Systematic analysis of the metabolites of Roukou Wuwei pills by ultra-high-performance liquid chromatography with quadrupole time-of-flight mass spectrometry after oral administration to rats

Roukou Wuwei pill is one of the most commonly used Mongolian medicinal prescriptions and historically used for the treatment of depression. This research aimed to illustrate the metabolic characteristic of Roukou Wuwei pills in vivo. To address this objective, an ultra-high-performance liquid chromatography with quadrupole time-of-flight mass spectrometry method based metabonomics approach was used to detect and analyze the metabolites of Roukou Wuwei pills. The chromatographic separation was completed on an Agilent SB-C₁₈ column (1.8 µm, 2.1 × 50 mm) with a gradient elution system (acetonitrile and 0.1% formic acid-water). Electrospray ionization was operated in a full-scan mode at m/z 100-1000. The data were collected in positive and negative ion modes. The Masslynx 4.1 and SIMCA-P 13.0 software were used to analyze the mass spectrometry data and select the potential metabolites by using an orthogonal partial least-squares discriminant analysis, which was applied to investigate the differences between the blank and drug groups in biosamples of rats. Finally, totally 87 metabolites were detected based on their tandem mass spectrometry data. Among them, 69 metabolites are potential new compounds.