposide transfer rate, extract rate and conductivity. According to the quality standard and comprehensive score, the optimal extraction process of HGD compound preparation was determined: 10 times the amount of decoction pieces per day, 6 times the amount of water, extracted once, and the extraction time was 80 minutes.

CONCLUSION The quality standard of HGD reference sample based on chemical composition and physical properties can effectively characterize its quality. The optimal extraction process of compound preparation is stable and reliable, which provides a reference for the quality consistency evaluation of the extraction process from HGD reference sample to compound preparation.