[Monoterpenoids from Paeoniae Radix Rubra based on UPLC-Q-TOF-MS].

The ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry(UPLC-Q-TOF-MS) was used to conduct the qualitative analysis of the monoterpene chemical components from Paeoniae Radix Rubra. Gradient elution was performed on C_(18) HD(2.1 mm×100 mm, 2.5 µm) column with a mobile phase of 0.1% formic acid(A) and acetonitrile(B). The flow rate was 0.4 mL·min~(-1) and the column temperature was 30 ℃. MS analysis was conducted in both positive and negative ionization modes using electrospray ionization(ESI) source. Qualitative Analysis 10.0 was used for data processing. The identification of chemical components was realized by the combination of standard compounds, fragmentation patterns, and mass spectra data reported in the literature. Forty-one monoterpenoids in Paeoniae Radix Rubra extract were identified. Among them, 8 compounds were reported in Paeoniae Radix Rubra for the first time and 1 was presumed to be the new compound 5″-O-methyl-galloylpaeoniflorin or its positional isomer. The method in this study realizes the rapid identification of monoterpenoids from Paeoniae Radix Rubra and provides a material and scientific basis for quality control and further study on the pharmaceutical effect of Paeoniae Radix Rubra.

Combining multidimensional chromatography-mass spectrometry and feature-based molecular networking methods for the systematic characterization of compounds in the supercritical fluid extract of Tripterygium wilfordii Hook F.

Tripterygium wilfordii Hook F from the family Celastraceae is a traditional Chinese medicine (TCM) whose principal chemical constituents are terpenoids, including sesquiterpene alkaloids and diterpenoids, which have unique and diverse structures and remarkable biological activities. In order to advance pharmacological research and guide the preparation of monomer compounds derived from T. wilfordii, a systematic approach to efficiently discover new compounds or their derivatives is needed. Herein, compound separation and identification were performed by offline reversed-phase × supercritical fluid chromatography coupled mass spectrometry (RP × SFC-Q-TOF-MS/MS) and Global Natural Product Social (GNPS) molecular networking. The 2D chromatography system exhibited a high degree of orthogonality and significant peak capacity, and SFC has an advantage during the separation of sesquiterpene alkaloid isomers. Feature-based molecular networking offers the great advantage of quickly detecting and clustering unknown compounds, which greatly assists in intuitively judging the type of compound, and this networking technique has the potential to dramatically accelerate the identification and characterization of compounds from natural sources. A total of 324 compounds were identified and quantitated, including 284 alkaloids, 22 diterpenoids and 18 triterpenoids, which means that there are numerous potential new compounds with novel structures to be further explored. Overall, feature-based molecular networking provides an effective method for discovering and characterizing novel compounds and guides the separation and preparation of targeted natural products.

Chemical profiling of Qingfei Paidu Decoction by triplex off-line two-dimensional liquid chromatography coupled with quadrupole time-of-flight mass spectrometry.

Qingfei Paidu Decoction is a Chinese medicine formula that has been proved effective in the treatment of coronavirus disease 2019. However, the comprehensive separation and characterization of Qingfei Paidu Decoction are of a great challenge due to the diversity of chemical components in a wide range of polarity. In this study, a triplex off-line two-dimensional liquid chromatography coupled with quadrupole time-of-flight mass spectrometry is developed for the analysis of Qingfei Paidu Decoction. One reversed-phase liquid chromatography×hydrophilic interaction liquid chromatography system and two reversed-phase liquid chromatography×reversed phase liquid chromatography systems were constructed to separate polar components and weak-polar components in Qingfei Paidu Decoction, respectively. Benefiting from the good orthogonality of two-dimensional liquid chromatography and high sensitivity of quadrupole time-of-flight MS, chemical components with different polarities and content were discovered. A total of 749 peaks were detected in positive and negative ionization mode and presented as a four-dimensional data plot. Meanwhile, 498 compounds belonging to 14 categories were tentatively identified. These results provide good supplementary to elucidate the material basis of Qingfei Paidu Decoction. The triplex off-line two-dimensional liquid chromatography-quadrupole time-of-flight mass spectrometry strategy can be a powerful and efficient tool for the separation and characterization of chemical substances in traditional Chinese medicine formulas.

A strategy for efficient enrichment of steroidal alkaloids from Fritillaria based on fluorinated reversed-phase stationary phase.

Plant-derived alkaloids are bioactive natural ingredients, but their contents are relatively low in plants. Therefore, the efficient enrichment of alkaloids is a prerequisite for purification and further pharmacological research. In this study, an efficient and simple strategy for enrichment of steroidal alkaloids in Fritillaria was developed for the first time based on the fluorinated reverse-phase stationary phase (FC8HL). Superior selectivity between alkaloids and non-alkaloids was achieved in a non-aqueous system, and a simple solvent system containing low-content additives was applied to elute alkaloids. Key parameters that affected the elution were investigated, including different types of buffer salts and optimized concentrations. The optimized elution system was then applied to selectively enrich alkaloids from five species of Fritillaria. Its practicability was further demonstrated by enrichment of alkaloids from Fritillaria cirrhosa D.Don at a preparative level. This developed method has great potential for other types of hydrophobic alkaloids.

Combination of multi-model statistical analysis and quantitative fingerprinting in quality evaluation of Shuang-huang-lian oral liquid.

A model consisting of quantitative fingerprinting integrated with fundamental statistical analysis was established to carry out quality control analysis of Shuang-huang-lian (SHL) oral liquid. The quantitative fingerprinting approach was developed by systematic investigation of the chromatographic condition and optimization of a gradient using a complex sample analysis software system (CSASS). Five pivotal components from three traditional Chinese medicines of SHL oral liquid were determined at dual wavelengths, including phillyrin, baicalin, chlorogenic acid, neochlorogenic acid and cryptochlorogenic acid. Among them, neochlorogenic acid and cryptochlorogenic acid were quantified by quantitative analysis of multi-components with a single marker (QAMS) method. Further, the developed quantitative fingerprinting approach was validated. Good linearity with correlation coefficients (R2) higher than 0.9999 were achieved for phillyrin, baicalin and chlorogenic acid. Recoveries of the three analytes were between 96% and 108%. Relative standard deviation (RSD) values were below 3% regarding the stability and intra-day and inter-day precision. Besides, the feasibility of the QAMS method was verified by an external standard method (ESM) using 18 batches of SHL oral liquid. Fifty-nine batches of SHL oral liquid from nine manufacturers were then analyzed. Effective distinction was realized based on a linear principal component analysis (linear-PCA) model by the combination of the quantitative data and chromatographic fingerprinting. The linear-PCA model based on quantitative chromatographic fingerprinting exhibited great advantage over conventional similarity analysis to distinguish between different samples. The strategy provided a particularly simple and effective approach for quality evaluation of SHL oral liquid from various manufacturers. Graphical abstract.

Correction to: Combination of multi-model statistical analysis and quantitative fingerprinting in quality evaluation of Shuang-huang-lian oral liquid.

The authors would like to call the reader's attention to the fact that unfortunately there was a mistake in Table 1 of this contribution.

Application of two-dimensional liquid chromatography in the separation of traditional Chinese medicine.

Traditional Chinese medicines have been widely used to prevent and cure diseases for thousands of years. For the purpose of better understanding the extremely complicated traditional Chinese medicines, powerful separation techniques are essential. Two-dimensional liquid chromatography has been proven to be more powerful for the separation of complex traditional Chinese medicines due to its enhanced peak capacity and resolution compared with one-dimensional liquid chromatography. Enormous efforts have been made on the coupling of independent separation mechanisms to improve the resolving power for complex traditional Chinese medicine samples, including the development and introduction of novel stationary phases. This review aims to give an overview on the applications of two-dimensional liquid chromatography in traditional Chinese medicine research since 2008, including comprehensive two-dimensional liquid chromatography, heart-cutting two-dimensional liquid chromatography both in on-line, and off-line mode. Different couplings of separation modes were respectively discussed based on specific studies, with emphasis on the applications of novel stationary phases in the two-dimensional liquid chromatography.

Preparation of glutathione-functionalized zwitterionic silica material for efficient enrichment of sialylated N-glycopeptides.

A glutathione (GSH)-functionalized silica material was prepared using divinyl sulfone activation chemistry (named SiO2-DVS-GSH). The successful synthesis of the SiO2-DVS-GSH material was confirmed by FT-IR, elemental analysis, and zeta potential analysis. The effects of water content, pH value, and salt concentration in the mobile phase on the model compound (uracil, uridine, cytosine, cytidine, guanosine, xanthosine, orotic acid) retention was studied, and a hydrophilic interaction liquid chromatography (HILIC) retention feature together with electrostatic interaction of the SiO2-DVS-GSH material was observed. The prepared stationary phase was further applied for the separation of oligosaccharide. In addition, the SiO2-DVS-GSH material displayed remarkable selectivity and specificity for the sialylated N-glycopeptides' enrichment from bovine fetuin tryptic digests, even at a mass ratio of 1:1000 (w/w) to bovine serum albumin (BSA, non-glycosylated protein), showing superior performance compared to commercial ZIC-HILIC material. Moreover, the SiO2-DVS-GSH material behaved well in the N-glycopeptides' enrichment from human serum, demonstrating its promising potential for glycoproteomics of complex biological samples. Graphical Abstract A glutathione (GSH)-functionalized silica material was prepared using divinyl sulfone activation chemistry, and it shows remarkable selectivity and specificity for the sialylated N-glycopeptides' enrichment.

In-Depth Analysis of Glycoprotein Sialylation in Serum Using a Dual-Functional Material with Superior Hydrophilicity and Switchable Surface Charge.

Sialylation typically occurs at the terminal of glycans, and its aberration often correlates with diseases including neurological diseases and cancer. However, the analysis of glycoprotein sialylation in complex biological samples is still challenging due to their low abundance. Herein, a histidine-bonded silica (HBS) material with a hydrophilic interaction and switchable surface charge was fabricated to enrich sialylated glycopeptides (SGPs) from the digest of proteomics samples. High selectivity toward SGPs was obtained by combining the superior hydrophilicity and switchable-charge characteristics. During the enrichment of sialylated glycopeptides from bovine fetuin digest, seven glycopeptides were detected even at the ratio of 1:5000 with the nonsialylated glycopeptides, demonstrating the high specificity of SGP enrichment by using HBS material. Then, HBS material was further utilized to selectively enrich SGPs from the protein digest of human serum, and 487 glycosites were identified from only 2 µL of human serum; 92.0% of the glycopeptides contained at least one sialic acid, indicating good performance for SGP enrichment by using HBS material. Furthermore, the prepared HBS material also has great potential applications in the analysis of glycoprotein sialylation from other complex biological samples.

Two-dimensional solid-phase extraction strategy for the selective enrichment of aminoglycosides in milk.

An orthogonal two-dimensional solid-phase extraction strategy was established for the selective enrichment of three aminoglycosides including spectinomycin, streptomycin, and dihydrostreptomycin in milk. A reversed-phase liquid chromatography material (C18 ) and a weak cation-exchange material (TGA) were integrated in a single solid-phase extraction cartridge. The feasibility of two-dimensional clean-up procedure that experienced two-step adsorption, two-step rinsing, and two-step elution was systematically investigated. Based on the orthogonality of reversed-phase and weak cation-exchange procedures, the two-dimensional solid-phase extraction strategy could minimize the interference from the hydrophobic matrix existing in traditional reversed-phase solid-phase extraction. In addition, high ionic strength in the extracts could be effectively removed before the second dimension of weak cation-exchange solid-phase extraction. Combined with liquid chromatography and tandem mass spectrometry, the optimized procedure was validated according to the European Union Commission directive 2002/657/EC. A good performance was achieved in terms of linearity, recovery, precision, decision limit, and detection capability in milk. Finally, the optimized two-dimensional clean-up procedure incorporated with liquid chromatography and tandem mass spectrometry was successfully applied to the rapid monitoring of aminoglycoside residues in milk.

Separation analysis of macrolide antibiotics with good performance on a positively charged C18HCE column.

The separation of basic macrolide antibiotics suffers from peak tailing and poor efficiency on traditional silica-based reversed-phase liquid chromatography columns. In this work, a C18HCE column with positively charged surface was applied to the separation of macrolides. Compared with an Acquity BEH C18 column, the C18HCE column exhibited superior performance in the aspect of peak shape and separation efficiency. The screening of mobile phase additives including formic acid, acetic acid and ammonium formate indicated that formic acid was preferable for providing symmetrical peak shapes. Moreover, the influence of formic acid content was investigated. Analysis speed and mass spectrometry compatibility were also taken into account when optimizing the separation conditions for liquid chromatography coupled with tandem mass spectrometry. The developed method was successfully utilized for the determination of macrolide residues in a honey sample. Azithromycin was chosen as the internal standard for the quantitation of spiramycin and tilmicosin, while roxithromycin was used for erythromycin, tylosin, clarithromycin, josamycin and acetylisovaleryltylosin. Good correlation coefficients (r(2) > 0.9938) for all macrolides were obtained. The intra-day and inter-day recoveries were 73.7-134.7% and 80.7-119.7% with relative standard deviations of 2.5-8.0% and 3.9-16.1%, respectively. Outstanding sensitivity with limits of quantitation (S/N ≥ 10) of 0.02-1 µg/kg and limits of detection (S/N ≥ 3) of 0.01-0.5 µg/kg were achieved.

Practical method for the definition of chromatographic peak parameters in preparative liquid chromatography.

A practical method was established for the definition of chromatographic parameters in preparative liquid chromatography. The parameters contained both the peak broadening level under different amounts of sample loading and the concentration distribution of the target compound in the elution. The parameters of the peak broadening level were defined and expressed as a matrix, which consisted of sample loading, the forward broadening and the backward broadening levels. The concentration distribution of the target compound was described by the heat map of the elution profile. The most suitable stationary phase should exhibit the narrower peak broadening and it was best to broaden to both sides to compare to the peak under analytical conditions. Besides, the concentration distribution of the target compounds should be focused on the middle of the elution. The guiding principles were validated by purification of amitriptyline from the mixture of desipramine and amitriptyline. On the selected column, when the content of the impurity desipramine was lower than 0.1%, the recovery of target compound was much higher than the other columns even when the sample loading was as high as 8.03 mg/cm3 . The parameters and methods could be used for the evaluation and selection of stationary phases in preparative chromatography.

N-Glycosylation site analysis of proteins from Saccharomyces cerevisiae by using hydrophilic interaction liquid chromatography-based enrichment, parallel deglycosylation, and mass spectrometry.

N-Glycosylation site analysis of baker's yeast Saccharomyces cerevisiae is of fundamental significance to elucidate the molecular mechanism of human congenital disorders of glycosylation (CDG). Here we present a mass spectrometry (MS)-based workflow for the profiling of N-glycosylated sites in S. cerevisiae proteins. In this workflow, proteolytic glycopeptides were enriched by using a hydrophilic material named Click TE-Cys to improve the glycopeptide selectivity and coverage. To enhance the reliability of the identified results, the enriched glycopeptides were subjected to parallel deglycosylation by using two endoglycosidases (i.e., PNGase F and Endo Hf), respectively, prior to LC-MS/MS analysis. On the basis of the workflow, a total of 135 N-glycosylated sites including 6 known, 93 potential, and 36 novel sites were identified and mapped to 79 proteins. Among the novel-type sites, nine sites from eight proteins, which were simultaneously identified via PNGase F and Endo Hf deglycosylation, are believed to possess high confidence. The established workflow, together with the profile of N-glycosylated sites, will contribute to the improvement of S. cerevisiae model for revealing the pathogenesis of CDG.

Sample preparation for mass spectrometric analysis of human serum N-glycans using hydrophilic interaction chromatography-based solid phase extraction.

Expression levels of N-linked glycans derived from human serum glycoproteins have been shown to change during the progression of many diseases. Generally, N-glycans released from human serum proteins co-exist with endogenous serum peptides, salts, and other contaminants. Effective removal of these contaminants is essential to obtain the glycan profile of human serum proteins. Here, we developed a sample preparation method for mass spectrometry (MS) analysis of N-linked glycans derived from human serum glycoproteins based on a zwitterionic hydrophilic material named Click TE-Cys. The high hydrophilicity of Click TE-Cys, resulting from its unique surface structure and charge distribution, facilitated removal of co-existing salts and endogenous serum peptides. Furthermore, the present enrichment approach was handled in parallel, thus saving time. Using this method, a total of 47 unique N-glycans released from human serum proteins were identified. The intrabatch and interbatch coefficients of variation for the 47 N-linked glycans were 8.57% ± 0.96% and 9.22% ± 1.03%, respectively. These results demonstrate that the present method is suitable for fast purification of N-linked glycans derived from human serum glycoproteins, and has potential for clinical application.

Highly selective separation of aminoglycoside antibiotics on a zwitterionic Click TE-Cys column.

Hydrophilic interaction liquid chromatography has emerged as a valuable alternative approach to ion-pair chromatography for the separation of aminoglycoside antibiotics in recent years. However, the resolution of structurally related aminoglycosides is a great challenge owing to the limited selectivity. In this work, a cysteine-based zwitterionic stationary phase (named Click TE-Cys) was utilized and compared with five commonly used hydrophilic interaction liquid chromatography columns. Click TE-Cys displayed much better selectivity for structurally similar aminoglycosides. The retention behaviors of aminoglycosides were investigated in detail, revealing that low pH (2.7 or 3.0) and high buffer concentration (≥50 mM) were preferable for achieving good peak shape and selectivity. Effective resolution of ten aminoglycosides including spectinomycin, dihydrostreptomycin, streptomycin, gentamicin C1, gentamicin C2/C2a, gentamicin C1a, kanamycin, paromonycin, tobramycin, and neomycin was realized at optimized conditions. Additionally, spectinomycin and its related impurities were successfully resolved. The results indicated the great potential of the Click TE-Cys column in the separation of aminoglycoside mixtures and related impurities.

Elucidation of active components and target mechanism in Jinqiancao granules for the treatment of prostatitis and benign prostatic hyperplasia.

ETHNOPHARMACOLOGICAL RELEVANCE: Prostatitis and benign prostatic hyperplasia (BPH) are inflammations of the prostate gland, which surrounds the urethra in males. Jinqiancao granules are a traditional Chinese medicine used to treat kidney stones and this medicine consists of four herbs: Desmodium styracifolium (Osbeck) Merr., Pyrrosia calvata (Baker) Ching, Plantago asiatica L. and stigma of Zea mays L. AIM OF THE STUDY: We hypothesized that Jinqiancao granules could be a potential therapy for prostatitis and BPH, and this work aimed to elucidate active compounds in Jinqiancao granules and their target mechanisms for the potential treatment of the two diseases. MATERIALS AND METHODS: Jinqiancao granules were commercially available and purchased. Database-driven data mining and networking were utilized to establish a general correlation between Jinqiancao granules and the two diseases above. Ultra-performance liquid chromatography-mass spectrometry was used for compound separation and characterization. The characterized compounds were evaluated on four G-protein coupled receptors (GPCRs: GPR35, muscarinic acetylcholine receptor M3, alpha-1A adrenergic receptor α1A and cannabinoid receptor CB2). A dynamic mass redistribution technique was applied to evaluate compounds on four GPCRs. Nitric acid (NO) inhibition was tested on the macrophage cell line RAW264.7. Molecular docking was conducted on GPR35-active compounds and GPR35 crystal structure. Statistical analysis using GEO datasets was conducted. RESULTS: Seventy compounds were isolated and twelve showed GPCR activity. Three compounds showed potent GPR35 agonistic activity (EC50 < 10 µM) and the GPR35 agonism action of PAL-21 (Scutellarein) was reported for the first time. Docking results revealed that the GPR35-targeting compounds interacted at the key residues for the agonist-initiated activation of GPR35. Five compounds showed weak antagonistic activity on M3, which was confirmed to be a disease target by statistical analysis. Seventeen compounds showed NO inhibitory activity. Several compounds showed multi-target properties. An experiment-based network reflected a pharmacological relationship between Jinqiancao granules and the two diseases. CONCLUSIONS: This study identified active compounds in Jinqiancao granules that have synergistic mechanisms, contributing to anti-inflammatory effects. The findings provide scientific evidence for the potential use of Jinqiancao granules as a treatment for prostatitis and BPH.

N-desmethyldauricine from Menispermum dauricum DC suppresses triple-negative breast cancer growth in 2D and 3D models by downregulating the NF-κB signaling pathway.

Triple negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, for which targeted therapy regimens are lacking. The traditional Chinese medicine Menispermum dauricum DC (M. dauricum) and its compounds have been reported to have antitumor activity against various cancers; however, their anti-TNBC activity is unknown. In this work, dauricine and N-desmethyldauricine from M. dauricum were separated and identified to have anti-TNBC via a multi-component bioactivity and structure-guided method. The cell counting kit 8 assay showed that dauricine and N-desmethyldauricine inhibited the proliferation of four tested TNBC cell lines, with half maximal inhibitory concentration values ranging from 5.01 µM to 13.16 µM. Further research suggested that N-desmethyldauricine induced cell apoptosis, arrested cell cycle progression in the G0/G1 phase, and inhibited cell migration. Western blot analysis revealed that the proapoptotic protein cleaved-poly-ADP-ribose polymerase 1 was upregulated, and the G0/G1 phase-related proteins cyclin-dependent kinase 2 and cyclin D1 and the migration-related protein matrix metallopeptidase 9 were downregulated. Furthermore, N-desmethyldauricine decreased the protein expression of p65, an important subunit of nuclear factor kappa-beta (NF-κB). Moreover, an antiproliferation assay of three-dimensional (3D) tumor spheroids showed that N-desmethyldauricine diminished cell‒cell adhesion and suppressed the growth of TNBC 3D spheroids. Taken together, these findings indicate that N-desmethyldauricine inhibited the proliferation of TNBC cells and decreased the expression of p65 in the NF-κB pathway.

Offline two-dimensional normal-phase × reversed-phase liquid chromatography coupled with high-resolution mass spectrometry for comprehensive analysis of chemical constituents in Euphorbia kansui.

Euphorbia kansui is the dried root of Euphorbia kansui T. N. Liou ex T.P. Wang. Its main chemical components are diterpenoids, triterpenes, and volatile oil. In this study, an offline two-dimensional (2D) normal-phase × reversed-phase liquid chromatography method coupled with quadrupole time-of-flight mass spectrometry was established to comprehensively analyze the chemical constituents in E. kansui. A total of 240 compounds were identified from the E. kansui extract, including 218 diterpenoids (77 known, 141 new), 16 known volatile oils, and six known triterpenes. The relationship between the structural characteristics and tandem mass spectroscopy fragments of diterpenoids was further analyzed. Based on the characteristic fragment ions, 141 new diterpenoids were determined as 118 ingenane diterpenoids and 23 jatrophane diterpenoids. The newly identified diterpenoids may provide lead compounds for drug discovery, improving the medicinal value of E. kansui.

[Investigation of the chemical components of Ciwujia injection using ultra-high performance liquid chromatography-quadrupole-electrostatic field orbitrap high-resolution mass spectrometry].

Ciwujia injection is commonly used to treat cerebrovascular and central nervous system diseases in clinical practice. It can significantly improve blood lipid levels and endothelial cell function in patients with acute cerebral infarction and promote the proliferation of neural stem cells in cerebral ischemic brain tissues. The injection has also been reported to have good curative effects on cerebrovascular diseases, such as hypertension and cerebral infarction. At present, the material basis of Ciwujia injection remains incompletely understood, and only two studies have reported dozens of components, which were determined using high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF MS). Unfortunately, the lack of research on this injection restricts the in-depth study of its therapeutic mechanism.In the present study, a qualitative method based on ultra-high performance liquid chromatography-quadrupole-electrostatic field orbitrap high-resolution mass spectrometry (UHPLC-Q/Orbitrap HRMS) was developed to analyze the chemical components of Ciwujia injection. Separation was performed on a BEH Shield RP18 column (100 mm×2.1 mm, 1.7 µm) using 0.1% formic acid aqueous solution (A) and acetonitrile (B) as the mobile phases, and gradient elution was performed as follows: 0-2 min, 0%B; 2-4 min, 0%B-5%B; 4-15 min, 5%B-20%B; 15-15.1 min, 20%B-90%B; 15.1-17 min, 90%B. The flow rate and column temperature were set to 0.4 mL/min and 30 ℃ respectively. MS1 and MS2 data were acquired in both positive- and negative-ion modes using a mass spectrometer equipped with an HESI source. For data post-processing, a self-built library including component names, molecular formulas, and chemical structures was established by collecting information on the isolated chemical compounds of Acanthopanax senticosus. The chemical components of the injection were identified by comparison with standard compounds or MS2 data in commercial databases or literature based on precise relative molecular mass and fragment ion information. The fragmentation patterns were also considered. For example, the MS2 data of 3-caffeoylquinic acid (chlorogenic acid), 4-caffeoylquinic acid (cryptochlorogenic acid), and 5-caffeoylquinic acid (neochlorogenic acid) were first analyzed. The results indicated that these compounds possessed similar fragmentation behaviors, yielding product ions at m/z 173 and m/z 179 simultaneously. However, the abundance of the product ion at m/z 173 was much higher in 4-caffeoylquinic acid than in 5-caffeoylquinic acid or 3-caffeoylquinic acid, and the fragment signal at m/z 179 was much stronger for 5-caffeoylquinic acid than for 3-caffeoylquinic acid. Four caffeoylquinic acids were identified using a combination of abundance information and retention times. MS2 data in commercial database and literature were also used to identify unknown constituents. For example, compound 88 was successfully identified as possessing a relative molecular mass and neutral losses similar to those of sinapaldehyde using the database, and compound 80 was identified as salvadoraside because its molecular and fragmentation behaviors were consistent with those reported in the literature. A total of 102 constituents, including 62 phenylpropanoids, 23 organic acids, 7 nucleosides, 1 iridoid, and 9 other compounds, were identified. The phenylpropanoids can be further classified as phenylpropionic acids, phenylpropanols, benzenepropanals, coumarins, and lignans. Among the detected compounds, 16 compounds were confirmed using reference compounds and 65 compounds were identified in Ciwujia injection for the first time. This study is the first to report the feasibility of using the UHPLC-Q/Orbitrap HRMS method to quickly and comprehensively analyze the chemical components of Ciwujia injection. The 27 newly discovered phenylpropanoids provide further material basis for the clinical treatment of neurological diseases and new research targets for the in-depth elucidation of the pharmacodynamic mechanism of Ciwujia injection and its related preparations.

Analysis of alkaloids in Gelsemium elegans Benth using an online heart-cutting + comprehensive RPLC×RPLC system tandem mass spectrometry.

Characterization of alkaloids and new compound discovery become increasing challenging for Gelsemium elegans Benth. (G. elegans), due to the lack of an effective separation method. In this study, we developed a new online heart-cutting + comprehensive (HC) RPLC × RPLC system with pH difference, which was coupled to a mass detector to realize the separation and characterization of alkaloids from G. elegans. 18 Gelsemium standards were used to construct the RPLC × RPLC system with pH difference (pH 3 and 11), and good orthogonality (correlation coefficient 0.3) was obtained. A heart-cutting valve was introduced into the traditional online comprehensive RPLC × RPLC system to remove principal components and improve detection of minor components. The online HC RPLC × RPLC system achieved good resolving power (effective peak capacity 687) in condition of optimized practical factors, like the first- and second-dimension flow rates, modulation period and elution gradient et al. Finally, a total of 256 alkaloids were grouped and tentatively identified, among which 156 were unreported, including a new alkaloid type in G. elegans and many dimeric indole alkaloids, which was an important supplement to the study on chemical constituents of G. elegans.