This study developed an optimal pre-processing technique for the reference substance of the classic formula Gualou Xiebai Banxia Decoction(GXBD) and established a comprehensive quality control method for GXBD reference substance to provide a reference for its overall quality evaluation. The authors prepared 15 batches of GXBD samples and innovatively used the extracted ion chromatogram under the base peak chromatogram mode to establish a liquid chromatography-mass spectrometry(LC-MS) fingerprint, identify characteristic peaks, and perform quantitative analysis of indicator components. The yield of the 15 batches of GXBD samples ranged from 50.28% to 76.20%. In the positive ion mode, 12 common characteristic peaks were detected in the LC-MS fingerprint, and the structures of five common peaks were identified by comparison with reference standards. The similarity between the fingerprint profiles of different batches of samples and the reference fingerprint profile ranged from 0.920 to 0.984. Finally, liquid chromatography-triple quadrupole mass spectrometry(LC-QQQ/MS) in multiple reaction monitoring(MRM) mode was used to determine the content of eight indicator components in GXBD, including loliolide, chrysoeriol, rutin, cucurbitacin D, macrostemonoside Ⅰ, 25S-timosaponin B Ⅱ, 25R-timosaponin B Ⅱ, and peptide proline-tryptophan-valine-proline-glycine(PWVPG). The method established in this study can reduce matrix interference in the compound, and it has good accuracy, stability, and practical value. It effectively reflects the quality attributes of GXBD samples and can be used for the comprehensive quality control of GXBD.
Keywords: Gualou Xiebai Banxia decoction; LC-MS fingerprint; content determination; quality control.