Ultra-high Performance Liquid Chromatography-tandem Research Articles

Targeted ultra-high performance liquid chromatography-tandem mass spectrometry assay for the quantification of medium-chain phosphatidylcholines in platelets of coronary artery disease patients

In a recent untargeted clinical lipidomics study of platelets of coronary artery disease (CAD) patients, medium-chain phosphatidylcholines (MCPCs) with C8 and C10 fatty acyl residues were found significantly upregulated in the patient group with acute coronary syndrome (ACS) as compared to chronic coronary syndrome (CCS) and healthy controls. To support this finding, this work presents the development and optimization of a targeted UHPLC-QTrap-MS/MS method with multiple reaction monitoring acquisition for the quantitative analysis of MCPCs (PC 10:0/8:0, PC 16:0/8:0, PC 10:0/20:4 and PC 10:0/10:0) in platelets for biomarker validation. A systematic optimization of chromatographic and mass spectrometric parameters was performed. A charged surface hybrid CSH C18 (1.7 µm, 130 Å) column and fine-tuned gradient elution with 2-propanol/acetonitrile and ammonium acetate as additive to the mobile phase was employed in the final method in ESI negative mode. Four selected PC standards (PC 6:0/6:0, PC 8:0/8:0, PC 10:0/10:0 and PC 12:0/12:0), which cover well the carbon and retention rime range of the target analytes, were used for the optimization process and calibration. Quantification was based on matrix-matched calibration with these four selected commercially available MCPC standards as surrogate calibrants and PC 6:0/6:0 (d22) as internal standard. Furthermore, an organic solvent and fatty acyl carbon number-corrected response factor approach gave also accuracies within acceptance limits of bioanalytical validation guidelines and has more generic applicability. Compared to the previous untargeted RPLC-ESI-QTOF-MS/MS method, the optimized targeted UHPLC-QTrap-MS/MS assay showed increased sensitivity and selectivity for the detection of medium-chain PCs in platelet samples of CAD (LOQs in the range of 0.5-5 nmol/L). The method performance parameters indicated its suitability for a future biomarker validation study of MCPCs in platelets.

Determination of seven phenoxy carboxylic acid herbicides in water using dispersive solid phase extraction coupled with ultra-high performance liquid chromatography-tandem mass spectrometry based on metal-organic framework composite aerogel

Phenoxy carboxylic acid herbicides (PCAs) are difficult to degrade and, thus, pose significant threats to the environment and human health. The limit for 2,4-dichlorophenoxyacetic acid is 30 μg/L in China's standards for drinking water quality, 70 μg/L in the United States' drinking water standards, and 30 μg/L in the World Health Organization's guidelines for drinking water quality. Therefore, the development of an effective detection method for trace PCAs in water is a crucial endeavor. Metal-organic frameworks (MOFs) are novel porous materials that possess advantages such as a large specific surface area, adjustable pore size, and abundant active sites. They exhibit excellent adsorption capability for various compounds. However, the applications of MOFs as adsorbents are limited. For example, the process of isolating powdered MOFs from aqueous solutions is laborious, and microporous MOFs exhibit limited surface affinity, which decreases their mass transfer efficiency in the liquid phase. MOF crystals can be embedded in a substrate to overcome these limitations. Aerogels are obtained by drying hydrogels, which are hydrophilic polymers with a three-dimensional crosslinked network structure. Spongy aerogel materials exhibit unique structural properties such as high porosity, large pore volume, ultralow density, and easy tailorability. When MOFs are combined with an aerogel, their efficient and selective adsorption properties are preserved. In addition, MOF aerogels exhibit a hierarchical porous structure, which enhances the affinity and mass transfer efficiency of the MOF for target molecules. At present, MOF aerogels are primarily prepared by freeze-drying or using supercritical carbon dioxide. These drying processes require significant amounts of energy and time. Hence, the development of greener and more efficient methods to prepare skeleton aerogels is urgently needed. In this study, we prepared an environment-friendly aerogel at ambient temperature and pressure without the use of specialized drying equipment. This ambient-dried MOF composite aerogel was then used for the dispersive solid phase extraction (DSPE) of seven PCAs from environmental water, followed by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The key parameters affecting the efficiency of DSPE, including the extraction conditions, ratio of MIL-101(Fe)-NH2 to sodium alginate, pH of the aqueous samples, extraction time, ionic strength (salinity), and elution conditions, such as the elution solvent ratio, elution time, and elution volume, were investigated to obtain optimal extraction efficiency. The adsorbent could adsorb the target contaminants within 12 min, and the analytes could be completely desorbed within 30 s by elution with 4 mL of 1.5% (v/v) formic acid in methanol solution. The water samples could be analyzed without pH adjustment. The main adsorption mechanisms were electrostatic interactions and π-π conjugation. Thus, a new method based on MOF aerogels coupled with UHPLC-MS/MS was developed for the determination of the seven PCA residues in water. The calibration curves for the seven PCAs showed good linearity (r2≥0.9986), with limits of detection (LODs) and quantification (LOQs) ranging from 0.30 to 1.52 ng/L and from 1.00 to 5.00 ng/L, respectively. Good intra- and inter-day precision values of 6.5%-17.1% and 7.4%-19.4%, respectively, were achieved under low (8 ng/L), medium (80 ng/L), and high (800 ng/L) spiking levels. The developed method was applied to the detection of PCAs in surface water, seawater, and waste leachate, and the detected mass concentrations ranged from 0.6 to 19.3 ng/L. Spiked recovery experiments were conducted at mass concentrations of 8, 80, and 800 ng/L, and the recoveries ranged from 61.7% to 120.3%. The proposed method demonstrates good sensitivity, precision, and accuracy, and has potential applications in the detection of trace PCAs in environmental water.

Biomarker identification and risk assessment of cardiovascular disease based on untargeted metabolomics and machine learning

Cardiovascular disease (CVD) is the leading cause of mortality, disability, and healthcare costs, with a significant impact on the elderly and contributing to premature deaths across various age groups, including those below age 70. Despite decades of transformative discoveries and clinical efforts, the challenges of diagnosis, prevention, and treatment of CVD persist on a massive scale. This study aimed to unravel potential CVD-associated biomarkers and establish a machine learning model for the risk assessment of CVD. Untargeted metabolic assay with ultra-high performance liquid chromatography-tandem mass spectrometry and routine clinical biochemistry test were undertaken on the fasting venous blood specimens from 57 subjects. Four relevant clinical traits and 164 CVD-associated metabolites were identified, especially those related to glycerophospholipid metabolism and biosynthesis of unsaturated fatty acids. The machine learning model achieved from an integrated biomarker panel of palmitic amide, oleic acid, 138-pos (the 138th detected metabolomic feature in positive ion mode), phosphatidylcholine, linoleic acid, age, direct bilirubin, and inorganic phosphate, was able to improve the accuracy of CVD risk assessment up to a high satisfactory value of 0.91. The findings indicate that disorders in the metabolic processes of biological membranes and energy are significantly associated with increased risk of vascular damage in CVD patients. With machine learning methods, the pivotal metabolites and clinical biomarkers offer a promising potential for the efficient risk assessment and diagnosis of CVD.

Proteomic Profiling of Endothelial Cell Secretomes After Exposure to Calciprotein Particles Reveals Downregulation of Basement Membrane Assembly and Increased Release of Soluble CD59

Calciprotein particles (CPPs) are essential circulating scavengers of excessive Ca2+ and PO43− ions, representing a vehicle that removes them from the human body and precludes extraskeletal calcification. Having been internalised by endothelial cells (ECs), CPPs induce their dysfunction, which is accompanied by a remarkable molecular reconfiguration, although little is known about this process’s extracellular signatures. Here, we applied ultra-high performance liquid chromatography-tandem mass spectrometry to perform a secretome-wide profiling of the cell culture supernatant from primary human coronary artery ECs (HCAECs) and internal thoracic artery ECs (HITAECs) treated with primary CPPs (CPP-P), secondary CPPs (CPP-S), magnesiprotein particles (MPPs), or Ca2+/Mg2+-free Dulbecco’s phosphate-buffered saline (DPBS) for 24 h. Incubation with CPP-P/CPP-S significantly altered the profiles of secreted proteins, delineating physiological and pathological endothelial secretomes. Neither pathway enrichment analysis nor the interrogation of protein–protein interactions detected extracellular matrix- and basement membrane-related molecular terms in the protein datasets from CPP-P/CPP-S-treated ECs. Both proteomic profiling and enzyme-linked immunosorbent assay identified an increased level of protectin (CD59) and reduced levels of osteonectin (SPARC), perlecan (HSPG2), and fibronectin (FN1) in the cell culture supernatant upon CPP-P/CPP-S treatment. Elevated soluble CD59 and decreased release of basement membrane components might be considered as potential signs of dysfunctional endothelium.

A novel quantitative method for the determination of 10B-carrier boronophenylalanine in rat plasma by UHPLC-MS/MS and comparison with ICP-MS

L-Boronophenylalanine (BPA), a widely used 10B carrier for clinical boron neutron capture therapy (BNCT), was quantified in rat plasma through a simple, effective and stable ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method. Chromatographic separation was performed on an ACQUITY UPLC HSS T3 (100 mm × 2.1 mm, 1.8 μm) column with the mobile phase of 0.5 % formic acid aqueous solution and acetonitrile. For the detector, the m/z ion pairs used for quantification were 209.1→120.1 for BPA and 210.1→120.1 for internal standard in a positive mode by electrospray ionization (ESI) using multiple reaction monitoring (MRM). The method is specific and robust with rare affection by endogenous substances in the matrix. A good linear relationship was observed over 80–80000 ng/mL (r2 = 0.9993). The values of inter- and intra-day accuracy and precision were within the acceptance criteria of ±15 %. BPA was found to be stable under different experimental conditions. This developed method was successfully applied on a pharmacokinetic experiment on Sprague-Dawley rats (intravenous injection, 125 mg/kg) and a comparation between UHPLC-MS/MS and ICP-MS for BPA was carried out.

Citrullination Accompanies the Development of Carotid Atherosclerotic Plaques.

Citrullination represents a post-translational modification primarily mediated by peptidylarginine deiminase (PADI) 2 and 4 and resulting in the conversion of positively charged peptidylarginine to neutrally charged peptidylcitrulline. Molecular consequences of citrullination include the generation of neoepitopes which provoke the production of autoantibodies implicated in the development of autoimmune diseases. As citrullination initiates, promotes, and is enhanced by aseptic inflammation which plays a pivotal role in atherosclerosis, we proposed that citrullination might accompany the development of atherosclerotic vascular disease. To investigate features and patterns of citrullination in atherosclerotic plaques. We collected carotid atherosclerotic plaques (n = 14) and adjacent arterial segments (n = 14) which were pairwise excised during the carotid endarterectomy. The tissues were examined employing proteomic profiling (ultra-high performance liquid chromatography-tandem mass spectrometry analysis), haematoxylin and eosin staining, Western blotting and immunofluorescence staining for peptidylcitrulline, PADI2, and PADI4, and gene expression analysis. To better explore the mechanisms of citrullination in the neointima, we have also stained excised plaques for the extracellular vesicle markers (CD9 and CD81) and assessed co-localisation of PADI2 (a citrullination marker) with CD81 (an extracellular vesicle marker). In order to study the systemic response to citrullination in an atherosclerotic vascular disease setting, we measured the level of anti-citrullinated protein antibodies in the serum of patients with ischaemic stroke and healthy volunteers. Proteomic profiling found 213 plaque-specific and 111 intact arteria-specific proteins, as well as 46 proteins and 13 proteins which have been respectively upregulated or downregulated in plaques as compared with the adjacent intact segments. Among the top 20 upregulated proteins were atherogenic apolipoprotein B-100, iron-associated protein haptoglobin, and matrix metal-loproteinase-9, together indicating the advanced stage of plaque progression. In comparison with the intact arterial segments, plaques demonstrated protein signatures of innate immune response and oxidative stress, suggesting aseptic inflammation as a driver of atherosclerotic vascular disease. Both peptidylcitrulline and PADI2 have been abundant in the neointima but negligible in tunica media; further, the levels of peptidylcitrulline, PADI2, and PADI4 were elevated in plaque lysates in comparison with those from adjacent arterial segments (p = 0.025, 0.025, and 0.010, respectively). Notably, PADI2 and peptidylcitrulline were co-localised with the cells in the neointima and a considerable proportion of PADI2 was co-localised with CD81-positive extracellular vesicles (p = 0.003). Albeit citrullinated histone H3 and myeloperoxidase showed higher signal in the neointima than in tunica media (p = 0.048 and 0.023, respectively), we did not observe any signs of neutrophil extracellular traps (e.g., unwound chromatin or co-localisation of citrullinated histone H3 with neutrophil elastase) in the plaque tissue. Serum anti-citrullinated protein antibodies were not elevated in patients with ischaemic stroke (p = 0.71), suggesting that vascular citrullination likely does not trigger a generalised immune response. The development of carotid atherosclerosis is associated with citrullination, although it represents a local rather than systemic phenomenon in this clinical scenario.

Highly selective guanidine-linked covalent organic framework for efficient removal of perfluoroalkyl carboxylic acids from water samples

In this study, guanidine-linked covalent organic framework (TPDGCl) was synthesized via a solvothermal method. The presence of guanidine groups in its structure facilitates electrostatic interactions and provides hydrogen bonding sites, enabling the selective enrichment of perfluoroalkyl carboxylic acids (PFCAs) from environmental water samples. The material exhibits rapid kinetic mass transfer, which facilitates the efficient removal of samples containing PFCAs from aqueous solutions within 5 min. Furthermore, TPDGCl exhibits several advantageous properties, including high selectivity for PFCAs, a high adsorption capacity (2005 mg/g), excellent chemical stability, and remarkable recyclability (five cycles). Additionally, density functional theory (DFT) studies have demonstrated that the adsorption of PFCAs on TPDGCl is enhanced by ion exchange, hydrophobic interactions, hydrogen bonding interactions and ordered channel structures. Finally, TPDGCl was used as an adsorbent for dispersive solid-phase extraction (d-SPE), in combination with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), to develop an analytical method for the efficient extraction and sensitive detection of PFCAs. The developed method exhibits highly sensitivity, with detection and quantification limits of 0.64–0.85 ng/L and 2.6–3.4 ng/L, respectively. The recoveries of actual water samples ranged from 75.4% to 113.7%. Moreover, TPDGCl effectively reduces the levels of PFCAs in real water samples to less than 70 ng/L within only 1 h. These results indicate that TPDGCl is an effective adsorbent for removing PFCAs from environmental water samples.

Accurate determination of three new antihypertensive drugs illegally added to food using ultra-high performance liquid chromatography-tandem mass spectrometry

Effective strategies are required to address food safety issues related to the illegal addition of antihypertensive drugs to food and claims of antihypertensive function. In this study, a novel ultra-high performance liquid chromatography-triple-quadrupole mass spectrometry (UHPLC-MS/MS) method was developed for the simultaneous determination of three antihypertensive drugs (azilsartan, candesartan cilexetil, and lacidipine) in 12 food matrices (pressed candies, solid beverages, alternative teas, tea drinks, biscuits, jellies, mixed liquors, oral liquids, medicinal teas, tablets, hard capsules, and soft capsules). Initially, mass spectrometry parameters, such as the collision energies of the three antihypertensive drugs, were optimized. Subsequently, the response intensities and chromatographic separation conditions of the three drugs in different mobile phases were compared. In addition, to enhance the recoveries, various extraction solvents and purification methods, including solid-phase extraction (SPE) columns and the QuEChERS technique, were investigated. In the developed method, sample determination involved three steps. First, the sample was extracted using 0.2% (v/v) formic acid in acetonitrile and then filtered using high-speed centrifugation, in addition, the extracted solution of alternative tea and medicinal tea was purified using the QuEChERS technique. Second, the supernatant was diluted with water, and filtered through a 0.22 μm polytetrafluoroethylene (PTFE) membrane. Finally, the analytes were separated on an Agilent Eclipse Plus RRHD C18 column (50 mm×2.1 mm, 1.8 μm) using a 5 mmol/L ammonium formate aqueous solution and acetonitrile as the mobile phases under gradient elution conditions and then detected using UHPLC-MS/MS with positive electrospray ionization (ESI) in the multiple reaction monitoring (MRM) mode. Quantitative analysis was performed using a matrix-matched external standard method. Methodological validation showed good linear relationships for all three antihypertensive drugs in the investigated concentration ranges, with correlation coefficients (r2) greater than 0.996. The limit of detection (LOD) and limit of quantification (LOQ) of lacidipine were 0.02 mg/kg and 0.04 mg/kg, respectively, whereas those of the other two drugs were 0.01 mg/kg and 0.02 mg/kg, respectively. In the 12 food matrices, the average recoveries of the drugs ranged from 86.6% to 107.5% with relative standard deviations (RSDs) of 1.1%-10.9% (n=6) at low, medium, and high spiked levels. Furthermore, this method was successfully applied to the analysis of real food samples. Overall, the newly developed method is simple, rapid, sensitive, accurate, and suitable for the qualitative and quantitative determination of antihypertensive drugs in different food matrices. This work could provide technical support for food safety agencies in implementing measures against the illegal addition of antihypertensive drugs to food.

Influences of lactic acid bacteria strains on the flavor profiles, metabolites and quality characteristics of red yeast rice produced by solid-state fermentation

Red yeast rice (RYR) as a traditional fermented food produced by inoculation of the Monascus genus into steamed rice through solid-state fermentation, has been used intensively for thousands of years in China. Herein, we investigated the flavor profiles, metabolites and quality characteristics of RYR produced by mix fermentation with lactic acid bacteria (LAB) using the headspace solid phase microextraction gas chromatography–mass spectrometry (HS–SPME–GCMS) approach integrated with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC–MS). 56 volatile organic compounds (VOCs) and 1287 non-volatile metabolites were identified and classified into eight classes, the inoculation of Lactiplantibacillus plantarum (LP) and Limosilactobacillus fermentum (LF) increased VOCs and enhanced the flavor characteristics of RYR, with LP being the more significant. The KEGG pathway enrichment analysis revealed that most of the differential metabolites were enriched in amino acid metabolism when integrating volatile and non-volatile omics data, meanwhile, the addition of LAB promoted the metabolism of amino acid, alcohols, fatty acid and some flavonoids, in particular, amino acid metabolism was almost upregulated in the LP group. Therefore, this study highlights the tremendous potential of LAB in improving the flavor quality of RYR. This study provides novel insights into RYR fermentation processes and establishes a theoretical foundation for developing and applying new RYR products.

Optimization of skin sampling based on tape stripping for lipidome analysis by nanoflow ultrahigh performance liquid chromatography-tandem mass spectrometry

In this study, skin sampling by tape stripping for lipid analysis was optimized by examining the lipid profiles of the stratum corneum (SC), focusing on the composition and levels of ceramides (Cer), diacylglycerols (DG), and triacylglycerols (TG), using nanoflow ultrahigh performance liquid chromatography-tandem mass spectrometry. Significant variations in the number and composition of the identified lipids, particularly Cer and neutral lipid species, were observed across different skin locations, including the forearm, forehead, cheek, and neck. Analysis of the layer-to-layer lipid profiles of the seven consecutive layers revealed a gradual decrease in DG and TG levels from the outermost to the innermost layers, with certain Cer subclasses showing increases in the second to fourth layers and subsequent decreases. Comparative analysis of lipid profiles from adjacent spots demonstrated statistical consistency and persistent differences between spots. Pooling layers were evaluated as an alternative method for representing SC layers, and their efficiencies were assessed by varying the number of pooled layers. We found that pooling five consecutive layers was effective in terms of the number and levels of identified lipids. Additionally, investigations into the matrix effect and extraction efficiency upon pooling layers indicated that pooling up to five layers did not significantly affect ionization suppression or reduce extraction recovery.

Associations of Advanced Glycation End Products with Sleep Disorders in Chinese Adults.

Advanced glycation end products (AGEs), a group of food processing byproducts, have been implicated in the development of various diseases. However, the relationship between circulating AGEs and sleep disorders remains uncertain. This cross-sectional study elucidated the association of plasma AGEs with sleep disorders among 1732 Chinese adults who participated in the initial visit (2019-2020) of the Tongji-Shenzhen Cohort (TJSZC). Sleep behavior was assessed using self-reported questionnaires and precise accelerometers. Plasma levels of AGEs, including Nε-(Carboxymethyl)lysine (CML), Nε-(Carboxyethyl)lysine (CEL), and Nδ-(5-hydro-5-methyl-4-imidazolone-2-yl)-ornithine (MG-H1), were quantified by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). In logistic regression, per IQR increment in individual AGEs was associated with an increased odds ratio of short sleep duration (CML: 1.11 [1.00, 1.23]; CEL: 1.16, [1.04, 1.30]), poor sleep quality (CML: 1.33 [1.10, 1.60]; CEL: 1.53, [1.17, 2.00]; MG-H1: 1.61 [1.25, 2.07]), excessive daytime sleepiness (CML: 1.33 [1.11, 1.60]; MG-H1: 1.39 [1.09, 1.77]), and insomnia (CML: 1.29 [1.05, 1.59]). Furthermore, in weighted quantile sum regression and Bayesian kernel machine regression analyses, elevated overall exposure levels of plasma AGEs were associated with an increased risk of sleep disorders, including short sleep duration, poor sleep quality, excessive daytime sleepiness, and insomnia, with CML being identified as the leading contributor. Insufficient vegetable intake and higher dietary fat intake was associated with an increase in plasma CEL. These findings support a significant association between plasma AGEs and sleep disorders, indicating that AGEs may adversely influence sleep health and reducing the intake of AGEs may facilitate preventing and ameliorating sleep disorders.

Efficient Elimination of Matrix Effects for the Rapid Screening of β-Agonist Residues in Porcine Urine by Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS/MS)

An efficient and innovative clean-up method was developed for the rapid screening of β-agonists residues in porcine urine by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). 1% Aqueous ammonium hydroxide was shown to be effective for the removal of matrix components as a wash step in solid phase extraction (SPE). A significant reduction in matrix effects was observed with values from 81% to 108%. Furthermore, under the optimized conditions, the recoveries of all analytes at 0.3, 0.6, and 3.0 μg/L ranged from 70.1% to 109.0% when employing the external standard method for quantitative analysis, rather than relying on matrix-matched standards or isotope-labelled internal standards to mitigate matrix effects. The limits of detection (LOD) and limits of quantification (LOQ) were 0.1 μg/L and 0.3 μg/L, respectively. This method has been successfully applied to screen β-agonists in porcine urine and is a promising tool for multi-residue analysis.

Bioaccessibility and antioxidant activity of fermented chrysanthemum rice wine on In vitro simulated digestion

The purpose of this study was to investigate the bioaccessibility of total phenolic (TPC), total flavonoid (TFC), chlorogenic acid and antioxidant activity in fermented chrysanthemum rice wine (FRW) under in vitro gastrointestinal digestion model compared with rice wine (RW). The fermented samples were digested and the bioactive components and antioxidant activity during gastric phase (GP) and intestinal phase (IP) were analyzed. The results showed that TPC, TFC, ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and oxygen radical absorbance capacity (ORAC) decreased during the gastrointestinal digestion stage. TFC was higher in FRW during in vitro gastrointestinal digestion stage and increased to a maximum of 0.483 mg/mL at IP stage. 2.2- azinobis-3- ethyl-benzothiazoline-6 - sulfonic acid (ABTS) reached its maximum value of 91.62% in the late stage of intestinal digestion. The hydroxyl radical scavenging activity (HRSA) increased to 77.94% in the IP-2 phase. In addition, a total of 158 (FRW) and 131 (RW) polyphenols, including flavonoids, isoflavones, phenols and coumarins, were detected and identified by Ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS) analysis. The biotransformation was carried out between the isomers of phenolic compounds in FRW, where 4,5-dicaffeoylquinic acid might be changed into neochlorogenic acid and chlorogenic acid. Correlation analysis showed that 46.15% of metabolites in FRW were positively correlated with the decrease of DPPH, FRAP and ORAC, while 53.85% were positively correlated with the increase of ABTS and HRSA. The results showed higher bioavailability and antioxidative activity in FRW after in vitro digestion.

Antinociceptive in vivo activity and chemical profiling by UHPLC-MS/MS of stem bark and leaves extracts of Ficus maxima Mill. (Moraceae)

Ethnopharmacological relevanceFicus maxima is a medicinal plant extensively used in traditional medicine by Indigenous peoples across Central and South America. It is a member of the family Moraceae, subgenus Pharmacosycea, employed in treating various conditions, including intestinal parasites, gingivitis, internal inflammations, and snake bites. Despite its significant pharmacological potential, the species remains underrepresented in scientific literature. Aim of the studyThis study aimed to evaluate the in vivo antinociceptive properties of leaf (ELFM) and stem bark (EBFM) extracts from Ficus maxima. Additionally, the chemical composition of these extracts was determined using ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Materials and methodsPlant material was collected in Abaetetuba, Pará, Brazil, in October 2013 and subjected to static maceration to obtain crude ELFM and EBFM. Bio-guided fractionation was performed by sequential liquid-liquid partitioning with hexane (Hex), dichloromethane (DCM), and ethyl acetate (EtOAc), yielding the following fractions: ELFM-Hex and EBFM-Hex, ELFM-DCM and EBFM-DCM, and ELFM-EtOAc and EBFM-EtOAc. The biological activity of EBFM, ELFM, and their respective fractions were evaluated using the formalin-induced pain test and the hot plate test, followed by an assessment of their mechanisms of action. The UHPLC-MS/MS analysis was conducted using electrospray ionization (ESI) in both positive and negative modes. Metabolite annotation was facilitated by MS/MS libraries and molecular networks constructed on the GNPS platform. ResultsThe reactivity time to formalin in the neurogenic phase was reduced from 84.7 ± 7.6 s (100%) to 37.3 ± 4.7 s (44%), 33.1 ± 6.3 s (39%), 40.7 ± 7.4 s (48%), 57.2 ± 2.6 s (77%), 49.7 ± 4.1 s (58%), 46.8 ± 8.1 s (55%), and 52.4 ± 5.3 s (61%) after treatment with ASA, morphine, EBFM, ELFM, ELFM-Hex, ELFM-DCM, and ELFM-EtOAc at doses of 30 mg/kg, respectively. In the inflammatory phase, the reactivity time to formalin was reduced from 124.3 ± 25.9 s (100%) to 49.7 ± 4.7 s (40%), 9.8 ± 4.3 s (8%), 32.5 ± 8.5 s (26%), 59.8 ± 16.8 s (48%), and 54.4 ± 7.3 s (44%) after treatment with ASA, morphine, EBFM, ELFM, and ELFM-Hex at doses of 30 mg/kg, respectively. A reversal of the antinociceptive action of EBFM and ELFM was observed in the inflammatory phase after treatment with atropine, a muscarinic antagonist, and naloxone, an opioid antagonist, respectively. In the hot plate test, EBFM showed Antinociceptive Activity (AA) of 62.6 ± 9.2% after 90 min; however, there was a reversal of AA to 8.6 ± 2.8% when naloxone was used. The UHPLC-MS/MS metabolite analysis revealed the presence of loliolide (3), luteolin (13), lupeol (14), gallic acid (15), chlorogenic acid (16), pygenic acid A (17), and other metabolites from the alkaloids and fatty acids classes.

Excretion characteristics of main compounds of Yigong San in urine, feces, and bile of rats.

Yigong San (YGS) is a traditional Chinese medicine formula used for pediatric anorexia, chronic atrophic gastritis, and irritable bowel syndrome. In this study, the excretion of eight main compounds, including liquiritin; isoliquiritin; hesperidin;ginsenosides Rb1, Re, and Rg1; and atractylenolides I and II, in rat urine, feces, and bile, was investigated by ultra-high performance liquid chromatography-tandem mass spectrometry. The results showed that the cumulative excretion rates of the compounds in rat urine, feces, and bile were 0.018-1.15%, 0.024-19.89%, and 0.0025-0.72%, respectively. Among the eight compounds detected, liquiritin was the richest in urine, and ginsenosides Re and Rg1 and atractylenolide I were mainly found in feces and bile. In summary, the main components of YGS are excreted via multiple approaches. Liquiritin is mainly through urine, whereas isoliquiritin;hesperidin;ginsenosides Rb1, Re,and Rg1; and atractylenolides I and II are mainly through feces. The excretion of these compounds in bile is usually positively correlated with that in feces. This study lays a foundation for further pharmacological research and application of YGS.

Eco-friendly one-step egg white gel preparation for sensitive detection of 13 trichothecenes in oats using UHPLC-MS/MS.

Oat products have gained widespread recognition as a health food due to their rich and balanced nutritional profile and convenience. However, the unique matrix composition of oats, which differs significantly from other cereals, presents specific challenges for mycotoxin analysis. This study presents an ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method enhanced with an innovative egg white gel pretreatment for the simultaneous analysis of 13 regulated and unregulated trichothecenes in oats. The method demonstrated excellent performance with high accuracy (> 87.5%), repeatability (< 5.7%), and reproducibility (< 8.1%). Analysis of 100 commercial oat products revealed a concerning detection rate (78%) for at least one of the 11 trichothecenes investigated. Notably, deoxynivalenol, exceeding the standard limit in 2% of samples, exhibited the highest detection rate (62%). Additionally, concerning co-occurrence patterns and positive correlations were observed, highlighting potential synergistic effects. The first-time detection of unregulated mycotoxins (T-2 triol, 4,15-diacetoxyscirpenol, 15-acetoxyscirpenol, and neosolaniol) underscores the need for comprehensive monitoring. This method, while developed for oats, shows potential for broader application to other cereals, though further investigation and confirmation are necessary. These findings suggest a potentially underestimated risk of trichothecenes in oats, necessitating continuous monitoring to ensure consumer safety.

Simultaneous determination of icotinib, osimertinib, aumolertinib, and anlotinib in human plasma for therapeutic drug monitoring by UPLC-MS/MS

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) such as icotinib, osimertinib, and aumolertinib have emerged as promising treatment options for EGFR mutated Non-small cell lung cancer (NSCLC) patients. Additionally, anlotinib, an anti-angiogenic agent targeting VEGFR, FGFR, and PDGFR, has been used in combination with EGFR-TKIs in NSCLC cases. A method utilizing ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed and validated for quantifying icotinib, osimertinib, aumolertinib and anlotinib simultaneously in clinical TDM. The chromatographic separation was performed using a Kinetex C18 column (100 mm × 2.1 mm) and an elution gradient of ammonium acetate in water acidified with 0.1 % formic acid and in acetonitrile. The assay was validated over a linear range of 4–2000 ng/mL for icotinib, 2–1000 ng/mL for osimertinib, 1–500 ng/mL for aumolertinib, and 0.8–400 ng/mL for anlotinib, following the guidelines on bioanalytical methods by FDA. The quantification method exhibited satisfactory performance in terms of selectivity, accuracy (from 91.3 % to 107 %), precision (intra- and inter-day coeffficients of variation ranged from 0.944 % to 7.48 %), linearity, recovery (from 86.0 % to 91.9 %), matrix effect (IS-normalized matrix factors were from 96.7 % to 102 %), and stability. Overall, the method proved to be sensitive, reliable, and straightforward, enabling successful simultaneous determination of blood concentrations of icotinib, osimertinib, aumolertinib, and anlotinib in patients. The validity of the method has been confirmed across various instruments.

P-glycoprotein-mediated herb-drug interaction evaluation between Tenacissoside G and paclitaxel.

P-glycoprotein (P-gp)-mediated herb-drug interactions (HDIs) may impact drug efficacy and safety. Tenacissoside G (Tsd-G), a major active component of Marsdenia tenacissima, exhibits anticancer activity. To analyze the effect of Tsd-G on the pharmacokinetics of paclitaxel (PTX), researchers selected 30 Sprague-Dawley (SD) rats, randomized into a solvent control group, a verapamil positive control group, and 20, 40, and 60 mg/kg Tsd-G groups. After seven consecutive days of intraperitoneal injection of verapamil or Tsd-G, a single dose of 6 mg/kg PTX was injected intravenously. Plasma samples were collected at different time points, and proteins were precipitated using a methanol-acetonitrile solution. An ultrahigh-performance liquid chromatography-tandem mass spectrometry method was developed, with docetaxel as an internal standard, and quantified using positive ion multiple reaction monitoring (MRM) mode. This analytical method's specificity, accuracy, precision, recovery, matrix effect, and sample stability meet the requirements for biological sample determination. After Tsd-G administration in rats, the mean residence time of PTX was significantly prolonged. And Tsd-G can stably bind to P-gp by forming hydrogen bonds and inhibiting the expression of P-gp in rat liver. Although the metabolites of PTX were not detected in this study, the above results still indicate the existence of HDIs between Tsd-G and PTX, and P-gp may be the main target to mediate HDIs.

Determination of hexachlorophene residue in fruits and vegetables by ultra-high performance liquid chromatography-tandem mass spectrometry.

A modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) -LC-MS/MS method was developed for the determination of hexachlorophene in fruits and vegetables. Samples were extracted by acetonitrile and then salted with an acetate buffer system. Extractants neutral alumina (Al-N), strong cation exchange silica gel bonded adsorbent (SCX) and graphitized carbon black (GCB) were used for sample purification. The method demonstrates excellent accuracy and reproducibility. Under optimized conditions, the correlation coefficients of hexachlorophene were higher than 0.995 in the range of 0.5-20 ng/mL. The limit of quantification (LOQ) was 2.0 μg/kg. The average recoveries, assessed at three spiked levels (2.0, 4.0, and 20.0μg/kg) across various matrices including cabbage, celery, tomato, eggplant, potato, radish, cowpea, chives, apple, peach, grape, citrus, bitter melon, banana and hami melon ranged from 72.0 to 100.5% with relative standard deviations from 3.2 to 9.8% (n = 6).

Identification of Secondary Metabolites by UHPLC-ESI-HRMS/MS in Antifungal Strain Trichoderma harzianum (LBAT-53).

Trichoderma spp. are filamentous fungi generally observed in nature, which are widely marketed as biocontrol agents. The secondary metabolites produced have obtained special attention since they possess attractive chemical structures with a broad spectrum of biological activities. In Cuba, the species of Trichoderma have been commercially applied for the control of several phytopathogens to protect agricultural crops, but few studies have been carried out to detect and characterize the production of metabolites with biological activity. The strain Trichoderma harzianum LBAT-53 was subjected to an antifungal in vitro assay against Fusarium oxysporum f.sp. cubense by dual culture and volatile metabolite assays and fermented in PDB under constant agitation conditions. The ethyl acetate crude extract was obtained by liquid-liquid extraction. The fungal extract was investigated for the composition of secondary metabolites through chemical screening and ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) in negative ionization mode. As a result, LBAT-53 showed antagonistic activity in vitro (Class 2) against the pathogen evaluated in direct confrontation (76.9% of inhibition in 10 days) and by volatile metabolites (<40% in 7 days). Furthermore, seven low-molecular-weight phenolic compounds, including chrysophanol, phomarin, endocrocin, and trichophenol A, among others, were identified using UHPLC-ESI-MS/MS. This study is the first work on the characterization of secondary metabolites produced by the commercially applied strain LBAT-53, which is a promising source of bioactive compounds. These results provide a better understanding of the metabolism of this fungus, which is widely used in Cuba as biopesticides in agriculture pest control.