Application of pseudotargeted method combined with multivariate statistical analysis for the quality assessment of traditional Chinese medicine preparation, Sanhuang Tablet as a case.

The quality control of traditional Chinese herbal medicine (TCHM) is considered to be one of the constraints for its modernization and globalization, especially for traditional Chinese medicine preparation (TCMP). The active compounds at high concentration in TCMP are usually selected as markers for qualification and quantification analyses, but we thought these compounds are insufficient to represent the quality of TCMP. For the in-depth investigation, a pseudotargeted analysis method using ultra-high-performance liquid chromatography-quadrupole-orbitrap mass spectrometry operated in the parallel reaction monitoring mode with time-staggered ion list (tsPRM) was proposed to recognize the chemical composition of TCMP. The full scan-based untargeted analysis was carried out to obtain the target ions. After data preprocessing, the target ions were extracted and to be used as inclusion lists for subsequent parallel reaction monitoring (PRM) analysis. The established pseudotargeted method exhibited good repeatability and wide linear range. Moreover, the number of scan points for the ions in the high coelution zone was greatly increased with the help of tsPRM mode, which makes the compound quantification accuracy. Then, the established method was successfully applied to discover analytical markers for Sanhuang Tablet, which demonstrates its applicability and great potential in quality assessment of TCMP. Graphical abstract.