Journal of Chromatography B最新文献

Detection of β-2 transferrin in body fluid could help identify cerebrospinal fluid (CSF) leakage. The most common method, isoelectric focusing, was qualitative and could not provide detailed N-glycan structural information. We presented an alternative method using top-down liquid chromatography-time of flight mass spectrometry (LC-TOF MS). After immunoaffinity enrichment, fluid transferrin glycoforms were analyzed by a high-resolution LC-TOF MS, and the N-glycan structure predicted by accurate mass. The performance was validated with imprecision at 15%, with a cut-off of 0.04 for β-2 transferrin to tetrasialotransferrin ratio to confirm the presence of CSF in fluid samples.

A selective and sensitive liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) method was developed and validated for simultaneous quantitation of a cassette of 8 drugs, including docetaxel, erlotinib, loperamide, riluzole, vemurafenib, verapamil, elacridar and tariquidar. Stable isotopically labeled compounds were available for use as internal standards for all compounds, except for tariquidar for which we used elacridar-d4. Sample pre-treatment involved liquid–liquid extraction using tert-butyl-methyl ether as this resulted in good recovery and low ion suppression. Chromatographic separation was achieved using a Zorbax Extend C18 analytical column and a linear gradient from 20 % to 95 % methanol in 0.1 % (v/v) formic acid in water. MS/MS detection using multiple reaction monitoring was done in positive ionization mode. We validated this assay for human and mouse plasma and mouse brain homogenates. The calibration curves were linear over a range 1–200 nM for each drug in the mix, except for tariquidar probably due to the lack of a stable isotope labeled analog. The intra-day and inter-day accuracies were within the 85–115 % range for all compounds at low, medium and high concentrations in the three different matrices. Similarly, the precision for all compounds at three different concentration levels ranged below 15 %, with the exception of tariquidar in mouse plasma and brain homogenate and riluzole in brain homogenate. Pilot studies have confirmed that the method is suitable for the analysis of mouse plasma samples and brain homogenates following cassette dosing of this mixture in mice.

Xiaoyan Tuire Granule is a type of Chinese patent medicine that has been proven effective in treating respiratory tract infections. However, while it has been successfully introduced into clinical use, more knowledge is still needed regarding its chemical components and pharmacokinetics. This study investigated the chemical profile in the medicine and rat plasma by ultra high-performance liquid chromatography coupled with Q Exactive hybrid quadrupole-orbitrap high-resolution accurate mass spectrometry (UHPLC-Orbitrap-MS/MS). Subsequently, it developed a validated ultra high-performance liquid chromatography coupled with quadrupole mass spectrometry (UHPLC-MS/MS) method for determining five components in rat plasma after oral administration of Xiaoyan Tuire Granule. As a result, a total of 106 constituents were inferred, including 9 terpenoids, 29 flavonoids, 33 organic acids, 12 phenylpropanoids and 23 other compounds. After administration, 86 compounds were inferred in rat plasma, including 73 prototypes and 13 metabolites. The metabolic pathways were primarily hydrogenation, glucuronic acid conjugation, sulfate conjugation, hydrolysis and methylation. The established method determined the contents of esculetin, esculin, isovitexin, caffeic acid and p-coumaric acid had a good separation, and all the legal verification met the requirements. The pharmacokinetic results indicate that the absorption rate of the five compounds in vivo was rapid, with a T_max of less than 0.25 h, and the elimination rate was also fast, with a half-time (T_1/2) ranging from 1.22 h to 2.19 h. It is worth noting that esculin and esculetin have similar half-time in vivo due to their structural similarities. Among these five compounds, the AUC_0-∞ and MRT_0-∞ of p-coumaric acid and esculetin were relatively higher, indicating higher exposure and longer residence time of both compounds in vivo. In conclusion, this paper researched the chemical constituents and pharmacokinetics of Xiaoyan Tuire Granule, which provided the reference for further study.

Mycobacteria possess unique and robust lipid profile responsible for their pathogenesis and drug resistance. Mycolic acid (MA) represents an attractive diagnostic biomarker being absent in humans, inert and known to modulate host-pathogen interaction. Accurate measurement of MA is significant to design efficient therapeutics. Despite considerable advances in Liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) based approaches, quantification of mycobacterial lipids including MA is still challenging mainly because of ion suppression effects due to complex matrix and non-availability of suitable internal standards for MA. The current study demonstrates the use of standard addition method (SAM) to circumvent this problem and provides a reliable and exhaustive analytical method to quantify mycobacterial MA based on reversed-phase ultra-high-performance liquid chromatography- mass spectrometry data acquisition. In this method, multiple reaction monitoring (MRM) has been applied, wherein 16 MRM channels or transitions have been chosen for quantification of alpha-, methoxy- and keto-MAs with C-24 and C-26 hydrocarbon chains that are actually best suited for TB diagnostics. We found that the overall methodological limit of detection and limit of quantification were in the range 0.05–0.71 ng/µl and 0.16–2.16 ng/µl. Taken together, SAM quantitative technique could serve as promising alternative for relative concentration determination of MA to aid medical research.

Our manuscript managed to hyphenate the novelty and sustainability in one method. A novel combination of molnupiravir (MNP) and nirmatrelvir (NTV) was found to be a potential symbiotic therapy against SARS-CoV-2. Yet, there is no analytical method published for either determination or stability investigation of this combination simultaneously. So, the proposed HPLC technique focused on determination of MNP and NTV in presence of their degradation products. The sustainability was achieved in our method by using chemometrics tools to quantify NTV in presence of its co-eluted degradation product (NTV-D) without excessive time and solvent usage for separation (run time 5 min.). Moreover, the linearity parameters of both MNP and NTV, including correlation coefficient, LOD and LOQ, have been enhanced significantly after chemometrics treatment through convolution of the resultant derivative curves using trigonometric Fourier function. For example, LOQ of MNP decreased from 3.53 to 0.31 µg/mL and for NTV, LOQ decreased from 4.98 to 2.10 µg/mL after chemometrics treatment. The stability results of the proposed method indicates that no interaction or change in stability behavior of both drugs when co-administered with each other. Thus, this can be used as an empirical basis to initiate clinical trials of this combination for the treatment of COVID-19 patients.

Additionally, in order to determine the impact of chemometric methods in minimizing analysis time and reducing solvent, energy, and waste consumption, our chemometric methodology is evaluated in terms of greenness and blueness (dichromic assessment) using AGREE and BAGI, respectively. Besides, the method sustainability using Hexagon was evaluated.

In cancer development and progression, the Hippo signaling pathway functions. The transcriptional enhanced associate domain (TEAD) stands out as a pivotal transcription factor within this pathway, and the suppression of TEAD represents a promising approach for cancer treatment. The primary aim of the study was to establish an analytical method for the concurrent quantification of a novel TEAD target inhibitor, BPI-460372, and its principal metabolites, BPI-460444 and BPI-460456, in human plasma. The chromatographic separation utilized a XSelect™ HSS C₁₈ column (2.1 × 100 mm, 2.5 µm), while quantification was conducted on a SCIEX API 4000 mass spectrometer. 22 plasma samples were tested via the developed method. The calibration curve for BPI-460372 exhibited linearity from 2 to 2000 ng/mL, while its metabolites BPI-460444 and BPI-460456 had linearity between 1 and 1000 ng/mL (r > 0.99). The precision (RSD) was ≤ 17.1 %, and the accuracy (RE) fell within the range of −17.7 % to 15.0 %, all meeting acceptance criteria. The matrix effect was from 101.0 % to 105.8 %. The extraction recovery of analytes fell within the range of 96.8 % to 104.1 % with an RSD of less than 7.4 %. The developed method was effectively utilized in an advanced solid tumor patient, and the concentration trends of the three analytes in plasma were found to be largely consistent. The established analytical method showed great sensitivity, simplicity, accuracy, and reliability for the rapid and simultaneous analysis of the TEAD target inhibitor BPI-460372, alongside its major metabolites BPI-460444 and BPI-460456 in human plasma. This analytical method provided essential support for future clinical investigations and pharmacokinetic analysis.

Polygonatum cyrtonema Hua and its processed products have demonstrated cardio-protective effects, though the underlying mechanisms remain unclear. In this study, plasma metabolic profiling and pattern recognition were employed to explore the cardio-protective mechanisms of both crude and processed P. cyrtonema in a myocardial ischemia model induced by ligation, using gas chromatography-mass spectrometry. Post-modeling, plasma levels of creatine kinase-MB, lactate dehydrogenase, troponin T, and malondialdehyde were significantly elevated but were notably reduced after treatment. Conversely, plasma levels of glutathione peroxidase and superoxide dismutase, which were significantly decreased post-modeling, were restored following treatment. Hematoxylin-eosin (HE) and Masson staining revealed that both crude and processed P. cyrtonema effectively reduced inflammatory infiltration and fibrosis in cardiac tissue. Metabolic profiling identified 34 differential endogenous metabolites in the treatment groups, with 19 confirmed using standard compounds. The linear correlation coefficients (R2) for these standards ranged from 0.9960 to 0.9996, indicating high accuracy. The method exhibited excellent precision and repeatability, with relative standard deviation (RSD) values below 8.57%. Recovery rates were between 95.02% and 105.15%, and the stability of the standard compounds was confirmed after three freeze–thaw cycles, with RSD values under 4.42%. Both crude and processed P. cyrtonema were found to alleviate myocardial ischemia symptoms by regulating branched-chain amino acid metabolism and energy metabolism. These findings provide a solid foundation for the potential clinical use of this herb and its processed products in treating heart disease.

Fermentation-derived short-chain fatty acids (SCFA)⁴ are potential mediators of the health benefits associated with dietary fiber intake. SCFA affect physiological processes locally in the gut and on distant organs via the systemic circulation. Since SCFA are used as energy source for colonocytes and substrate for the liver metabolism, their concentrations in the systemic circulation are low. Therefore, quantification of systemic SCFA requires sensitive analytical techniques. This article covers the optimization and validation of a gas chromatography-mass spectrometry method to measure systemic SCFA concentrations following derivatization with 2,4-difluoroaniline (DFA)⁵ and extraction in ethyl acetate. Sample preparation was optimized by varying the amount of DFA, coupling agent 1,3-dicyclohexylcarbodiimide, ethyl acetate and sodium bicarbonate, which is used to quench derivatization. In addition, evaporation of the samples using a vacuum concentrator resulted in less contamination, notably of acetate, compared to drying with N₂ gas. The method showed excellent linearity with coefficient of variation (R²) > 0.99 and a good precision (relative standard deviation < 20 %) and accuracy. Finally, systemic concentrations of SCFA in human plasma samples could successfully be determined.

Tobacco (Nicotiana tobacum) and tobacco products are the most critical public health challenges today across the globe. Nicotine is the main chemical composition of tobacco and is associated with withdrawal syndrome. A laboratory animal is commonly employed as a model to investigate nicotine toxicity, drug dependence, reinforcing effects, and the protective effects of samples against nicotine-induced toxicity. The first in-vitro model was developed to prove the protective effect of Babbul (Acacia nilotica Linn.) against nicotine poisoning caused by consumption of tobacco products. The HPTLC method for estimating the protective effect against nicotine poisoning was performed by taking the solvent systems dichloromethane, methanol, and liquid ammonia (25 %)(9:1:0.04v/v/v). This in-vitro approach was done by treating the bark of the Acacia nilotica extract with a standard solution of nicotine, which reduced the concentration of nicotine by 39.12 %. The prescribed HPTLC method can be used successfully to assess Acacia nilotica’s protective impact against nicotine toxicity caused by intake of nicotine containing tobacco products.

Background

The Atractylodes chinensis (DC.) Koidz (A. chinensis) Chinese herb possesses numerous therapeutic properties and is extensively utilized in the pharmaceutical industry. Its quality is closely associated with the harvest periods. However, the optimal quality and harvest periods of A. chinensis remain elusive.

Methods

The bioactive compounds of perennial A. chinensis were detected by ultra-high-performance liquid chromatography coupled with quadrupole Orbitrap mass spectrometry (UHPLC-Q-Orbitrap/MS) metabolomics, and differentially abundant compounds were selected by multivariate statistical analysis. Then, variations in the content of differential compounds in samples harvested at different periods were analyzed, while correlation analysis was carried out on the differential compounds to determine the suitable harvest period for distinct components.

Results

A total of 61 bioactive compounds were detected in all samples, grouped into 9 known classes. The results revealed that the chemical compositions of A. chinensis at different harvest periods were significantly different. The volatile oil content in the four-year-old and five-year-old samples was relatively high, at 31.92 mg/g and 32.42 mg/g, respectively. There were also significant differences in the content of the six active ingredients, for example, the five-year-old sample had the highest content of atractylodin (4.38 mg/g). Indeed, the harvest period was correlated with the abundance of most bioactive compounds. Specifically, quinquennial samples were significantly negatively correlated with the abundance of organic acids and aliphatics while moderately positively correlated with the abundance of other classes of bioactive compounds.

Conclusions

According to the results, the ideal harvest time for atractylenolide Ⅲ was 3 years. Regarding organic acids, the optimal harvest time was around 2–3 years. Taken together, these results offer valuable insights to producers for optimizing the harvest period for A. chinensis.