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Zotizalkib (ZTK, TPX‐0131) is a fourth‐generation highly effective inhibitor of wild‐type anaplastic lymphoma kinase (ALK) and ALK‐resistant mutations that can penetrate the central nervous system. It exhibited greater potency compared to all five officially approved ALK inhibitors. The aim of this study was to develop a rapid, accurate, eco‐friendly, and highly sensitive ultra‐high‐performance liquid chromatography‐tandem mass spectrometry (UHPLC‐MS/MS) method for measuring the concentration of ZTK in human liver microsomes (HLMs). The validation aspects of the current UHPLC‐MS/MS methodology in the HLMs were conducted in accordance with the bioanalytical method validation standards specified by the US Food and Drug Administration. ZTK and encorafenib were separated using an Agilent C8 column (Eclipse Plus) and an isocratic mobile phase. The calibration curve for the developed ZTK exhibited a linear relationship within the concentration range of 1–3000 ng/mL. The results from the Analytical Green‐ness Metric Approach program (0.76) suggested that the created method demonstrated a significant degree of environmental sustainability. The in vitro half‐life (t1/2) and intrinsic clearance (Clint) of ZTK were determined to be 15.79 min and 51.35 mL/min/kg, respectively that suggests the ZTK exhibits characteristics similar to those of a medication with a high extraction ratio. These approaches are crucial for the progress of novel pharmaceutical development, especially in improving metabolic stability. [ABSTRACT FROM AUTHOR]

Jiawei Huoxiang Zhengqi Pill (JHZP) is a commonly used Chinese patent medicine for the clinical treatment of headache, dizziness, chest tightness as well as abdominal distension, and pain caused by wind‐cold flu. In this study, a comprehensive strategy combining ultra‐high performance liquid chromatography with diode array detector (UHPLC‐DAD) fingerprinting and multi‐component quantitative analysis was established and validated for quality evaluation of JHZP. A total of 49 characteristic common peaks were selected in a chromatographic fingerprinting study to assess the similarity of 15 batches of JHZP. Furthermore, 109 compounds were identified or preliminarily identified from JHZP by coupling with an advanced hybrid linear ion trap‐Orbitrap mass spectrometer. For quantification, the optimized ultra‐performance liquid chromatography with tandem mass spectrometry (UPLC‐MS/MS) method was employed for the simultaneous determination of 13 target compounds within 12 min. The sensitivity, precision, reproducibility, and accuracy of the method were satisfactory. This validated UPLC‐MS/MS method was successfully applied to analyzing 15 batches of JHZP. The proposed comprehensive strategy combining UHPLC‐DAD fingerprinting and multi‐component UPLC‐MS/MS analysis proved to be highly efficient, accurate, and reliable for the quality evaluation of JHZP, which can be considered as a reference for the overall quality evaluation of other Chinese herbal formulations. [ABSTRACT FROM AUTHOR]

Monitoring the levels of amino acids (AAs) in biological cell cultures provides key information to understand the regulation of cell growth and metabolism. Saccharomyces cerevisiae can naturally excrete AAs, making accurate detection and determination of amino acid levels within the cultivation medium pivotal for gaining insights into this still poorly known process. Given that most AAs lack ultraviolet (UV) chromophores or fluorophores necessary for UV and fluorescence detection, derivatization is commonly utilized to enhance amino acid detectability via UV absorption. Unfortunately, this can lead to drawbacks such as derivative instability, labor intensiveness, and poor reproducibility. Hence, this study aimed to develop an accurate and stable hydrophilic interaction liquid chromatography‐tandem mass spectrometry analytical method for the separation of all 20 AAs within a short 17‐min run time. The method provides satisfactory linearity and sensitivity for all analytes. The method has been validated for intra‐ and inter‐day precision, accuracy, recovery, matrix effect, and stability. It has been successfully applied to quantify 20 AAs in samples of yeast cultivation medium. This endeavor seeks to enhance our comprehension of amino acid profiles in the context of cell growth and metabolism within yeast cultivation media. [ABSTRACT FROM AUTHOR]

Much more attention has been paid to the contamination of Alternaria toxins because of food contamination and the threat to human health. In this study, an ultra‐high‐performance liquid chromatography‐tandem mass spectrometry method was developed for the simultaneous detection of the prototypical alternariol, alternariol monomethylether, and the metabolites 4‐oxhydryl alternariol, and alternariol monomethylether 3‐sulfate ammonium salt of Alternaria toxins. The positive samples were used as matrix samples to optimize the different experimental conditions. 0.01% formic acid solution and acetonitrile were used as the mobile phase, and analytes were scanned in negative electron spray ionization under multiple reaction monitoring, and quantitative determination by isotope internal standard method. Application of this method to samples of human plasma and urine showed the detection of the above analytes. The results showed that the recoveries were from 80.40% to 116.4%, intra‐day accuracy was between 0.6% and 8.0%, and inter‐day accuracy was between 1.1% and 12.1%. The limit of detection of the four analytes ranged from 0.02 to 0.6 µg/L in urine, and 0.02 to 0.5 µg/L in plasma, respectively. Thus, the developed method was rapid and accurate for the simultaneous detection of analytes and provided a theoretical basis for the risk assessment of Alternaria toxins for human exposure. [ABSTRACT FROM AUTHOR]

Traditional Chinese medicine (TCM) has garnered significant scientific interest in healthcare but faces increased regulatory scrutiny due to concerns about uncontrolled usage. This study focuses on characterizing Pogostemon cablin (PC) to mitigate potential misuse and identify chemotype differences. Leveraging untargeted metabolomics, we identified 222 distinctive features effectively differentiating PC from Agastache rugosa (AR), reducing misidentification risks. Pogostone and tilianin emerged as potential markers, leading to a high‐performance liquid chromatography‐diode array detection (HPLC‐DAD) method development for PC and AR discrimination. Evaluation of PC chromatograms revealed notable profile and pogostone level differences among samples, suggesting chemotype associations. Untargeted metabolic profiling identified 78 features with significant differences, highlighting 7,3′,4′‐tri‐O‐methyleriodictyol as a potential discriminatory marker between PC chemotypes. The developed HPLC‐DAD method quantified pogostone and 7,3′,4′‐tri‐O‐methyleriodictyol, effectively discriminating PC chemotypes. This platform differentiates PC and AR and distinguishes chemical types within PC, like pogostone‐type and patchoulol‐type. Applied to local TCM stores, it ensures PC authenticity. This approach addresses TCM control concerns, enhancing understanding and application of herbal medicine by providing insights into PC chemical composition and discrimination. [ABSTRACT FROM AUTHOR]

Glutathione (GSH) is an important antioxidant that is generated and degraded via the GSH cycle. Quantification of the main components in the GSH cycle is necessary to evaluate the process of GSH. In this study, a robust ultra‐performance liquid chromatography‐tandem mass spectrometry method for the simultaneous quantification of 10 components (GSH; γ‐glutamylcysteine; cysteinyl‐glycine; n‐acetylcysteine; homocysteine; cysteine; cystine; methionine; glutamate; pyroglutamic acid) in GSH cycle was developed. The approach was optimized in terms of derivative, chromatographic, and spectrometric conditions as well as sample preparation. The unstable thiol groups of GSH, γ‐glutamylcysteine, cysteinyl‐glycine, n‐acetylcysteine, cysteine, and homocysteine were derivatized by n‐ethylmaleimide. The derivatized and underivatized analytes were separated on an amino column with gradient elution. The method was further validated in terms of selectivity (no interference), linearity (R2 > 0.99), precision (% relative standard deviation [RSD%] range from 0.57 to 10.33), accuracy (% relative error [RE%] range from ‐3.42 to 10.92), stability (RSD% < 5.68, RE% range from ‐2.54 to 4.40), recovery (RSD% range from 1.87 to 7.87) and matrix effect (RSD% < 5.42). The validated method was applied to compare the components in the GSH cycle between normal and oxidative stress cells, which would be helpful in clarifying the effect of oxidative stress on the GSH cycle. [ABSTRACT FROM AUTHOR]

While automated peak detection functionalities are available in commercially accessible software, achieving optimal true positive rates frequently necessitates visual inspection and manual adjustments. In the initial phase of this study, hetero‐variants (glycoforms) of a monoclonal antibody were distinguished using liquid chromatography‐mass spectrometry, revealing discernible peaks at the intact level. To comprehensively identify each peak (hetero‐variant) in the intact‐level analysis, a deep learning approach utilizing convolutional neural networks (CNNs) was employed in the subsequent phase of the study. In the current case study, utilizing conventional software for peak identification, five peaks were detected using a 0.5 threshold, whereas seven peaks were identified using the CNN model. The model exhibited strong performance with a probability area under the curve (AUC) of 0.9949, surpassing that of partial least squares discriminant analysis (PLS‐DA) (probability AUC of 0.8041), and locally weighted regression (LWR) (probability AUC of 0.6885) on the data acquired during experimentation in real‐time. The AUC of the receiver operating characteristic curve also illustrated the superior performance of the CNN over PLS‐DA and LWR. [ABSTRACT FROM AUTHOR]

Topotecan (TPT) is used in the treatment of retinoblastoma, the most common malignant intraocular tumor in children. TPT undergoes pH‐dependent hydrolysis of the lactone ring to the ring‐opened carboxylate form, with the lactone form showing antitumor activity. A selective, and highly sensitive ultra‐high‐performance liquid chromatography‐tandem mass spectrometry method was developed for the determination of both forms of TPT in one mobile phase composition in plasma and vitreous humor matrices. The method showed an excellent linear range of 0.375–120 ng/mL for the lactone. For the carboxylate, the linear range was from 0.75 to 120 ng/mL. The matrix effect and the recovery for the lactone ranged from 98.5% to 106.0% in both matrices, for the carboxylate form, it ranged from 94.9% to 101.2%. The dynamics of the transition between TPT lactone and TPT carboxylate were evaluated at different pH environments. The stability of TPT forms was assessed in plasma and vitreous humor at 8 and 37°C and a very fast conversion of lactone to carboxylate form occurred at 37°C in both matrices. The method developed facilitates the investigation of TPT pharmacodynamics and the release kinetics in the development of the innovative local drug delivery systems. [ABSTRACT FROM AUTHOR]

Mas‐related G protein‐coupled receptor X2 (MrgprX2) is acknowledged as a mast cell‐specific receptor, playing a crucial role in orchestrating anaphylactoid responses through mast cell degranulation. It holds promise as a target for regulating allergic and inflammatory diseases mediated by mast cells. Polygonum cuspidatum (PC) has shown notable anti‐anaphylactoid effects, while its pharmacologically active components remain unclear. In this study, we successfully utilized MrgprX2 high‐expressing cell membrane chromatography (CMC), in conjunction with liquid chromatography‐mass spectrometry (LC‐MS), to identify active anti‐anaphylactoid components in PC. Our study pinpointed polydatin, resveratrol, and emodin‐8‐O‐β‐d‐glucoside as potential anti‐anaphylactoid compounds in PC. Their anti‐anaphylactoid activities were evaluated through β‐aminohexosidase and histamine release assays, demonstrating a concentration‐dependent inhibition for both β‐aminohexosidase and histamine release. This approach, integrating MrgprX2 high‐expression CMC with LC‐MS, proves effective in screening potential anti‐anaphylactoid ingredients in natural herbal medicines. The findings from this study illuminated the anti‐anaphylactoid properties of specific components in PC and provided an efficient method for the drug development of natural products. [ABSTRACT FROM AUTHOR]

In this work, the antioxidant components in persimmon (Diospyros kaki) leaves were separated by offline two‐dimensional liquid chromatography‐electrochemical detection (LC×LC‐ECD) and identified by LC‐tandem mass spectrometry (LC‐MS/MS). A total of 33 antioxidants, mainly proanthocyanidins, and glycosides of kaempferol and quercetin, were identified. The antioxidant assays demonstrated that the fractions collected from the first‐dimension LC (1D‐LC) possessed considerable radical scavenging capabilities, with correlation coefficients of peak area versus radical scavenging capability of 1,1‐diphenyl‐2‐picrylhydrazyl and 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) being 0.9335 and 0.9116, respectively. The fingerprinting showed that 37 peaks were present in all samples. The major antioxidant components of persimmon leaves were the glycosides of kaempferol and quercetin. Finally, fourteen antioxidants were quantitatively assessed. Offline LC×LC provided high peak capacity and separation; ECD enabled specific screening and detection of antioxidant components; and MS/MS provided excellent identification capability. In this study, the combination of the three approaches was utilized to screen for antioxidant components in persimmon leaves, with satisfactory findings. In conclusion, this technique is an effective means for rapid analysis of antioxidant components and quality control of medicinal plants, achieving rapid separation of congeners and facilitating more accurate qualitative and quantitative analyses. [ABSTRACT FROM AUTHOR]

The contents of organic acids (OAs) in tea beverage and their relationship with taste intensity have not been fully understood. In this work, a rapid (10 min for a single run) and sensitive (limits of quantification: 0.0044–0.4486 µg/mL) method was developed and validated for the simultaneous determination of 17 OAs in four types of tea, based on liquid chromatography‐tandem mass spectrometry with multiple reaction monitoring mode. The contents of 17 OAs in 96 tea samples were measured at levels between 0.01 and 11.80 g/kg (dried weight). Quinic acid, citric acid, and malic acid were determined as the major OAs in green, black, and raw pu‐erh teas, while oxalic acid and tartaric acid exhibited the highest contents in ripe pu‐erh tea. Taking the OAs composition as input features, a partial least squares regression model was proposed to predict the sourness intensity of tea beverages. The model achieved a root‐mean‐square error of 0.58 and a coefficient of determination of 0.84 for the testing set. The proposed model provides a theoretical way to evaluate the sensory quality of tea infusion based on its chemical composition. [ABSTRACT FROM AUTHOR]

Folic acid (FA) is easily photodegraded to yield 6‐formylpterin and pterin‐6‐carboxylic acid, which can generate reactive oxygen species and result in the formation of oxidized guanine derivatives such as 8‐hydroxy‐2′‐deoxyguanosine and 8‐hydroxy‐guanosine. In this study, we developed a simple, rapid, and sensitive liquid chromatography‐tandem mass spectrometry strategy for the simultaneous determination of FA photolysis products and oxidized guanine derivatives in plasma samples. Chromatographic separation was performed on a Waters HSS T3 column (2.1 × 100 mm, 5.0 μm) with gradient elution at a flow rate of 0.25 mL/min. Plasma samples were first pretreated with 1% formic acid, followed by protein precipitation with methanol. The developed method showed good linear relationships between 1 and 2000 ng/mL (r2 > 0.99). The intra‐ and inter‐day precisions ranged from 2.6% to 7.5% and from 2.5% to 6.5%, respectively. Recoveries of the analytes were between 75.4% and 112.4% with the relative standard deviation < 9.1%. Finally, the method was applied to quantify FA photolysis products and oxidized guanine derivatives in rats with light and non‐light conditions. [ABSTRACT FROM AUTHOR]

Regorafenib is a small‐molecule tyrosine kinase inhibitor with severe hepatotoxicity. It undergoes metabolism mainly by CYP3A4 to generate active metabolites regorafenib‐N‐oxide (M2) and N‐desmethyl‐regorafenib‐N‐oxide (M5). Wuzhi capsule (WZC) is an herbal preparation derived from Schisandra sphenanthera and is potentially used to prevent regorafenib‐induced hepatotoxicity. This study aims to explore the effect of WZC on the pharmacokinetics of regorafenib in rats. An efficient and sensitive liquid chromatography‐tandem mass spectrometry method was developed to quantitatively determine regorafenib and its main metabolites in rat plasma. The proposed method was applied to the pharmacokinetic study of regorafenib in rats, with or without WZC. Coadministration of regorafenib with WZC resulted in a prolonged mean residence time (MRT) of the parent drug but had no statistically significant difference in other pharmacokinetic parameters. While for the main metabolites of regorafenib, WZC decreased the area under the curve and maximum concentration (Cmax), delayed the time to reach Cmax, and prolonged the MRT of M2 and M5. These results indicate that WZC delayed and inhibited the metabolism of regorafenib to M2 and M5 by suppressing CYP3A4. Our study provides implications for the rational use of the WZC‐regorafenib combination in clinical practice. [ABSTRACT FROM AUTHOR]

This review provides an overview of the latest advancements and applications in multi‐dimensional liquid chromatography coupled with mass spectrometry (mD‐LC‐MS), covering aspects such as inter‐laboratory studies, digestion strategy, trapping column, and multi‐level analysis. The shift from an offline to an online workflow reduces sample processing artifacts, analytical variability, analysis time, and the labor required for data acquisition. Over the past few years, this technique has demonstrated sufficient maturity for application across a diverse range of complex products. Moreover, there is potential for this strategy to evolve into an integrated process analytical technology tool for the real‐time monitoring of monoclonal antibody quality. This review also identifies emerging trends, including its application to new modalities, the possibility of evaluating biological activity within the mD‐LC set‐up, and the consideration of multi‐dimensional capillary electrophoresis as an alternative to mD‐LC. As mD‐LC‐MS continues to evolve and integrate emerging trends, it holds the potential to shape the next generation of analytical tools, offering exciting possibilities for enhanced characterization and monitoring of complex biopharmaceutical products. [ABSTRACT FROM AUTHOR]

German chamomile is one of the most effective herbal elements used in anti‐allergic products and as an antioxidant. Herein, the antioxidant activity of different extract fractions of German chamomile was initially evaluated using an off‐line 2,2‐diphenyl‐1‐picrylhydrazyl spectrophotometric assay. The ethyl acetate extract demonstrated the highest efficacy in scavenging free radicals. Based on this, a rapid screening and separation method using ultra‐high‐performance liquid chromatography combined with the 2,2‐diphenyl‐1‐picrylhydrazyl assay was implemented to identify antioxidants in the ethyl acetate fraction of German chamomile flowers. Ten potential radical scavengers were tentatively screened from German chamomile using a target‐guided isolating approach with off‐line two‐dimensional high‐speed countercurrent chromatography and the structures of the compounds were analyzed and identified. Ultimately, 10 radical scavengers were obtained from the ethyl acetate extract with a purity quotient exceeding 90%. The results demonstrated the effectiveness and reproducibility of this method for isolating potential antioxidants from complex mixtures in a targeted manner. This strategy can be applied to the target‐guided isolation of complex mixtures of natural products with broad K‐values and similar structures. [ABSTRACT FROM AUTHOR]

Sanguisorba officinalis L. possesses detoxifying, analgesic, and hemostatic properties. After charred processing, S. officinalis exhibits significantly enhanced medicinal effects. Currently, most pharmacokinetic studies focus on the chemical constituents of unprocessed S. officinalis. There is limited research on the comparison of chemical constituents before and after processing. This study established a pharmacokinetic method using ultra‐high‐performance liquid chromatography‐tandem mass spectroscopy (UHPLC‐MS/MS) to simultaneously determine the levels of four tannin compounds in rat plasma. In negative ion mode, MS/MS detection was performed using an electrospray ionization source. Chromatographic separation was performed using WATERS ACQUITY HSS T3 column (2.1 × 100 mm, 1.8 µm) with a gradient elution of water and acetonitrile as the mobile phase. The pharmacokinetic results indicate that all four compounds reached peak concentrations within 2 h, demonstrating rapid absorption into the bloodstream within the gastrointestinal tract. Notably, the absorption was generally faster in the charred compound of S. officinalis after processing. These four compounds exhibited slower elimination in rat plasma, while in S. officinalis charcoal, the compounds were eliminated more rapidly. The pharmacokinetic results have revealed the pharmacokinetic characteristics of the four analytes in rat plasma which provides valuable reference information for further investigating the in vivo absorption process of S. officinalis after processing. [ABSTRACT FROM AUTHOR]

Zanthoxylum, as a medicinal and edible herbal medicine, has a long history and complex chemical composition. There are many varieties of Zanthoxylum, and there are differences in composition between varieties. In this study, a rapid classification and identification method for the main components of Zanthoxylum was established using ultra‐high‐performance‐liquid chromatography quadrupole‐orbitrap‐mass spectrometry. The components of Shandong Zanthoxylum bungeanum, Wudu Zanthoxylum bungeanum, and Zanthoxylum schinifolium were identified by studying the characteristic fragmentations and neutral losses of characteristic components. A total of 48 common components and 24 different components were identified and the fragmentation patterns of the main components, such as flavonoids, alkaloids, and organic acids were summarized. These findings provided a reference for the study of pharmacodynamic substance basis and quality control of different varieties of Zanthoxylum. [ABSTRACT FROM AUTHOR]

Understanding and comparing the applicability of electromembrane extraction (EME) and liquid‐phase microextraction (LPME) is crucial for selecting an appropriate microextraction approach. In this work, EME and LPME based on supported liquid membranes were compared using biological samples, including whole blood, urine, saliva, and liver tissue. After optimization, efficient EME and LPME of clozapine from four biological samples were achieved. EME provided higher recovery and faster mass transfer for blood and liver tissue than LPME. These advantages were attributed to the electric field disrupting clozapine binding to interfering substances. For urine and saliva, EME demonstrated similar recoveries while achieving faster mass transfer rates. Finally, efficient EME and LPME were validated and evaluated combined with liquid chromatography‐tandem mass spectrometry (LC‐MS/MS). The coefficient of determination of all methods was greater than 0.999, and all methods showed acceptable reproducibility (≤14%), accuracy (90%–110%), and matrix effect (85%–112%). For liver and blood with high viscosity and complex matrices, EME‐LC‐MS/MS provided better sensitivity than LPME‐LC‐MS/MS. The above results indicated that both EME and LPME could be used to isolate non‐polar basic drugs from different biological samples, although EME demonstrated higher recovery rates for liver tissue and blood. [ABSTRACT FROM AUTHOR]

Although filtration is one of the most common steps in sample preparation for chemical analysis, filter membrane materials can leach contaminants and/or retain some analytes in the filtered solutions. In multiclass, multiresidue analysis of veterinary drugs, it is challenging to find one type of filter membrane that does not retain at least some of the analytes before injection in ultrahigh‐performance liquid chromatography‐tandem mass spectrometry (UHPLC‐MS/MS). In this study, different filter membranes were tested for use in UHPLC‐MS/MS analysis of 183 diverse drugs in bovine muscle, kidney, and liver tissues. Membranes evaluated consisted of polytetrafluoroethylene (PTFE), polyvinylidene difluoride (PVDF), polyethersulfone, nylon, and regenerated cellulose. Drug classes represented among the analytes included β‐agonists, β‐lactams, anthelmintics, macrolides, tetracyclines, sulfonamides, tranquilizers, (fluoro)quinolones, anti‐inflammatories, nitroimidazoles, coccidiostats, phenicols, and others. Although the presence of a matrix helped reduce the binding of analytes on surface active sites, all of the filter types partially retained at least some of the drugs in the final extracts. In testing by flow‐injection analysis, all of the membrane filters were also observed to leach interfering components. Ultimately, filtration was avoided altogether in the final sample preparation approach known as the quick, easy, cheap, effective, rugged, safe, efficient, and robust (QuEChERSER) mega‐method, and ultracentrifugation was chosen as an alternative. [ABSTRACT FROM AUTHOR]

The comprehensive and efficient characterization of components in traditional Chinese medicine is crucial for elucidating its active constituents and uncovering its mechanism. Identifying the compounds of the Bushen Huoxue Prescription (BHP) is difficult because of its complex composition and the large difference in concentration among its compounds. In this study, a hydrophilic interaction liquid chromatography coupled with reversed‐phase LC (HILIC × RPLC) offline 2D‐LC tandem high‐resolution mass spectrometry method was established to analyze the total compounds of the BHP. Database screening and molecular networking were performed to identify the compounds. In contrast to conventional 1D chromatography, 2D chromatography increased peak capacity, enriched trace ingredients, and prevented the masking of high‐abundance compounds. A total of 165 compounds were identified, and 14 potential compounds needed to be further identified. This study provided an effective method for comprehensively analyzing the complex system of traditional Chinese medicine compounds. [ABSTRACT FROM AUTHOR]

Polyethylene glycol (PEG) is one of the most commonly used polymers in drug delivery systems. The investigation of the pharmacokinetic behavior of PEG is important for revealing the toxicity and efficiency of PEG‐related Nano‐drug delivery systems. A high through‐put and selective ultra‐high‐performance liquid chromatography with tandem mass spectrometry (UHPLC‐MS/MS) method coupled with collision‐induced dissociation (CID) in source technique was developed and validated to determine PEG1K polymers in cellular samples in this study. The countless precursor ions of PEG1K are dissociated in the source to generate numerous product ions which have different numbers of subunits. The transition of [M+H]+ precursor ions → product ions at m/z 177.1 (four subunits)→89.1 (two subunits) was selected to determine PEG1K due to its high sensitivity. The UHPLC‐MS/MS method coupled with CID in the source showed good linearity over the range of 0.1–10 μg/mL. Intra‐day and inter‐day accuracies and precisions of the assay were all within ± 12.39%. The assay was successfully applied to a cellular pharmacokinetic study of PEG1K in human breast cancer cells. The cytotoxicity of PEG1K polymers was also studied and the results indicated that the cytotoxicity of PEG1K was not significant in the range of 5–1200 μg/mL. [ABSTRACT FROM AUTHOR]

Epimedium (EM) and Psoraleae Fructus (PF) are a traditional herb combination often used as a fixed form to treat osteoporosis disease in the clinic. However, the intricate interactions of this pair remain unknown. In our study, we undertook a comprehensive examination of their compatibility behaviors. Concurrently, a precise and sensitive quantitation method was successfully developed and validated using liquid chromatography‐tandem mass spectrometry for the determination of 12 components. This method was applied in analyzing herbal extracts and biological samples (both in the portal vein and systemic plasma), which was also used to study the pharmacokinetics of the herb pair. The results indicated that the combination of EM and PF enhanced the dissolution of chemical components from PF in extracts, but it had a negligible influence on the contents of the components from EM. On the contrary, the in vivo exposure of the lowly exposed EM flavonoids significantly increased following the combination of EM and PF, whereas the highly exposed psoralen and isopsoralen were greatly reduced. These interactions might be crucial for the synergy and toxicity reduction of the herbal pair in disease treatment, which pave the way for further exploration into the clinical application and pharmacological mechanisms of EM and PF. [ABSTRACT FROM AUTHOR]

A novel, isocratic, sensitive, stability‐indicating high‐performance liquid chromatography method was developed for the separation and quantification of related substances in nitroxoline (NTL). The chromatographic separation has been achieved on Inertsil ODS‐3 V, (250 × 4.6 mm, 5 μm) at 240 nm using ethylenediamine tetraacetic acid buffer and methanol in the ratio of 60:40 v/v as mobile phase. The performance of the method has been checked as per the International Conference on Harmonization guidelines for specificity, linearity, accuracy, precision, and robustness. Regression analysis showed a correlation coefficient value greater than 0.99 for NTL and its three impurities. The detection limit of impurities was in the range of 0.01% (0.05 μg/mL)–0.22% (1.1 μg/mL) indicating the sensitivity of the newly developed method. The accuracy of the method was established based on the recovery obtained between 94.7% and 104.1% for all the impurities. The percentage relative standard deviation obtained for the repeatability was less than 4.0% at the specification level for all impurities. Forced degradation was performed to establish the stability‐indicating nature of the method and to know about the degradation products, the quality of a drug substance changes with time under the influence of stress conditions. Thus, the proposed method was validated and found to be specific, sensitive, linear, accurate, precise, reproducible, and beneficial for routine usage. [ABSTRACT FROM AUTHOR]

This study introduces a cost‐effective, automated ultra‐high‐performance liquid chromatography–tandem mass spectrometry method for the detection of 14 β‐agonists in pork using a novel solid‐phase microextraction probe composed of polyacrylonitrile and molecularly imprinted polymer. Integrated into an automated extraction device, the probe optimizes extraction prior to analysis while reducing expenses and time compared to traditional solid‐phase extraction procedures. The method validation followed the Chinese National Standard (GB/T 27404‐2008) and examined limits of detection, limits of quantification, matrix effects, linearity, intraday, and interday precision. Average recovery rates ranged from 71.6% to 82.2%, with relative standard deviations less than 15%. Limits of detection and limits of quantification ranged from 0.09 to 0.39 and 0.27 to 0.99 μg/kg, respectively. The new method identified positive samples more accurately than the current National Standard GB/T 31658.22‐2022 and demonstrated its potential for routine assessment and regulatory compliance in the detection of β‐agonists in pork. [ABSTRACT FROM AUTHOR]

Sinomenine is an active ingredient extracted from herb medicine, which has been prescribed to treat rheumatoid arthritis in clinics. The present work was to develop a simple method to simultaneously determine sinomenine and its metabolites desmethyl sinomenine and sinomenine N‐oxide in rat plasma by liquid chromatography tandem mass spectrometry. Precursor‐to‐product transitions for detection were m/z 330.2 > 239.1 for sinomenine, m/z 316.2 > 239.1 for desmethyl‐sinomenine, m/z 346.2 > 314.1 for sinomenine N‐oxide and m/z 286.2 > 153.2 for morphine (internal standard), respectively. During the validation and sample quantification, an excellent linear calibration range was observed for all the analytes with correlation coefficients more than 0.999 (r > 0.99). The extraction recovery was more than 85%. No significant matrix effect and carryover were observed. The precision was less than 6.45%, whereas accuracy ranged from –4.10% to 7.23%. The validated method has been successfully applied to the pharmacokinetic study of sinomenine, desmethyl sinomenine, and sinomenine N‐oxide in rat plasma after oral administration of sinomenine at a single dose of 5 mg/kg. The results suggested that sinomenine was rapidly metabolized into its metabolite desmethyl sinomenine and sinomenine N‐oxide. [ABSTRACT FROM AUTHOR]

Aconite is the processed product of the seed root of Aconitum carmichaelii Debx. Aconite is a commonly used traditional Chinese medicine, which is generally used after processing. Black aconite, light aconite, and salted aconite are three different processed aconite products. They have the effects of restoring yang and saving energy enemy, dispersing cold, and relieving pain. However, clinical aconite poisoning cases have frequently been reported. In our study, we investigated the effects of three different processed aconite products on the changes of metabolites in vivo. A total of 42 rats were randomly divided into seven groups with six rats in each group. After three consecutive days of intragastric administration of 2.7 g/kg of the aconite‐processed product, rat serums were obtained. The rat metabolites were detected using liquid chromatography‐tandem mass spectrometry. The altered metabolites related to aconite‐processed products were discovered by statistical analysis using metaboanalyst software. Our study is the first time to comprehensively evaluate the effects of three different processed aconite products on rat metabolites based on pseudotargeted metabolomics. [ABSTRACT FROM AUTHOR]

The level of vitamin B group in human serum is an important index of human health. Among B vitamins, cyanocobalamin in serum is unstable and its content is extremely low. Rapid and simultaneous detection of multiple B vitamins including cyanocobalamin is a challenge. Herein, we have developed a rapid and stable method that can realize the determination of thiamine, riboflavin, nicotinamide, pantothenic acid, pyridoxic acid, biotin, 5‐methyltetrahydrofolate, and cyanocobalamin simultaneously in 6 min. The method was established based on protein precipitation with methanol and then chromatographic separation was achieved using Waters acquity ultra‐high‐performance liquid chromatography high strength silica T3 column, which was stable and sensitive especially for cyanocobalamin. Limit of quantification, precision, trueness, and matrix effect were validated according to the European Medicines Agency and United States Food and Drug guidelines and Clinical and Laboratory Standards Institute guidelines on bioanalytical method. The limit of quantification for thiamine, riboflavin, nicotinamide, pantothenic acid, pyridoxic acid, biotin, 5‐methyltetrahydrofolate, and cyanocobalamin was 0.4, 0.4, 0.8, 2.0, 0.4, 0.1, 0.4, and 0.04 ng/mL separately, respectively. Intra‐ and interday precisions were 1.1%–12.4% and 2.0%–13.5%, respectively. The relative errors were between 0.3% and 13.3%, and the matrix effects were between 2.6% and 10.4%. [ABSTRACT FROM AUTHOR]

Herein, a magnetic borate‐functionalized MXene composite with multiple boronic affinity sites was fabricated by embedding Fe3O4 nanoparticles with 4‐formylphenylboronic acid functionalized Ti3C2Tx nanosheets and served as sorbent for the simultaneous extraction of catecholamines (CAs) in urine samples. The morphology and structure of the magnetic materials were investigated using scanning microscopy, vibrating sample magnetometer, X‐ray photoelectron spectrometer, and X‐ray diffraction. The introduction of polyethyleneimine can amplify the bonded boronic acid groups, thereby effectively improving the adsorption capacities for CAs based on the multiple interactions of boronic affinity, hydrogen bonding, and metal coordination. The adsorption performance was investigated using the kinetics and isotherms models, and the main parameters that influence the extraction efficiency were optimized. Under the most favorable magnetic solid‐phase extraction condition, a sensitive method for the analysis of CAs in urine samples was developed by combining magnetic solid‐phase extraction conditions with high‐performance liquid chromatography detection. The findings illustrated that the proposed approach possessed a wide linearity range of 0.05–250 ng/mL with an acceptable correlation coefficient (R2 ≥ 0.9984) and detection limits of 0.010–0.015 ng/mL for the target CAs. The research not only provides a notable composite with multiple boronic affinity sites but also offers an effective and feasible measure for the detection of CAs in biological samples. [ABSTRACT FROM AUTHOR]

Lingbao Huxin Dan (LBHX) is an effective prescription for treating various cardiovascular diseases. However, its systematic chemical composition analysis and important marker components remain unclear, which hinders the development of standards or guidelines for quality evaluation. Herein, a high‐resolution and efficient method was established to comprehensively investigate the chemical ingredients and metabolites of LBHX by using gas chromatography‐tandem mass spectrometry and ultra‐high‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry. AutoDock Vina was applied to conduct visual screening for identifying potential active compounds targeting two important sick sinus syndrome‐associated proteins. As a result, 53 volatile compounds, as well as 191 non‐volatile chemical components, including bufadienolides, diterpenoids, bile acids, phenolic acids, and triterpenoid saponins, were unambiguously characterized or tentatively identified. Fifty prototypes and 62 metabolites were identified in the plasma of rats, whilst metabolism reactions included phase I reactions (hydrolysis, oxidation, and hydroxylation) and phase II reactions (glucuronidation and methylation). Eleven compounds with good binding affinity have been observed by docking with key proteins. It is the first systematic study on the pharmacodynamic material basis of LBHX and the result consolidates the foundation for further study regarding the mechanism in treating cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Hemp‐based materials have gained interest as alternative feed ingredients for livestock. However, safety concerns arise regarding the transfer of cannabinoids from the plant to the animals. Addressing these concerns requires the use of methods capable of detecting and quantifying cannabinoids in livestock. In this study, a fast and sensitive method was developed for quantification of cannabinoids and cannabinoid metabolites in cattle plasma using liquid chromatography‐tandem mass spectrometry (LC‐MS/MS). The extraction of cannabinoids from the plasma matrix was achieved by combining the Captiva Enhanced Matrix Removal‐Lipid clean‐up and salting‐out assisted liquid–liquid extraction procedure. The developed method underwent validation using various analytical parameters, and the results demonstrated good accuracy, precision, specificity, and high sensitivity. The method was applied to real plasma samples obtained from cattle fed hemp for 2 weeks, and successfully detected various cannabinoids, including delta‐9‐tetrahydrocannabinol. Furthermore, the study revealed that 7‐carboxy cannabidiol, a metabolite of cannabidiol, was the predominant cannabinoid present in the cattle plasma throughout the feeding period, which could remain detectable for weeks after the hemp feeding had ended. [ABSTRACT FROM AUTHOR]

Glutathione, its biosynthesis intermediates, and other thiol metabolites are of central relevance for the redox homeostasis of cells. Their analysis is critical due to the facile interconversion of redox pairs during sampling, sample preparation, and data acquisition, in particular in the electrospray ionization interface. In this work, we propose a fast‐targeted liquid chromatography‐tandem mass spectrometry method to accurately analyze 14 metabolites from the glutathione pathway. N‐Ethylmaleimide reagent is added with the extraction solvent and instantly stabilizes the thiol‐redox state by derivatization. Liquid chromatographic separation of the analytes was performed on a sub‐2 μm superficially porous hydrophilic interaction liquid chromatography column with sulfobetaine chemistry. Tandem mass spectrometry with triple‐quadrupole mass spectrometry in multiple‐reaction monitoring acquisition mode allowed sensitive detection of the targeted metabolites with limits of quantification in the range of 5–25 nM. Run times of 3 min enable a high throughput analysis of cellular samples. For calibration, a 13C‐labelled cell extract was used as an internal standard. The method was validated and the concentrations of glutathione and its biosynthesis intermediates were determined in HeLa cells. [ABSTRACT FROM AUTHOR]

Our previous studies confirmed the efficacy of gross saponins of Tribulus terrestris L. fruit in treating cerebral ischemia. This study aimed to investigate the related mechanisms in vitro. The lipopolysaccharide‐induced BV2 cells model was constructed and treated with gross saponins at different concentrations to explore its anti‐inflammatory activity. The cell metabolite changes were tracked by liquid chromatography‐mass spectrometry (LC‐MS)‐based metabolomics, and the metabolic biomarkers and related metabolic pathways were analyzed. Molecular biochemistry analysis was further used to verify the relevant inflammatory pathways. The results showed that the saponins reduced nitric oxide release and the secretion of tumor necrosis factor‐alpha, interleukin‐1β, and interleukin‐6 from lipopolysaccharide‐induced BV2 cells. Metabolic perturbations occurred in lipopolysaccharide‐treated BV2 cells, which could be reversed by drug treatment via mainly regulating glycerophospholipid metabolism, tryptophan metabolism, purine metabolism pathways, etc. The western blot analysis demonstrated that saponin could suppress the activation of the inflammatory‐related signaling pathway. The present study explored the in vitro anti‐inflammatory mechanism of gross saponins of Tribulus terrestris L. fruit using an LC‐MS‐based cell metabolomics approach, which confirms the great potential of LC‐MS for drug efficacy evaluation and can be applied in other herbal medicine‐related analyses. [ABSTRACT FROM AUTHOR]

Few studies have examined the relationship between lipid metabolism and kidney stone formation, particularly the role of key lipid regulatory factors in kidney stone formation. We evaluated the effect of the lipid regulatory factor‐peroxisome proliferator‐activated receptor alpha on the formation of renal stones in mice by injecting them with glyoxylate followed by treatment with either a peroxisome proliferator‐activated receptor alpha agonist fenofibrate or an antagonist GW6471 (GW). Liquid chromatography coupled with trapped ion mobility spectrometry‐quadrupole‐time‐of‐flight mass spectrometry‐based lipidomics was used to determine the lipid profile in the mouse kidneys. Histological and biochemical analyses showed that the mice injected with glyoxylate exhibited crystal precipitation and renal dysfunction. Crystallization decreased significantly in the fenofibrate group, whereas it increased significantly in the GW group. A total of 184 lipids, including fatty acyls, glycerolipids, glycerophospholipids, and sphingolipids differed significantly between the mice in the model and control groups. Peroxisome proliferator‐activated receptor alpha activity negatively correlated with glyoxylate‐induced kidney stone formation in mice, which may be related to improved fatty acid oxidation, maintenance of ceramide/complex sphingolipids cycle balance, and alleviation of disorder in phospholipid metabolism. [ABSTRACT FROM AUTHOR]

Qiangxin Lishui Prescription (QLP) has been clinically applied for treating heart failure with remarkable curative effects. A multi‐component pharmacokinetic research is very necessary for determining active substances in it. This study aims to profile the traits and differences in the pharmacokinetics of salvianolic acid B, astragaloside IV, calycosin‐7‐O‐β‐D‐glucoside and kaempferol in QLP between normal and chronic heart failure (CHF) rats by microdialysis combined with ultra‐high‐performance liquid chromatography‐tandem mass spectrometry (UHPLC‐MS/MS). Sensitive, selective, and online microdialysis combined with the UHPLC‐MS/MS method was successfully established and applied to study the pharmacokinetics of QLP. The pathological condition of CHF could lead to the enhancement of systematic exposure and reduction of the metabolic rate of four bioactive components for better bioavailability and therapeutic efficacy. The pharmacokinetic results will provide data support for the clinical application of QLP. [ABSTRACT FROM AUTHOR]

Matrix effects can significantly impede the accuracy, sensitivity, and reliability of separation techniques presenting a formidable challenge to the analytical process. It is crucial to address matrix effects to achieve accurate and precise measurements in complex matrices. The multifaceted nature of matrix effects which can be influenced by factors such as target analyte, sample preparation protocol, composition, and choice of instrument necessitates a pragmatic approach when analyzing complex matrices. This review aims to highlight common challenges associated with matrix effects throughout the entire analytical process with emphasis on gas chromatography‐mass spectrometry, liquid chromatography‐mass spectrometry, and sample preparation techniques. These techniques are susceptible to matrix effects that could lead to ion suppression/enhancement or impact the analyte signal at various stages of the analytical workflow. The assessment, quantification, and mitigation of matrix effects are necessary in developing any analytical method. Strategies can be implemented to reduce or eliminate the matrix effect by changing the type of ionization, improving extraction and clean‐up methods, optimization of chromatography conditions, and corrective calibration methods. While development of an effective strategy to completely mitigate matrix effects remains elusive, an integrated approach that combines sample preparation, analytical extraction, and effective instrumental analysis remains the most promising avenue for identifying and resolving matrix effects. [ABSTRACT FROM AUTHOR]

This article proposes a solvent system screening strategy for compounds with similar UV absorption in complex samples by UV spectrophotometer. There is no need to calculate the partition coefficient value of each compound, only the partition coefficient of the whole sample. The partition coefficient value should be close to 1 in order to obtain as many high‐speed counter‐current chromatography fractions as possible. Then, preparative HPLC was used to purify the high‐speed counter‐current chromatography fractions. Based on the above strategy, seven c‐glycosyl flavonoids and an amino acid were successfully obtained from barley seedlings through high‐speed counter‐current chromatography fractionation with ethyl acetate/n‐butanol/water (8:2:10, v:v:v) system followed by preparative HPLC purification. The research shows that high‐speed counter‐current chromatography could be well developed as a tool for fractionation before purification, and greatly improves the separation efficiency. [ABSTRACT FROM AUTHOR]

Sucrose esters (SEs) are crucial tobacco smoke flavor precursors and play a significant role in tobacco's functionality. Due to their structural complexity, the separation and analysis of SEs in tobacco remain a major challenge, and massive structures of SEs have not yet been fully identified. In this study, the fractions enriched in SEs were obtained from oriental and flue‐cured tobacco through a series of pretreatments, and two types of SEs (Types I and II) were distinguished by liquid chromatography‐tandem mass spectrometry (LC‐MSn) analysis, with Type II SEs newly characterized in tobacco. Five groups of main SEs were further purified using preparative high‐performance LC (HPLC) coupled to an evaporative light scattering detector, and their structures were characterized by nuclear magnetic resonance spectrometry techniques including 1H, 13C, correlation spectroscopy, heteronuclear single quantum correlation, and heteronuclear multiple bond correlation. By combining LC‐MSn and nuclear magnetic resonance spectrometry, the structures of eight SE isomers were finally proposed, of which four were newly identified. These findings further enhance the understanding of the structural diversity of SEs in tobacco, serving as a valuable reference for future research on the elucidation, synthesis, and metabolism of SEs. [ABSTRACT FROM AUTHOR]

After medicinal market research, it was found that the harvest time of Ligustri Lucidi Fructus (LLF) was chaotic in practice. In order to determine the optimal harvest period of LLF to ensure its pharmacological activity, metabolomics analysis of LLF at different harvest times based on ultra‐high‐performance liquid chromatography‐triple quadrupole‐(linear ion trap)‐tandem mass spectrometry was established. In this study, 166 differential metabolites (DMs) in 448 metabolites at different harvest times were screened out based on variable importance in projection value, and among them, 94 DMs with regular trends of change in relative content (59 increased and 35 decreased with the growth period) were chosen to further research. The result of the multivariate statistical analysis showed that November was the optimal harvest period of LLF. Additionally, 10‐hydroxyligustroside, oleoside 11‐methyl ester, and salidroside were screened out to be used as the evaluation indicators of immature LLF, while specnuezhenide, nuezhenoside G13, and neonuezhenide were the evaluation indicators of mature LLF. This study provides fundamental insight for metabolite identification and proposes the best harvest period of LLF to avoid confusion in the medicinal market. [ABSTRACT FROM AUTHOR]

Here, an imine‐linked‐based spherical covalent organic framework (COF) was prepared at room temperature. The as‐synthesized spherical COF served as an adsorbent in dispersive solid‐phase extraction (dSPE), by its virtue of great surface area (1542.68 m2/g), regular distribution of pore size (2.95 nm), and excellent stability. Therefore, a simple and high‐efficiency dispersive solid phase extraction method based on a spherical COF coupled with high‐performance liquid chromatography‐tandem mass spectrometry (HPLC‐MS/MS) was established to determine aryl organophosphate esters in biological samples. This approach displayed favorable linearity in the range of 10.0–1000.0 ng/L (r > 0.9989), a high signal enhancement factor (58.8–181.8 folds) with low limits of detection (0.3–3.3 ng/L). Moreover, it could effectively eliminate complex matrix interference to accurately extract seven aryl organophosphate esters from mouse serum and tissue samples with spiked recoveries of 82.0%–117.4%. The as‐synthesized spherical COF has been successfully applied in sample preparation. The dSPE‐HPLC‐MS/MS method based on a spherical COF has potential application to study the pollutants' metabolism in vivo. [ABSTRACT FROM AUTHOR]

Vestibular schwannoma is the most common benign neoplasm of the cerebellopontine angle. Its first symptoms include hearing loss, tinnitus, and vestibular symptoms, followed by cerebellar and brainstem symptoms, along with palsy of the adjacent cranial nerves. However, the clinical picture has unpredictable dynamics and currently, there are no reliable predictors of tumor behavior. Hence, it is desirable to have a fast routine method for analysis of vestibular schwannoma tissues at the molecular level. The major objective of this study was to verify whether a technique using in‐sample specific protein digestion with trypsin would have the potential to provide a proteomic characterization of these pathological tissues. The achieved results showed that the use of this approach with subsequent liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) analysis of released peptides allowed a fast identification of a considerable number of proteins in two differential parts of vestibular schwannoma tissue as well as in tissues of control healthy samples. Furthermore, mathematical analysis of MS data was able to discriminate between pathological vestibular schwannoma tissues and healthy tissues. Thus, in‐sample protein digestion combined with LC‐MS/MS separation and identification of released specific peptides followed by mathematical analysis appears to have the potential for routine characterization of vestibular schwannomas at the molecular level. Data are available via ProteomeXchange with identifier PXD045261. [ABSTRACT FROM AUTHOR]

Interest has increased in the role of N‐acyl amino acids in a variety of disease states and as potential pharmacotherapies. Recently, N‐oleoyl glycine and N‐oleoyl alanine have shown promise in reducing the rewarding effects of drugs of abuse and alleviating withdrawal signs in rodent models. Previously published methods for the quantitation of these analytes by high‐performance liquid chromatography‐tandem mass spectrometry (HPLC‐MS/MS) in tissue were part of extensive lipidomic panels which may result in limited sensitivity and selectivity and also reported low recovery. Presented is a method for the extraction and HPLC‐MS/MS analysis of N‐oleoyl glycine and N‐oleoyl alanine. The bias and precision of the assay were determined to be within ± 20%. The method was shown to be reliable and robust, with over 90% recovery for the low‐level analytes. Increasing concentrations of N‐oleoyl glycine and N‐oleoyl alanine were quantitated in mouse brain and plasma following exogenous administration. This method was developed to serve to support studies investigating the pharmacokinetics and involvement of N‐oleoyl glycine and N‐oleoyl alanine in drug dependence and other diseases. [ABSTRACT FROM AUTHOR]

Physochlainae Radix (PR) is an essential herbal medicine that has been generally applied for treating cough and asthma. In this study, a comprehensive strategy for quality evaluation of PR from different origins was established by integrating qualitative identification, quantitative analysis, and chemometric methods. A total of 58 chemical components were identified by ultra‐high‐performance liquid chromatography coupled with quadrupole time‐of‐flight tandem mass spectrometry (UHPLC‐Q‐TOF‐MS/MS), and a sensitive and rapid UHPLC‐QqQ‐MS/MS method was established for the simultaneous determination of 12 compounds. In addition, multivariate statistical analysis was applied for discriminant analysis to compare the differences among 30 batches of PR samples. The results showed that the 30 batches of PR collected from four provinces could be clustered into three categories, in which scoparone, protocatechuic acid, tropic acid, and scopolin were important components to distinguish the primary and non‐primary producing areas, as well as superior and inferior products of PR. Chemometric results were consistent and validated each other, and systematically explained the intrinsic quality characteristics of PR. This study first demonstrated that LC‐MS combined with multivariate statistical analysis, provided a comprehensive and effective means for quality evaluation of PR. [ABSTRACT FROM AUTHOR]

A selective and sensitive ultra‐high‐performance liquid chromatography‐tandem mass spectrometry method was developed and validated for the determination of three triterpenoid saponins isolated from Astragalus membranaceus leaf extract. In this article, a method for simultaneous determination of Huangqiyenin A, Huangqiyenin E, and Huangqiyenin K was established for the first time. The method was successfully applied to the pharmacokinetic study of Astragalus membranaceus leaf extract after oral administration. Liquid–liquid extraction was applied to plasma sample preparation. Multiple reaction monitoring mode with an electrospray ion source in positive electrospray ionization was chosen to quantify the analytes. Chromatographic separation was performed on a Waters HSS T3 column, using gradient elution with a mobile phase composed of acetonitrile and 5 mM ammonium acetate/water. The pharmacokinetic results showed that all three compounds had the characteristics of rapid absorption‐slow metabolism trend. The time of maximum plasma concentration of Huangqiyenin A is higher than Huangqiyenin E and Huangqiyenin K. And the maximum plasma concentration of Huangqiyenin A is higher as well. The pharmacokinetic results revealed the pharmacokinetic characteristics of the three analytes in rat plasma, which could provide a helpful reference for the further study of Astragalus membranaceus leaf extract. [ABSTRACT FROM AUTHOR]

In the present work, the herb (Poria cocos (Schw.) Wolf) residue, as an environmentally friendly and renewable biomass source, was converted into novel biochar. Biochar/sodium alginate mixed matrix membrane was fabricated. On this basis, a biochar/sodium alginate mixed matrix membrane‐based in‐syringe solid‐phase extraction was developed combined with ultra‐high performance liquid chromatography‐tandem mass spectrometry to determine nitroimidazoles in water samples. The factors including times of exaction, type, and volume of elution solvent, and sample solution pH were thoroughly optimized. Then the correlation coefficient was 0.9995–0.9997. The limit of detection of four analytes was between 0.006 and 0.014 ng/mL, and the recovery was between 79.02% and 99.1%. Consequently, the established method would provide a new perspective on monitoring nitroimidazoles in water samples. [ABSTRACT FROM AUTHOR]

It has been proved that purine metabolites are implicated in various biological syndromes and disorders. Therefore, the realization of panoramic detection of purine metabolites will be of great significance to the pathogenesis of purine metabolic disorders. In the present study, an ultra‐high performance liquid chromatography with tandem mass spectrometry method was developed for the comprehensive quantification of purine metabolites in rat plasma. The 17 purine metabolites were separated and quantified in the short running time of 15 min. The proposed method was strictly validated by applying SeraSub solution as a matrix and proved to be linear (R2 ≥ 0.9944), accurate (the recoveries of all analytes ranged from 85.3% to 103.0%, with relative standard deviation values ≤ 9.3%), and precise (the intra‐ and inter‐day precisions were less than 10.8% and 12.4%, respectively). The method was then successfully applied to the qualification of the endogenous purine metabolites in acute gouty arthritis rats, as well as colchicine and anthocyanin‐intervened rats. Results showed that uric acid, xanthine, hypoxanthine, and xanthine were considered the key factors of acute gouty arthritis. The established method and measurement of purines in rat plasma might help the investigation of the action mechanisms between purine disorders and related diseases. [ABSTRACT FROM AUTHOR]

Platycodi Radix (PR) is a valuable herb that is widely used in the treatment of chronic obstructive pulmonary disease in clinics. However, the mechanism of action for the treatment of chronic obstructive pulmonary disease remains unclear due to the lack of in vivo studies. Our study established a novel integrated strategy based on ultra‐performance liquid chromatography coupled with time‐of‐flight mass spectrometry, network pharmacology, and molecular docking to systematically analyze the tissue distribution and active compounds of PR in vivo and the therapeutic mechanism of chronic obstructive pulmonary disease. First, tissue distribution studies have shown that the lung is the organ with the highest distribution of PR compounds. Subsequently, network pharmacology results showed that the tumor necrosis factor signaling pathway, interleukin‐17 signaling pathway, and mitogen‐activated protein kinase signaling pathway were the critical mechanisms of PR against chronic obstructive pulmonary disease. Ultimately, molecular docking results showed that the key targets were stably bound to the corresponding active compounds of PR. Our study is of great significance for the screening of the key effective compounds and the study of the mechanism of action in traditional Chinese medicine and provides data to support the further development and utilization of PR. [ABSTRACT FROM AUTHOR]

Pharmaceutical development currently relies on quality separation methods from early discovery through to line‐of‐site manufacturing. There have been significant advancements made regarding the column particle packing, internal diameter, length connectivity, the understanding of the impact key parameters like void volume, flow rate, and temperature all that affects the resultant separation quality, that is, resolution, peak shape, peak width, run time, and signal‐to‐noise ratio. There is however a strong need to establish better alternatives to large bulky high‐performance liquid chromatography racks either for process analytical reaction monitoring or mass spectrometry analysis in establishing product quality. Compact, portable high‐pressure liquid chromatography can be a more efficient alternative to traditional ultra‐high pressure liquid chromatography and traditional liquid chromatography. The compact versatile instrument evaluated here allows good separation control with either the on‐board column with fixed ultra‐violet wavelength cartridge or for use with a high‐resolution mass spectrometry. Significant space reduction results in greener lab spaces with improved energy efficiency for smaller labs with lower energy demands. In addition, this compact liquid chromatography was used as a portable reaction monitoring solution to compare forced degradation kinetics and assess portable liquid chromatography‐mass spectrometry capability for the analyses required for pharmaceutical drug product testing. [ABSTRACT FROM AUTHOR]

A sensitive and accurate analytical method was developed and validated to detect bambermycin, a commonly used antibiotic in animal feed and livestock. The presence of bambermycin residues in food products can pose health risks to consumers, emphasizing the need for a sensitive and accurate analytical method. A reversed‐phase analytical column was utilized with a mobile phase comprising 0.005 mol/L ammonium acetate in 5% acetonitrile (A) and 0.005 mol/L ammonium acetate in 95% acetonitrile (B) to achieve effective chromatographic separation. Quantitative determination of bambermycin in various samples, including beef, pork, chicken, milk, eggs, flatfish, eel, and shrimp, was performed using ultra‐high‐performance liquid chromatography‐tandem mass spectrometry. Sample extraction involved a mixture of methanol and a 25% ammonium hydroxide solution, followed by low‐temperature purification and phospholipid removal utilizing a Phree cartridge. The method exhibited a satisfactory recovery rate ranging from 69% to 100%. Validation results demonstrated the reliability, robustness, and accuracy of the method, exhibiting good linearity, precision, and recovery. This validated method can be applied for routine analysis of bambermycin residues, assisting in the development of effective monitoring and control measures to ensure the safety of livestock and aquatic products. [ABSTRACT FROM AUTHOR]

Imidazoquinoline gallamide is a toll‐like receptor 7/8 agonist, belongs to the imidazoquinoline class, has the potential to activate antigen‐presenting cells, and enhances immune response, primarily Th1 response. The COVAXIN is a whole virion inactivated Coronavirus disease 2019 vaccine formulated with this novel adjuvant called, aluminum hydroxide gel Imidazoquinoline gallamide, wherein, Imidazoquinoline gallamide is chemisorbed onto aluminum hydroxide gel. Herein, an analytical method based on liquid chromatography‐tandem mass spectrometry was developed to identify and quantify Imidazoquinoline gallamide in aluminum hydroxide gel Imidazoquinoline gallamide and COVAXIN. The multiple reaction monitoring transitions were optimized for Imidazoquinoline gallamide quantification are [M+H]+ ions with 512.24→343.19 m/z (quantifier ion) and 512.24→360.22 m/z (qualifier ion). The developed method was validated as per the international conference on harmonization quality2 revison1 guidelines. The method was linear in the range of 0.025–10 µg/mL with a coefficient of determination of 0.9985 and the limit of quantification is 0.025 µg/mL. The accuracy was in the range of 82–121 % and intra‐ and inter‐day precision was less than 7.1% and 5.39%, respectively. The expanded uncertainty results are 9.2% for Imidazoquinoline gallamide in the sample. The validated method was successfully applied to evaluate Imidazoquinoline gallamide concentration in every batch of COVAXIN. [ABSTRACT FROM AUTHOR]

To address sustainability issues, the green synthesis of nanomaterials has recently received considerable attention. This article addresses a novel and cost‐effective adsorbent for the extraction of eight phenyl‐N‐methylcarbamate insecticides from water samples. We first synthesized a magnetite/hydroxyapatite nanocomposite using snail shell powder via an environmental friendly approach. The morphology and physicochemical properties of magnetic hydroxyapatite were characterized by Fourier transform infrared spectroscopy, energy‐dispersive X‐ray spectroscopy, and scanning electron microscopy. Magnetic extraction parameters were optimized using a Doehlert matrix. Under optimum conditions, the magnetic extraction coupled with a LC–MS method shows good linearity with R2 ≥ 0.9982, suitable intra‐ and interday precision, and limits of detection and quantification in the range of 0.052–0.093 μg/L and 0.11–0.31 μg/L, respectively. Satisfactory relative recoveries of all carbamates were achieved from fortified water samples in the range of 93.89–101.01%. [ABSTRACT FROM AUTHOR]