[Characterization and identification of chemical components in traditional Chinese medicine Psoraleae Fructus based on UHPLC-Q-TOF-MS].

This study was designed to comprehensively characterize and identify the chemical components in traditional Chinese medicine Psoraleae Fructus by establishing an ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry(UHPLC-Q-TOF-MS) method in combination with in-house library. The chromatographic separation conditions(stationary phase, column temperature, mobile phase, and elution gradient) and key MS monitoring parameters(capillary voltage, nozzle voltage, and fragmentor) were sequentially optimized via single-factor experiments. A BEH C_(18) column(2.1 mm×100 mm, 1.7 µm) was finally adopted, with the mobile phase consisting of 0.1% formic acid in water(A) and acetonitrile(B) at the flow rate of 0.4 mL·min~(-1) and column temperature of 30 ℃. Auto MS/MS was utilized for data acquisition in both positive and negative ion modes. By comparison with reference compounds, analysis of the MS~2 fragments, in-house library retrieval and literature research, 83 compounds were identified or tentatively characterized from Psoraleae Fructus, including 58 flavonoids, 11 coumarins, 4 terpenoid phenols, and 10 others. Sixteen of them were identified by comparison with reference compounds, and ten compounds may have not been reported from Psoraleae Fructus. This study achieved a rapid qualitative analysis on the chemical components in Psoraleae Fructus, which provided useful reference for elucidating its material basis and promoting the quality control.

A multi-dimensional liquid chromatography/high-resolution mass spectrometry approach combined with computational data processing for the comprehensive characterization of the multicomponents from Cuscuta chinensis.

Challenges encountered in plant metabolites characterization by liquid chromatography/mass spectrometry can arise from the insufficient chromatography separation, the lack of specific database, and low reliability of identification because of the ubiquitous isomerism. Herein, we present an integral approach, by combining comprehensive off-line two-dimensional liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry (2D-LC/IM-QTOF-MS), automatic peak annotation, molecular networking, and collision cross section (CCS) prediction, aimed to improve the resolution and reliability in MS-oriented metabolites characterization. Using the seeds of Cuscuta chinensis as a case, the configuration of an XBridge Amide column of hydrophilic interaction chromatography (HILIC) and a Zorbax SB-Aq column of reversed-phase chromatography (RPC), in an off-line mode, showed the orthogonality of 0.73 and effective peak capacity of 4361. Data-independent high-definition MSE (HDMSE) in the negative mode could enable high-coverage MS2 data acquisition and enhance the ions resolution, while computational peak annotation workflows facilitated by UNIFITM and Global Natural Products Social Molecular Network (GNPS) could efficiently characterize the targeted and untargeted compound analogs. A total of 302 compounds were identified or tentatively characterized, and 109 thereof were unreported. Moreover, CCS prediction (www.allccs.zhulab.cn) provided more possibilities to distinguish 12 pairs of isomers in the lack of reference standards. The 2D-LC/IM-QTOF-MS approach enabled the collection of five dimension of data related to each component (tR by HILIC and RPC, CCS, m/z in MS1 and MS2), and the intelligent metabolites characterization with more reliable MS data. Conclusively, the established integral strategy can be utilized in metabolome analysis to support the quality control of herbal medicines.

An ion mobility-enabled and high-efficiency hybrid scan approach in combination with ultra-high performance liquid chromatography enabling the comprehensive characterization of the multicomponents from Carthamus tinctorius.

Liquid chromatography/mass spectrometry (LC/MS) is extensively applied for the untargeted/targeted analyses of the herbal components, utilizing data-dependent acquisition (DDA) or data-independent acquisition (DIA) to record the fragmentation information useful for the structural elucidation. A new trend recently has emerged by integrating DDA and DIA to render the hybrid scan, which, unfortunately, has rarely been reported. Herein, by using the Vion™ ion-mobility quadrupole time-of-flight mass spectrometer, a hybrid scan strategy (HDMSE-HDDDA) was presented and validated by the untargeted characterization of the multicomponents from Carthamus tinctorius (safflower), in combination with reversed-phase ultra-high performance liquid chromatography (RP-UHPLC). Good chromatographic separation was achieved on an HSS T3 column within 26 min, while HDMSE-MS/MS was used to acquire the collision-induced dissociation MS2 data in the negative mode. Automatic workflows (e.g., data correction, precursors/product ions matching, and peak annotation) were well established on UNIFI™ (incorporating an in-house library recording 261 known compounds) to process the obtained MS2 data. Compared with single DDA or DIA, the hybrid approach of HDMSE-HDDDA better balanced between the coverage and reliability, led to high-definition MS spectra, offered useful collision cross section (CCS) information, and showed satisfactory identification performance comparable to MSE. A total of 141 components (involving 41 quinochalcones, 66 flavanols/flavones, 11 flavanones, 6 organic acids, 1 polyacetylene, and 16 others) were characterized from safflower. Moreover, CCS prediction could assist isomers characterization, to some extent. Conclusively, this hybrid scan approach enables a dimension-enhanced MS data acquisition strategy providing the complementary structural information, which more suits the chemical characterization of complex samples.