bims-metlip Biomed News
on Methods and protocols in metabolomics and lipidomics
Issue of 2024–11–24
fifty-one papers selected by
Sofia Costa, Matterworks
  1. Development and application of an LC-MS/MS method for the combined quantification of oxysterols and bile acids.
  2. Leveraging supported liquid extraction and automated workflow for high efficiency and high quality clinical LC-MS/MS method for quantification of urinary 5-hydroxyindoleacetic acid (5-HIAA), vanillylmandelic acid (VMA) and homovanillic acid (HVA).
  3. Effect of different pooled qc samples on data quality during an inter-batch experiment in untargeted UHPLC-HRMS analysis on two different MS platforms.
  4. Simultaneous Quantitation of Multiple Biological Thiols Using Reactive Ionization and Derivatization with Charged Mass Tags.
  5. Probe electrospray ionization coupled to a quadrupole time-Of-flight: A feasibility study for the detection of cocaine and its derivatives in oral fluid.
  6. Studying Structural Details in Complex Samples. I. Combining two Chromatographic Separation Methods with Ultrahigh Resolution Mass Spectrometry.
  7. Improved ion detection sensitivity in mass spectrometry imaging using tapping-mode scanning probe electrospray ionization to visualize localized lipids in mouse testes.
  8. Determination of Hormonal Growth Promotants in Beef Using Liquid Chromatography-Tandem Mass Spectrometry.
  9. Protocol for a low-volume, direct analysis urine preparation procedure for non-targeted GC-MS metabolomics.
  10. The microbiome diversifies N -acyl lipid pools - including short-chain fatty acid-derived compounds.
  11. Data Processing of Product Ion Spectra: Methods to Control False Discovery Rate in Compound Search Results for Untargeted Metabolomics.
  12. Development and validation of ultra-performance liquid chromatography tandem mass spectrometry methods for the quantitative analysis of the antiparasitic drug DNDI-6148 in human plasma and various mouse biomatrices.
  13. A Validated Liquid Chromatography-Tandem Mass Spectrometry Method for the Determination of Methylophiopogonanone A in Rat Plasma and Its Application to Pharmacokinetic Study.
  14. Simple and rapid analytical method for the determination of methylmercury in fish and shellfish using solid-phase extraction and gas chromatography-mass spectrometry.
  15. Advanced high-resolution chromatographic strategies for efficient isolation of natural products from complex biological matrices: from metabolite profiling to pure chemical entities.
  16. Predicting Tandem Mass Spectra of Small Molecules Using Graph Embedding of Precursor-Product Ion Pair Graph.
  17. Cortisol quantification in human plasma and urine by liquid chromatography coupled to mass spectrometry: Validation, analysis and application in a reference population and patients with adrenal incidentalomas.
  18. EigenRF: an improved metabolomics normalization method with scores for reproducibility evaluation on importance rankings of differential metabolites.
  19. A Sterol Panel for Rare Lipid Disorders: Sitosterolemia, Cerebrotendinous Xanthomatosis and Smith-Lemli-Opitz Syndrome.
  20. Postionization Mass Spectrometry Imaging: Past, Present, and Future.
  21. Application of UHPLC-ESI-MS/MS to Identify Free Radicals via Spin Trapping with BMPO.
  22. Identification of novel microcystins in algal extracts by a liquid chromatography-high-resolution mass spectrometry data analysis pipeline.
  23. Determination of furmonertinib in human plasma and cerebrospinal fluid by UPLC-MS/MS: Application in lung cancer patients with and without brain metastasis.
  24. Visualizing active fungicide formulation mobility in tomato leaves with desorption electrospray ionisation mass spectrometry imaging.
  25. A Tool for Reaction Monitoring in Real Time, the Development of a "Walk-Up Automated Reaction Profiling" System.
  26. Identification and quantification of the molecular species of bilirubin BDG, BMG and UCB by LC‒MS/MS in hyperbilirubinemic human serum.
  27. Evaluation of the ionization efficiency in phosphatidylcholine positional isomers with docosahexaenoic acid bound to the sn-1 or sn-2 position.
  28. PyINETA: Open-Source Platform for INADEQUATE-JRES Integration in NMR Metabolomics.
  29. MassSpecGym: A benchmark for the discovery and identification of molecules.
  30. Discovery of Acylated Glycine and Alanine by Integrating Chemical Derivatization-Based LC-MS/MS and Knowledge-Driven Prediction.
  31. Development of deep learning software to improve HPLC and GC predictions using a new crown-ether based mesogenic stationary phase and beyond.
  32. Analysis of inorganic arsenic and methylarsenic in soil after derivatization by gas chromatography-mass spectrometry.
  33. Green RP-HPLC method for the estimation of carfilzomib in bulk, protein nanocarriers and human plasma: Application of chemometrics and Monte-Carlo simulations.
  34. Evaluation of various mass spectrometry mode based on gas chromatography for quantifying the polycyclic aromatic hydrocarbon metabolites in human urine.
  35. Utilizing two-dose difference combined with stable isotope tracing for effective and comprehensive metabolite identification of pioglitazone via ultra-high-performance liquid chromatography-mass spectrometry.
  36. Determination of Sennoside A in Rat Plasma by Liquid Chromatography/Electrospray Ionization Tandem Mass Spectrometry and Its Application to a Rat Pharmacokinetic Study.
  37. Validation of the QuEChERSER Method for 245 Pesticides and Environmental Contaminants in Barley and Hemp by Low-Pressure GC: Comparison of Triple Quadrupole MS/MS and Orbitrap HRMS for Qualitative and Quantitative Analysis.
  38. A new chromatographic method for the determination of cysteine, glutathione, homocysteine and Nɛ-homocysteinyllysine isopeptide in human plasma.
  39. Finding the ideal solvent for the analysis of polar analytes using supercritical fluid chromatography.
  40. NIRSpredict: a platform for predicting plant traits from near infra-red spectroscopy.
  41. FraMiTrACR: A Sustainable and Economical Technology for Analytical Sample Preparation.
  42. Enhanced industrial wastewater monitoring: method development for non-target screening of highly polar substances using ZIC-HILIC-HRMS.
  43. In vino veritas: A metabolomics approach for authenticating Provence Rosé wines.
  44. MetaboScope: a statistical toolbox for analyzing 1H nuclear magnetic resonance spectra from human clinical studies.
  45. Room-temperature synthesis of fluorinated covalent organic framework coupled with liquid chromatography-mass spectrometry for determination of per- and polyfluoroalkyl substances in drinking water.
  46. A Simple and Rapid HPLC Method Development for Quantification of Sodium Benzoate Content in Chlorzoxazone Oral Solid Dosage Forms.
  47. Green HPLC method for determination of paracetamol and ibuprofen in human plasma: applications to pharmacokinetics.
  48. Detection of Salmonella enterica in food using targeted mass spectrometry.
  49. Optimizing conditions in online RPLC × SFC for the analysis of complex samples containing neutral compounds: Solving injection issues.
  50. Investigating the Kinetics of Heterogeneous Lipid Ozonolysis by an Online Photoionization High-Resolution Mass Spectrometry Technique.
  51. Designing boron-doped carbon dot-functionalized COFs for fluorescence screening and liquid chromatography tandem mass spectrometry detection of toxins.
  1. J Lipid Res. 2024 Nov 16. pii: S0022-2275(24)00202-5. [Epub ahead of print] 100697
    Development and application of an LC-MS/MS method for the combined quantification of oxysterols and bile acids.
    Martin Roumain, Giulio G Muccioli.
      Oxysterols and bile acids are interconnected bioactive lipids playing pivotal roles in diverse physiological and pathological processes. For this reason, they are increasingly studied together for their implications in various diseases. However, due to analytical challenges inherent to the nature of these analytes, very few methods have been developed for the simultaneous analysis of these lipids. We here report the development of a sensitive LC-MS/MS method for the combined quantification of 18 oxysterols, 11 unconjugated, 15 conjugated bile acids, and 1 bile acid precursor, using 8 isotope-labeled internal standards, addressing the need for a more comprehensive analysis of these interesting lipid families. During the method development, we investigated different extraction protocols, set up a purification step and achieved chromatographic separation for these lipids, overcoming challenges such as the large number of analytes, isomers, and wide range of polarity across the analytes. Finally, the method was successfully applied to the analysis of preclinical and clinical samples, quantifying 12 oxysterols and 14 bile acids in human plasma, 10 oxysterols and 18 bile acids in mouse plasma from the vena cava, and 10 oxysterols and 20 bile acids in mouse plasma from the portal vein within a single chromatographic run.
    Keywords:  25-hydroxycholesterol; 4β-hydroxycholesterol; Lipidomics; cholesterol metabolism; cytochrome P450; deoxycholic acid; lipids; liquid chromatography mass spectrometry; sterols; ursodeoxycholic acid
    DOI:  https://doi.org/10.1016/j.jlr.2024.100697
  2. Clin Chim Acta. 2024 Nov 19. pii: S0009-8981(24)02310-6. [Epub ahead of print] 120057
    Leveraging supported liquid extraction and automated workflow for high efficiency and high quality clinical LC-MS/MS method for quantification of urinary 5-hydroxyindoleacetic acid (5-HIAA), vanillylmandelic acid (VMA) and homovanillic acid (HVA).
    Difei Sun, Dawn-Marie Murphy McLean, Jan Palaty, Danijela Konforte.
       BACKGROUND AND AIMS: 5-hydroxyindoleacetic acid (5-HIAA), vanillylmandelic acid (VMA) and homovanillic acid (HVA) are neurotransmitter metabolites used for the diagnosis and monitoring of neuroendocrine tumors. This study's objective was to apply automation to improve efficiency and quality of a liquid chromatography tandem mass spectrometry (LC-MS/MS) procedure for quantification of 5-HIAA, VMA and HVA in human urine.
    METHODS: 5-HIAA, VMA and HVA in urine samples were extracted with automated supported liquid extraction (SLE) and quantified by LC-MS/MS utilizing scheduled multiple reaction monitoring (MRM). An in-house developed middleware was used to automate data analysis and reporting.
    RESULTS: The average recovery for 5-HIAA, VMA and HVA in different types of urine matrix varied between 92.5 % and 99.0 %, while the average matrix factor varied between 98.6 % and 103.4 %. The results of other validation studies: stability, sensitivity, analytical measurement range, selectivity, accuracy, precision, dilution verification, carryover, and method comparison all met the performance criteria.
    CONCLUSIONS: Automated SLE is a suitable sample preparation technique for quantification of 5-HIAA, VMA and HVA in human urine. Workflow automation described in this study resulted in 54 % of overall time savings and 80 % of hands-on time savings compared to all manual approach.
    Keywords:  5-hydroxyindoleacetic acid (5-HIAA); Homovanillic acid (HVA); Liquid chromatography tandem mass spectrometry (LC-MS/MS); Supported liquid extraction (SLE); Vanillylmandelic acid (VMA); Workflow automation
    DOI:  https://doi.org/10.1016/j.cca.2024.120057
  3. Anal Bioanal Chem. 2024 Nov 18.
    Effect of different pooled qc samples on data quality during an inter-batch experiment in untargeted UHPLC-HRMS analysis on two different MS platforms.
    Mélina Ramos, Valérie Camel, Even Le Roux, Soha Farah, Mathieu Cladiere.
      Quality control (QC) samples are commonly used in metabolomics approaches for three main reasons: (i) the initial conditioning of the column; (ii) the correction of analytical drift especially between batches; and (iii) the evaluation of measurement precision. In practice, there are several ways to prepare and conserve QC samples. The most common in untargeted metabolomics is to pool samples after or before extraction, in order to obtain pooled QC samples accounting, respectively, for analytical variance or for both analytical and sample preparation variances. In this study, focusing on untargeted analysis of tea (Camellia sinensis) leaves, we compared three ways of preparing pooled QC samples (two usual and one unusual QC sample preparations) and their efficiency to improve data quality in terms of inter-batch correction, measurement precision, and VIP candidates selection on datasets obtained using two mass spectrometry (MS) technologies (Orbitrap and time of flight (QToF)). We also investigated the effect of data processing modalities, based on the different QC preparations, on data loss and on the global structure of the datasets. Generally, our results show that usual QC sample preparation leads to comparable datasets quality in terms of precision and dispersion on both MS instruments. They also show that QC preparation is crucial for VIP selection; in fact, up to 54% of biomarkers candidates were specific of the QC preparation type used for data processing.
    Keywords:  Inter-batch correction; Liquid chromatography (LC); Mass spectrometry (MS); Non-targeted analyses; Quality control (QC); Tea leaves (dry)
    DOI:  https://doi.org/10.1007/s00216-024-05646-6
  4. Anal Chem. 2024 Nov 21.
    Simultaneous Quantitation of Multiple Biological Thiols Using Reactive Ionization and Derivatization with Charged Mass Tags.
    Mousumi Saha, Lingqi Qiu, Yu Han-Hallett, Christopher J Welch, R Graham Cooks.
      The biologically important thiols (cysteine, homocysteine, N-acetyl cysteine, and glutathione) are key species in redox homeostasis, and there is a clinical need to measure them rapidly, accurately, and simultaneously at low levels in complex biofluids. The solution to the challenge presented here is based on a new derivatizing reagent that combines a thiol-selective unit to optimize the chemical transformation and a precharged pyridinium unit chosen to maximize sensitivity in mass spectrometry. Derivatization is performed simultaneously with ionization ("reactive ionization"), and mass spectrometry is used to record and characterize the thiol reaction products. The method is applicable over the concentration range from 1 μM to 10 mM and is demonstrated for 25 blood serum, 1 plasma, and 3 types of tissue samples. The experiment is characterized by limited sample preparation (<4 min) and short analysis time (<1 min). High precision and accuracy (both better than 8%) are validated using independent HPLC-MS analysis. Cystine-cysteine redox homeostasis can be monitored by introducing an additional reduction step, and the accuracy and precision of these results are also validated by HPLC-MS.
    DOI:  https://doi.org/10.1021/acs.analchem.4c03807
  5. J Pharm Biomed Anal. 2024 Nov 15. pii: S0731-7085(24)00610-1. [Epub ahead of print]254 116568
    Probe electrospray ionization coupled to a quadrupole time-Of-flight: A feasibility study for the detection of cocaine and its derivatives in oral fluid.
    Elisa Jousselin, Elies Zarrouk, Pauline Griffeuille, Sylvain Dulaurent, Souleiman El Balkhi, Franck Saint-Marcoux.
      Probe Electrospray Ionization (PESI) is an atmospheric pressure ionization method that can be directly coupled with a mass spectrometer to allow ultrafast analyses without chromatographic separation and with minimal sample preparation. Using the particular case of cocaine and its metabolites in human oral fluid, the main objective of the present study was to test the feasibility of a new hybrid system combining a PESI source and a quadrupole time-of-flight (QTOF). The best results were obtained for a sample preparation with a simple dilution of 100 µL of oral fluids in an ethanol / 10 mM ammonium formate buffer (50/50) and 10 µL deposited on a dedicated sample plate and introduced into the PESI source. For HRMS acquisition, an approach consisting in a full-mass scan ("untargeted approach" from 100 to 500 m/z; MS1) followed by a targeted scheduled MSMS acquisition (precursor ions of the 3 molecules of interest and their 3 internal standards; MS2) gave the best signals. The total time of analysis was 0.45 min and the method was validated according to ISO15189 standard for a 5-100 ng/mL range, including accuracy and precision (inter-day and intra-day precision and bias values were lower than 15 %), matrix effect, carryover and specificity (no interference with a mixture of 119 psychotropic drugs spiked at 1 mg/L). The LLOD values were 1 ng/mL for the 3 cocaine derivatives and 83 Driving Under the Influence of Drug (DUID) cases sent to our Lab for the determination of illicit drugs in oral fluid were analyzed using the PESI-QTOF method and compared to a LC-MS/MS method. A perfect agreement was observed between the 2 methods, whether the cases were positive or negative. Cocaine was detected in 51 out of these 83 real cases (61.6 %). BZE and EME were also simultaneously detected in 50 of them (98.5 %). This feasibility study reports the first analytical method based on a coupling of a PESI source to a QTOF mass spectrometer. Adding the major advantage of high specificity through HRMS is a step forward for PESI technology.
    Keywords:  Cocaine; High resolution mass spectrometry; Oral fluid; Probe electrospray ionization
    DOI:  https://doi.org/10.1016/j.jpba.2024.116568
  6. J Am Soc Mass Spectrom. 2024 Nov 18.
    Studying Structural Details in Complex Samples. I. Combining two Chromatographic Separation Methods with Ultrahigh Resolution Mass Spectrometry.
    Jens Dreschmann, Lilla Molnarne Guricza, Wolfgang Schrader.
      The analysis of complex mixtures poses a challenge due to the high number of compounds present in a mixture, which often exceed the capabilities of analytical methods and instruments. Even more challenging is understanding the structural details of compounds within a complex sample. Most analytical methods provide just bulk information on complex samples, and individual structural details cannot be observed. High-resolution mass spectrometry, the best method to analyze complex samples, suffers from inherent problems for structural studies in complex systems because collision-induced fragmentation (CID) measurements cannot provide data from individual compounds alone. The combination of different steps of chromatographic separation, here the combination of size exclusion chromatography with argentation chromatography, provides sufficient reduction in complexity to implement a method that allows gaining structural details of individual compounds within a complex mixture. The combination of offline size exclusion chromatography followed by online argentation chromatography effectively creates fractions based on the respective properties of the compounds in the mixture (size and number of π-bonds and heteroatoms) and reduces matrix effects to a great extent. Mass spectrometry with ultrahigh resolution provides basic chemical information for each detected compound and also provides the opportunity to gain structural information from MS/MS experiments. The results indicate effectively separated sample fractions yielded by the chromatographic steps with tremendously decreased total numbers of compounds. Especially, argentation chromatography proved to be a valuable separation tool when it comes to heteroatom-containing constituents. In the end, the fragmentation experiments indicated high-quality data due to the clean ion isolation enabled by prior separation. The structural elucidations provided deep insights into the carbon space of crude oil.
    Keywords:  2D-chromatography; HRMS; complex mixtures; deasphalted crude oil; hyphenation; structural elucidation
    DOI:  https://doi.org/10.1021/jasms.4c00226
  7. Anal Bioanal Chem. 2024 Nov 22.
    Improved ion detection sensitivity in mass spectrometry imaging using tapping-mode scanning probe electrospray ionization to visualize localized lipids in mouse testes.
    Yoichi Otsuka, Maki Okada, Tomomi Hashidate-Yoshida, Katsuyuki Nagata, Makoto Yamada, Motohito Goto, Mengze Sun, Hideo Shindou, Michisato Toyoda.
      Mass spectrometry imaging (MSI) is a promising analytical method to visualize the distribution of lipids in biological tissues. To clarify the relationship between cellular distribution and lipid types in a tissue, it is crucial to achieve both an improvement in ion detection sensitivity and a reduction in the ionization area. We report methods for improving the efficiency of ion transfer to a mass spectrometer and miniaturizing the extraction area of a sample for tapping-mode scanning probe electrospray ionization (t-SPESI), atmospheric pressure sampling, and ionization methods. To verify the efficacy of the new t-SPESI measurement system, MSI was performed on mouse testes with a pixel size of 5 µm. Lipid images of the testes from wild-type (WT) and lysophospholipid acyltransferase 3 (LPLAT3) knockout mice revealed the characteristic distribution of docosahexaenoic acid-containing phospholipids (DHA-PLs). A comparison of the ion images obtained by MSI and optical images of the same tissues stained with hematoxylin and eosin suggested that the distribution of DHA-PLs was significantly altered by spermatogenesis in the WT mouse testes.
    Keywords:  Ambient sampling and ionization; Docosahexaenoic acid–containing phospholipids; Lipid localization; Mass spectrometry imaging; Mouse testis; Spermatogenesis
    DOI:  https://doi.org/10.1007/s00216-024-05641-x
  8. Drug Test Anal. 2024 Nov 19.
    Determination of Hormonal Growth Promotants in Beef Using Liquid Chromatography-Tandem Mass Spectrometry.
    Mary Mosburg, Yajing Li, Emily Helmes, Tara D Falt, Josephine F Trott, Gina Solomon, Russell C Hovey, Benjamin C Moeller.
      Hormonal growth promotants (HGPs) are a class of pharmaceutical agents commonly administered to cattle in the United States to improve growth rates of the animal, alter behavior, or to improve the desired characteristics of retail cuts of meat. There is a concern that low residual concentrations of HGPs may remain in tissue after slaughter, and consumption of tissues containing these compounds may increase the risk of adverse health outcomes, including cancer. Sensitive and selective methods are necessary to assess exposure of HGPs by populations that consume meat products from animals that may have been administered HGPs. A liquid chromatography-tandem mass spectrometry method was developed and validated to detect the low-level presence of HGPs including estradiol, testosterone, estradiol benzoate, melengestrol, melengestrol acetate, progesterone, testosterone propionate, trenbolone, trenbolone acetate, and α-zearalanol in retail cuts of meat following a liquid-liquid extraction using a high pH solution with 30-50× less mass of meat required as compared to similar approaches. Good chromatographic performance and sensitivity was achieved utilizing ammonium fluoride as a mobile phase additive without the need for derivatization. Validation parameters including accuracy, precision, recovery, matrix effects, limits of detection, limits of quantitation, linear range, and stability were determined. The limits of detection ranged from 0.1 to 1.0 ng/g, depending on the compound, with adequate accuracy and precision without the need for extensive sample preparation approaches.
    Keywords:  cattle; hormonal growth promotants; liquid chromatography–mass spectrometry; steroids
    DOI:  https://doi.org/10.1002/dta.3827
  9. STAR Protoc. 2024 Nov 15. pii: S2666-1667(24)00614-2. [Epub ahead of print]5(4): 103449
    Protocol for a low-volume, direct analysis urine preparation procedure for non-targeted GC-MS metabolomics.
    Bianca Allen, Laneke Luies.
      We present a low-volume, direct analysis protocol for non-targeted gas chromatography-mass spectrometry (GC-MS) metabolomics, using 100 μL of urine. The steps include sample collection, stock solution preparation, metabolite extraction, two-step derivation with a drying phase, and analysis via two-dimensional GC time-of-flight MS (GCxGC-TOFMS). This protocol improves the efficiency and thoroughness of urinary metabolite analysis, contributing to advancements in metabolomics research, disease diagnosis, and biomarker discovery. For complete details on the use and execution of this protocol, please refer to Olivier et al.1.
    Keywords:  Chemistry; Health Sciences; Mass Spectrometry; Metabolism; Metabolomics
    DOI:  https://doi.org/10.1016/j.xpro.2024.103449
  10. bioRxiv. 2024 Nov 02. pii: 2024.10.31.621412. [Epub ahead of print]
    The microbiome diversifies N -acyl lipid pools - including short-chain fatty acid-derived compounds.
    Helena Mannochio-Russo, Vincent Charron-Lamoureux, Martijn van Faassen, Santosh Lamichhane, Wilhan D Gonçalves Nunes, Victoria Deleray, Abubaker Patan, Kyle Vittali, Prajit Rajkumar, Yasin El Abiead, Haoqi Nina Zhao, Paulo Wender Portal Gomes, Ipsita Mohanty, Carlynda Lee, Aidan Sund, Meera Sharma, Yuanhao Liu, David Pattynama, Gregory T Walker, Grant J Norton, Lora Khatib, Mohammadsobhan S Andalibi, Crystal X Wang, Ronald J Ellis, David J Moore, Jennifer E Iudicello, Donald Franklin, Scott Letendre, Loryn Chin, Corinn Walker, Simone Renwick, Jasmine Zemlin, Michael J Meehan, Xinyang Song, Dennis Kasper, Zachary Burcham, Jane J Kim, Sejal Kadakia, Manuela Raffatellu, Lars Bode, Karsten Zengler, Mingxun Wang, Dionicio Siegel, Rob Knight, Pieter C Dorrestein.
      N -acyl lipids are important mediators of several biological processes including immune function and stress response. To enhance the detection of N -acyl lipids with untargeted mass spectrometry-based metabolomics, we created a reference spectral library retrieving N -acyl lipid patterns from 2,700 public datasets, identifying 851 N -acyl lipids that were detected 356,542 times. 777 are not documented in lipid structural databases, with 18% of these derived from short-chain fatty acids and found in the digestive tract and other organs. Their levels varied with diet, microbial colonization, and in people living with diabetes. We used the library to link microbial N -acyl lipids, including histamine and polyamine conjugates, to HIV status and cognitive impairment. This resource will enhance the annotation of these compounds in future studies to further the understanding of their roles in health and disease and highlight the value of large-scale untargeted metabolomics data for metabolite discovery.
    DOI:  https://doi.org/10.1101/2024.10.31.621412
  11. Mass Spectrom (Tokyo). 2024 ;13(1): A0155
    Data Processing of Product Ion Spectra: Methods to Control False Discovery Rate in Compound Search Results for Untargeted Metabolomics.
    Fumio Matsuda.
      Several database search methods have been employed in untargeted metabolomics utilizing high-resolution mass spectrometry to comprehensively annotate acquired product ion spectra. Recent technical advancements in in silico analyses have facilitated the sorting of the degree of coincidence between a query product ion spectrum, and the molecular structures in the database. However, certain search results may be false positives, necessitating a method for controlling the false discovery rate (FDR). This study proposes 4 simple methods for controlling the FDR in compound search results. Instead of preparing a decoy compound database, a decoy spectral dataset was created from the measured product-ion spectral dataset (target). Target and decoy product ion spectra were searched against an identical compound database to obtain target and decoy hits. FDR was estimated based on the number of target and decoy hits. In this study, 3 decoy generation methods, polarity switching, mirroring, and spectral sampling, were compared. Additionally, the second-rank method was examined using second-ranked hits in the target search results as decoy hits. The performances of these 4 methods were evaluated by annotating product ion spectra from the MassBank database using the SIRIUS 5 CSI:FingerID scoring method. The results indicate that the FDRs estimated using the second-rank method were the closest to the true FDR of 0.05. Using this method, a compound search was performed on 4 human metabolomic data-dependent acquisition datasets with an FDR of 0.05. The FDR-controlled compound search successfully identified several compounds not present in the Human Metabolome Database.
    Keywords:  compound search; data-dependent acquisition mode; false discovery rate; metabolomics; target–decoy method
    DOI:  https://doi.org/10.5702/massspectrometry.A0155
  12. J Chromatogr B Analyt Technol Biomed Life Sci. 2024 Nov 12. pii: S1570-0232(24)00386-6. [Epub ahead of print]1250 124377
    Development and validation of ultra-performance liquid chromatography tandem mass spectrometry methods for the quantitative analysis of the antiparasitic drug DNDI-6148 in human plasma and various mouse biomatrices.
    Wietse M Schouten, Katrien Van Bocxlaer, Hilde Rosing, Alwin D R Huitema, Jos H Beijnen, Jadel M Kratz, Charles E Mowbray, Thomas P C Dorlo.
      DNDI-6148 is a promising new oral drug for the treatment of cutaneous leishmaniasis (CL), a parasitic neglected tropical disease that affects impoverished populations worldwide. Preclinical target site pharmacokinetics (PK) studies are necessary to evaluate the actual exposure to DNDI-6148 of Leishmania parasites in the skin. To facilitate these investigations, we have developed and validated a reversed phase ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) method to quantify DNDI-6148 in relevant target site PK samples, adhering to the relevant International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) M10 guideline on bioanalytical method validation. Full validation was performed for the surrogate biomatrices human K2EDTA plasma, enzymatic digestion buffer and skin microdialysate. Partial validation was conducted for mouse K2EDTA plasma and tissues. The tissue samples, including mouse skin, liver and spleen, were homogenized using a collagenase A-based enzymatic homogenization workflow. This method was found to be 2.9-fold more effective in extracting DNDI-6148 from skin than the commonly used mechanical homogenization. Protein precipitation was subsequently carried out for all biomatrices. A surrogate biomatrix was used for each method and the range was specifically developed for its intended application, resulting in a linear concentration range of 5.00-2000 ng/mL, 2.00-1000 ng/mL, and 3.00-600 ng/mL for human K2EDTA plasma, enzymatic digestion buffer and microdialysate, respectively. Each biomatrix had intra- and inter-run accuracy and precision within 15 % for all concentration levels. Matrix effects did not affect the determination of DNDI-6148, since the stable isotopically-labelled internal standard for DNDI-6148 effectively compensated for these matrix effects. Total recovery across all methods was between 73.5 % and 81.3 % (CV ≤4.5 %). DNDI-6148 was stable under various conditions in all the tested biomatrices. However, a decrease in its concentration was observed during homogenization, for which the internal standard corrected adequately. The suitability of the method for use in future preclinical research involving DNDI-6148 was demonstrated in a preclinical target site PK study using a CL-infected murine model.
    Keywords:  DNDI-6148; Leishmaniasis; Target site pharmacokinetics; UPLC-MS/MS
    DOI:  https://doi.org/10.1016/j.jchromb.2024.124377
  13. Biomed Chromatogr. 2024 Nov 19. e6050
    A Validated Liquid Chromatography-Tandem Mass Spectrometry Method for the Determination of Methylophiopogonanone A in Rat Plasma and Its Application to Pharmacokinetic Study.
    Tiantian Xie, Yanling Hao, Yanzheng Xie.
      Methylophiopogonanone A (MOA) is one of the homoisoflavonoids isolated from Ophiopogon japonicus, which has been demonstrated to have extensive pharmacological activities. The aim of this study was to develop and validate a liquid chromatography-tandem mass spectrometry method for the measurement of MOA in rat plasma. Methylophiopogonanone B (MOB) was used as internal standard. After precipitation with acetonitrile, the samples were separated using a Waters ACQUITY HSS T3 column with 0.1% formic acid solution and acetonitrile as mobile phase. Mass detection was monitored using multiple reactions monitoring mode with precursor-to-product ion transition of m/z 343.2 > 135.1 for MOA and m/z 329.2 > 121.1 for internal standard. The assay showed good linearity over the concentration range of 1-1000 ng/mL, with correlation coefficient > 0.997. The lower limit of quantification (LLOQ) was 1 ng/mL. Acetonitrile-mediated precipitation showed high extraction efficiency (> 80%). The accuracy and precision were within the acceptable limits. MOA was demonstrated to be stable in rat plasma under the tested storage conditions. After validation, the proposed method was applied to the pharmacokinetic study of MOA in rat plasma, and the data revealed that MOA showed rapid absorption and elimination from rat plasma. The oral bioavailability of MOA in rat was 24.5%.
    Keywords:  LC‐MS/MS; Methylophiopogonanone A; bioavailability; method validation; pharmacokinetics
    DOI:  https://doi.org/10.1002/bmc.6050
  14. J Chromatogr B Analyt Technol Biomed Life Sci. 2024 Nov 14. pii: S1570-0232(24)00392-1. [Epub ahead of print]1250 124383
    Simple and rapid analytical method for the determination of methylmercury in fish and shellfish using solid-phase extraction and gas chromatography-mass spectrometry.
    Sachiko Kakimoto, Masato Yoshimitsu, Naoya Kakutani.
      Herein, we devise a method to detect methylmercury (MeHg) in fish and shellfish food samples using solid-phase extraction. We draw from the principles of the "QuEChERS" method, eliminating the need for hazardous organic solvents and employing general-purpose gas chromatography-mass spectrometry (GC-MS) equipment. The use of acetonitrile during extraction prevents emulsion formation, which could otherwise disrupt MeHg recovery. Additionally, the introduction of sulfuric acid solution during extraction dissolves sample lipids. The purification process involves solid-phase extraction instead of liquid-liquid extraction, ensuring rapid and straightforward analysis. The MeHg recovery, analyzed using reference samples and MeHg-loaded blank samples, is 86.1 %-98.3 %, and the limit of quantification is 0.02 mg/kg. The calibration curves for phenyl-derivatized MeHg exhibit exceptional linearity at 1-50 ng/mL. The intra- and inter-assay coefficients of variation validate the repeatability and intermediate precision of our method. This analytical approach is simple, and it offers high precision and accuracy, making it valuable for quantifying MeHg in fish and shellfish food samples.
    Keywords:  Fish; GC–MS; Methylmercury; Phenyl derivatization; Shellfish; Solid-phase extraction; “QuEChERS” method
    DOI:  https://doi.org/10.1016/j.jchromb.2024.124383
  15. Phytochem Rev. 2024 ;23(5): 1415-1442
    Advanced high-resolution chromatographic strategies for efficient isolation of natural products from complex biological matrices: from metabolite profiling to pure chemical entities.
    Emerson Ferreira Queiroz, Davy Guillarme, Jean-Luc Wolfender.
      The isolation of pure compounds from extracts represents a key step common to all investigations of natural product (NP) research. Isolation methods have gone through a remarkable evolution. Current approaches combine powerful metabolite profiling methods for compounds annotation with omics mining results and/or bioassay for bioactive NPs/biomarkers priorisation. Targeted isolation of prioritized NPs is performed using high-resolution chromatographic methods that closely match those used for analytical profiling. Considerable progress has been made by the introduction of innovative stationary phases providing remarkable selectivity for efficient NPs isolation. Today, efficient separation conditions determined at the analytical scale using high- or ultra-high-performance liquid chromatography can be optimized via HPLC modelling software and efficiently transferred to the semi-preparative scale by chromatographic calculation. This ensures similar selectivity at both the analytical and preparative scales and provides a precise separation prediction. High-resolution conditions at the preparative scale can notably be granted using optimized sample preparation and dry load sample introduction. Monitoring by ultraviolet, mass spectrometry, and or universal systems such as evaporative light scattering detectors and nuclear magnetic resonance allows to precisely guide the isolation or trigger the collection of specific NPs with different structural scaffolds. Such approaches can be applied at different scales depending on the amounts of NPs to be isolated. This review will showcase recent research to highlight both the potential and constraints of using these cutting-edge technologies for the isolation of plant and microorganism metabolites. Several strategies involving their application will be examined and critically discussed.
    Graphical abstract:
    Keywords:  Biomarker identification; Chromatographic calculation; Gradient transfer; Isolation; Metabolomics; Multi-detection; Natural products; Semi-preparative HPLC; UHPLC-PDA-ESI-HRMS
    DOI:  https://doi.org/10.1007/s11101-024-09928-w
  16. Anal Chem. 2024 Nov 22.
    Predicting Tandem Mass Spectra of Small Molecules Using Graph Embedding of Precursor-Product Ion Pair Graph.
    Fujian Zheng, Lei You, Xinjie Zhao, Xin Lu, Guowang Xu.
      Liquid chromatography-mass spectrometry (LC-MS)-based metabolomics identification relies heavily on high-quality MS/MS data; MS/MS prediction is a good way to address this issue. However, the accuracy of the prediction, resolution, and correlation with chemical structures have not been well-solved. In this study, we have developed a MS/MS prediction method, PPGB-MS2, which transforms the MS/MS prediction into fragment intensity prediction, and the concept of precursor-product ion pair graph bags (PPGBs) was introduced to represent fragments, achieving uniform representation of precursor and product ion structures and MS/MS fragmentation information. The chemical structure information is kept before it is incorporated into machine learning models. Due to the PPGB representation, graph neural networks (GNNs) can be utilized to achieve MS/MS fragment intensity prediction. The system was trained and evaluated using [M+H]+ and [M-H]- data acquired by an Agilent QTOF 6530 in the NIST 20 tandem MS database. Results demonstrated that the average cosine similarity is 0.71 in the test set, which is higher than classical MS/MS prediction methods. PPGB-MS2 also achieves high-resolution MS/MS prediction due to its effective management of the correspondence between fragments and structures.
    DOI:  https://doi.org/10.1021/acs.analchem.4c04375
  17. Clin Chim Acta. 2024 Nov 16. pii: S0009-8981(24)02308-8. [Epub ahead of print]566 120055
    Cortisol quantification in human plasma and urine by liquid chromatography coupled to mass spectrometry: Validation, analysis and application in a reference population and patients with adrenal incidentalomas.
    Andressa Cristina Dos Santos Marques, Bruna Brito, Jéssica Gorett Brito Fontes, Gabriel Reis Alves Carneiro, João Felipe Dickson Rebelo, Aline Barbosa Moraes, Leonardo Vieira Neto, Monica Costa Padilha.
      Cortisol is a glucocorticoid hormone, which is involved in cardiovascular, metabolic, inflammatory and behavioral processes in the human body. Immunoassays, used for routine analysis of analytes, usually lead to erroneous quantification due to the low specificity of these methods. In this study, we developed LC-MS/MS methods with surrogating matrices for evaluating cortisol in both urine and plasma samples and validated them according to Brazilian Health Regulatory Agency guidelines. Urine samples were prepared with an enzymatic hydrolysis stage, followed by a solid-phase extraction (C18 cartridges) using dichloromethane:methanol 9:1 as elution solvent. Plasma samples were prepared by protein precipitation with acetonitrile, using 50 μL of sample. HPLC was performed using a C8 column under 300 mL min-1 flow gradient conditions with water and methanol, both containing 5 mM ammonium formate and 0.1 % formic acid. Mass spectrometer with electrospray ionization in positive mode and selected reaction monitoring as detection technique were employed. Calibration curves were linear over a concentration range of 1-200 ng mL-1 for urine (r2 = 0.9950) and 0.5-300 ng mL-1 for plasma (r2 = 0.9970). The methods were selective, showed suitable precision, accuracy, and sensibility (limit of quantification = 0.85 ng mL-1 for urine and 0.15 ng mL-1 for plasma). Validated methods were successful applied to 22 real samples and a cohort of patients [n = 63 urines and n = 79 plasmas (from the Clementino Fraga Filho University Hospital, Rio de Janeiro, Brazil)].
    Keywords:  Chromatography in diagnosis; HPLC-MS/MS; MACS; Plasma cortisol; Urinary cortisol
    DOI:  https://doi.org/10.1016/j.cca.2024.120055
  18. Anal Methods. 2024 Nov 19.
    EigenRF: an improved metabolomics normalization method with scores for reproducibility evaluation on importance rankings of differential metabolites.
    Chencheng Tang, Dongfang Huang, Xudong Xing, Hua Yang.
      Screening differential metabolites is of great significance in biomarker discovery in metabolomics research. However, it is susceptible to unwanted variations introduced during experiments. Previous normalization methods have improved the accuracy of inter-group classification by eliminating systematic errors. Nonetheless, the classification ability of differential metabolites obtained through these methods still requires further enhancement, and the reproducibility evaluation on importance rankings of differential metabolites is often disregarded. The EigenRF algorithm was developed as an improvement over the previous metabolomics normalization method referred to as EigenMS, which aims to normalize metabolomics data. Furthermore, scoring metrics, including the local consistency (LC) and overall difference (OD) scores, were introduced to evaluate the reproducibility of importance rankings of differential metabolites from a dual perspective. After conducting validation on three publicly accessible datasets, the EigenRF method has demonstrated enhanced classification ability of differential metabolites as well as improved reproducibility. In summary, EigenRF enhances the reliability of differential metabolites in metabolomics research, benefiting the further exploration of molecular mechanisms underlying biological alterations in complex matrices. The EigenRF algorithm was implemented in an R package: https://www.github.com/YangHuaLab/EigenRF.
    DOI:  https://doi.org/10.1039/d4ay01569j
  19. J Lipid Res. 2024 Nov 18. pii: S0022-2275(24)00203-7. [Epub ahead of print] 100698
    A Sterol Panel for Rare Lipid Disorders: Sitosterolemia, Cerebrotendinous Xanthomatosis and Smith-Lemli-Opitz Syndrome.
    Alexander Bauer Westbye, Lili L Dizdarevic, Sandra R Dahl, Emil Andreas Asprusten, Yngve Thomas Bliksrud, Anita Lövgren Sandblom, Ulf Diczfalusy, Per M Thorsby, Kjetil Retterstøl.
       BACKGROUND: Disease-specific sterols accumulate in the blood of patients with several rare lipid disorders. Biochemical measurement of these sterols is important for correct diagnosis and sometimes monitoring of treatment. Existing methods to measure sterols in blood, particularly plant sterols, are often laborious and time consuming. Partly as a result, clinical access to sterol measurements is limited in many parts of the world.
    METHODS: A simple and rapid method to extract free sterols from human serum and quantitate their concentration using isotope-dilution liquid chromatography tandem mass spectrometry (LC-MS/MS) without derivatization was developed. The method was designed to be "compatible" with routine workflows (e.g. 96-well format) in a clinical lab and extensively validated. Serum from at least 125 controls were analyzed and used to estimate the upper reference limits for sitosterol, campesterol, stigmasterol, desmosterol, 7-dehydrocholesterol (7DHC), lathosterol and cholestanol. Serum from patients with the rare lipid disorders sitosterolemia (n=7), Smith-Lemli-Optiz syndrome (SLOS; n=1) and cerebrotendinous xanthomatosis (CTX; n=1) were analyzed.
    RESULTS: All seven sitosterolemia patients had greatly elevated levels of free plant sterols (sitosterol, campesterol and stigmasterol) compared to the controls. The SLOS serum contained massively increased concentrations of 7DHC. CTX serum contained greatly increased concentrations of cholestanol, as well as 7DHC and lathosterol. Spiking experiments indicated that the method is likely also useful for the diagnosis of desmosterolosis and lathosterolosis.
    CONCLUSION: The reported method is a relatively simple and fast LC-MS/MS method capable of quantitating diagnostically important sterols and differentiated patients with three rare lipid disorders from controls.
    Keywords:  7-dehydrocholesterol; 7DHC; CTX; LC-MS/MS; SLOS; Smith-Lemli-Opitz Syndrome; campesterol; cerebrotendinous xanthomatosis; cholestanol; sitosterol; sitosterolemia; sterol; stigmasterol
    DOI:  https://doi.org/10.1016/j.jlr.2024.100698
  20. Mass Spectrom Rev. 2024 Nov 18.
    Postionization Mass Spectrometry Imaging: Past, Present, and Future.
    Xiaokang Guan, Qiao Lu, Shuxian Liu, Xiaowen Yan.
      Mass spectrometry imaging (MSI) technologies are widely used today to study the in situ spatial distributions for a variety of analytes. As these technologies advance, the pursuit of higher resolution in MSI has intensified. The limitation of direct desorption/ionization is its insufficient ionization, posing a constraint on the advancement of high-resolution MSI technologies. The introduction of postionization process compensates the low ionization efficiency caused by sacrificing the desorption area while pursuing high spatial resolution, resolving the conflict between high spatial resolution and high sensitivity in direct desorption/ionization method. Here, we discuss the sampling and ionization steps of MSI separately, and review the postionization methods in MSI according to three different sampling modes: laser sampling, probe sampling, and ion beam sampling. Postionization technology excels in enhancing ionization efficiency, boosting sensitivity, mitigating discrimination effect, simplifying sample preparation, and expanding the scope of applicability. These advantages position postionization technology as a promising tool for biomedical sciences, materials sciences, forensic analysis and other fields.
    Keywords:  imaging; mass spectrometry; postionization; review; sampling modalities
    DOI:  https://doi.org/10.1002/mas.21918
  21. J Phys Chem A. 2024 Nov 20.
    Application of UHPLC-ESI-MS/MS to Identify Free Radicals via Spin Trapping with BMPO.
    Lena Gerritz, Véronique Perraud, Kathryn M Weber, Manabu Shiraiwa, Sergey A Nizkorodov.
      Free radicals play an important role in many chemical and biological processes, but due to their highly reactive and short-lived nature, they evade most analytical techniques, limiting our understanding of their formation and reactivity. Spin trapping molecules can react with free radicals to form radical adducts with lifetimes long enough for analysis. Mass spectrometry is an attractive way to identify radical adducts, but due to their radical nature, they form untraditional oxidized [M]+ and reduced [M+2H]+ ions, which complicates the interpretation of mass spectrometry analysis. This work uses simplified mixtures of radicals generated in both water and dimethyl sulfoxide (DMSO) with spin trap 5-tert-butoxycarbonyl-5-methyl-1-pyrroline-N-oxide (BMPO), to elucidate the behavior of nitroxide spin traps in electrospray ionization (ESI) mass spectrometry (MS) interfaced with liquid chromatography (LC). This study proposes a disproportionation mechanism to explain the formation of the oxidized and reduced BMPO adducts detected by LC-ESI-MS and explores the formation of "di-adducts" through radical recombination. We finally present a framework for differentiating between the different types of ions using collision induced fragmentation mass spectra (MS/MS). This work offers a comprehensive investigation into the behavior of radical adducts in ESI-MS to streamline the identification of organic radicals and advance understanding of radical chemistry.
    DOI:  https://doi.org/10.1021/acs.jpca.4c05311
  22. Harmful Algae. 2024 Nov;pii: S1568-9883(24)00172-0. [Epub ahead of print]139 102739
    Identification of novel microcystins in algal extracts by a liquid chromatography-high-resolution mass spectrometry data analysis pipeline.
    Kirsten A Cottrill, Christopher O Miles, Logan C Krajewski, Brady R Cunningham, William Bragg, Noelani R Boise, Kristin D Victry, David S Wunschel, Karen L Wahl, Elizabeth I Hamelin.
       BACKGROUND: Microcystins are an emergent public health problem. These toxins are secondary metabolites of harmful cyanobacterial blooms, with blooms becoming more prevalent with eutrophication of water. Exposure to microcystins can result in sickness, liver damage, and even death. Over 300 microcystins have been identified to date, with differences in toxicity based on the specific amino acid composition. Because of this diversity in microcystins, as well as the likelihood of detecting as yet undiscovered microcystins, it is vital to establish a methodological workflow to identify any microcystin in a complex sample, regardless of the availability of a reference standard. Additionally, ascribing varying levels of confidence to these identifications is critical to effectively communicate discoveries.
    METHODS: A liquid-chromatography-high-resolution mass spectrometry method was utilized to identify microcystins present in cyanobacterial extracts from a strain of Microcystis aeruginosa and an Aphanizomenon sp. First, microcystin congeners with available standards were identified in the cyanobacterial extract. These known-unknown microcystins were considered to have the highest confidence identifications due to availability of accurate masses, retention times, and library spectra for comparison. Utilizing the spectra of these microcystins, relatively high-abundance diagnostic product-ions were identified and employed to screen the data for additional candidate microcystins. Microcystins without a standard that had an exact mass matching a microcystin published in CyanoMetDB were considered semi-known-unknown microcystins. The remaining microcystins were considered unknown-unknown microcystins. The identities of the microcystins determined herein were additionally supported by product-ion analysis, thiol reactivity, esterification reactions, neutral loss analysis, and literature contextualization.
    RESULTS: In total, utilizing the systematic workflow presented herein, 23 microcystins were identified in the M. aeruginosa culture, including two not published previously: [d-Asp3]MC-LCit and the incompletely identified MC-L(C7H11NO3).
    Keywords:  Aphanizomenon sp.; High-resolution mass spectrometry; Microcystin; Microcystis aeruginosa; Reverse-phase chromatography
    DOI:  https://doi.org/10.1016/j.hal.2024.102739
  23. J Chromatogr B Analyt Technol Biomed Life Sci. 2024 Nov 13. pii: S1570-0232(24)00384-2. [Epub ahead of print]1248 124375
    Determination of furmonertinib in human plasma and cerebrospinal fluid by UPLC-MS/MS: Application in lung cancer patients with and without brain metastasis.
    Hongxin Qie, Cong Song, Yuxiang Xu, Haopeng Zhao, Wenlin Gong, Peiyuan Wang, Xiaonan Gao, Jinglin Gao, Zhangying Feng, Mingxia Wang.
      Furmonertinib (AST2818) is a selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) being developed for the treatment of patients with EGFR mutation-positive non-small cell lung cancer. Quantification of furmonertinib in plasma and cerebrospinal fluid (CSF) can be used to assess penetration of furmonertinib into the central nervous system (CNS). This paper described ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) methods for quantification of furmonertinib in human plasma and CSF. Sample separation was achieved on a Kinetex C18 column (100 mm × 2.1 mm, 2.6 μm) after simple protein precipitation with acetonitrile. The mobile phase was composed of acetonitrile and 5 mM ammonium acetate with 0.2 % formic acid in water. Quantitative ion pairs were m/z 569.3 → 72.2 for furmonertinib and m/z 526.5 → 72.2 for aumolertinib, which was used as the internal standard (IS). The calibration curves showed good linearity (r2 > 0.99) over concentration range of 0.5-200 ng/mL(plasma sample) and 0.05-30 ng/mL(CSF sample). The precision (RSD) was ≤7.86 %, and the accuracy fell within the range of 96.2 %-109.3 %, all meeting acceptance criteria. The matrix effect was from 94.3 % to 102.1 %. The recovery of analytes fell within the range of 93.3 %-98.9 %. The established analytical methods showed great sensitivity, simplicity, accuracy and reliability for the analysis of furmonertinib in human plasma and CSF. This assay would be helpful to predict the effectiveness and toxicities of furmonertinib in the pursuit of precision medicine for lung cancer patients.
    Keywords:  CNS metastasis; Cerebrospinal Fluid; Furmonertinib; Lung Cancer; Plasma; UPLC-MS/MS
    DOI:  https://doi.org/10.1016/j.jchromb.2024.124375
  24. Analyst. 2024 Nov 22.
    Visualizing active fungicide formulation mobility in tomato leaves with desorption electrospray ionisation mass spectrometry imaging.
    Akhila Ajith, Emrys Jones, Emily Prince, Drupad K Trivedi, Giles N Johnson, Phillip J Milnes, Nicholas P Lockyer.
      Newer and safer agrochemicals are always in demand to meet the increasing needs of a growing population for affordable food. Spatial chemical monitoring of the active mobility of an agrochemical is essential to this agrochemical development process and mass spectrometry imaging (MSI) is proposed as a safer, easier alternative to the existing standard of autoradiography for the same. With desorption electrospray ionisation mass spectrometry imaging (DESI MSI) using leaf imprints, we were able to visualize the active agrochemical mobility of a commercial fungicide formulation with the active ingredient Azoxystrobin in whole tomato leaves. The leaf-imprinting method was optimized with precise control over the pressure conditions and time of imprinting to yield highly consistent samples for imaging. The reproducibility of this method was tested with the Azoxystrobin formulation applied to tomato leaves and was compared to the mobility of the unformulated Azoxystrobin standard in similar application conditions. The xylem mobility and the lateral-leaf lamina spreading of the fungicide were visualized with mass spectrometry imaging and validated using complementary LC-MS studies. The necessity and importance of the agrochemical application as a formulation were re-iterated by the limited mobility observed in Azoxystrobin standard studies compared to the Azoxystrobin formulation. This mass spectrometry imprint-imaging method could be translated for the visualization of any xenobiotic in further foliar systems particularly with soft leaves.
    DOI:  https://doi.org/10.1039/d4an01309c
  25. J Org Chem. 2024 Nov 22.
    A Tool for Reaction Monitoring in Real Time, the Development of a "Walk-Up Automated Reaction Profiling" System.
    Muhammad Alimuddin, Louise Bernier, John F Braganza, Michael R Collins, Martha Ornelas, Paul F Richardson, Neal Sach, Deszra Shariff, Wei Wang, Alex Yanovsky.
      Optimization of chemical reactions requires a thorough analysis of reaction products and intermediates over a given time course. Chemical reactions are often analyzed by liquid chromatography-mass spectrometry (LC-MS), but generating LC-MS samples and data analysis is time-consuming and produces a significant amount of waste. We sought to remove the sample preparation and data analysis steps by implementing an iChemExplorer/Agilent LC-MS instrument as our reactor and analysis tool, coupled with an automated report generator of reaction progress over time. Herein, we show that our easy-to-use walk-up automated reaction profiling (WARP) system can sample chemical reactions multiple times to produce a data-rich report of reaction progress over time.
    DOI:  https://doi.org/10.1021/acs.joc.4c02027
  26. PLoS One. 2024 ;19(11): e0313044
    Identification and quantification of the molecular species of bilirubin BDG, BMG and UCB by LC‒MS/MS in hyperbilirubinemic human serum.
    Stephany M Castillo-Castañeda, Liliana Rivera-Espinosa, Josefina Gómez-Garduño, Jacqueline Cordova-Gallardo, Juan Luis Chávez-Pacheco, Nahum Méndez-Sánchez.
       BACKGROUND AND AIMS: Unconjugated bilirubin (UCB) is a byproduct of the heme group that indicates irregularities in the metabolism of several important biological molecules, such as hemoglobin. UCB is processed by hepatic UGT1A1, which catalyzes its conjugation to the metabolites bilirubin diglucuronide (BDG) and bilirubin monoglucuronide (BMG). The serum concentrations of BDG and BMG may indicate liver injury or dysfunction. The aim of this study was to standardize and validate a method for the identification and simultaneous quantification of BMG, BDG and UCB by LC‒MS/MS.
    METHODS: Liquid‒liquid extraction allows the separation of UCB, BMG and BDG from the serum of healthy subjects or patients with liver injury. Detection and quantification were performed using an LC‒MS/MS method. Compound separation was achieved with a BEH-C18 column at 40°C. The mobile phase was prepared with 5 mM ammonium acetate (pH 6) and acetonitrile, and a flow gradient was applied.
    RESULTS: This is the first study to directly quantify BMG and UCB levels in human serum; no postcalculations or correction factors are needed. However, BDG quantification requires calculations and a correction factor. We identified the molecular species with ionic transitions m/z1+ 585.4 > 299.2 for UCB, 761.3 > 475.3 for BMG, 937.3 > 299.5 for BDG and mesobilirubin 589.4 > 301.3 (IS).
    CONCLUSION: The procedures used in this study allowed the simultaneous identification and quantification of the molecular species of bilirubin, BDG, BMG and UCB. Analysis of the serum levels in patients with hyperbilirubinemia revealed that patients with acute-on-chronic liver failure had elevated levels of these species.
    DOI:  https://doi.org/10.1371/journal.pone.0313044
  27. J Chromatogr B Analyt Technol Biomed Life Sci. 2024 Nov 07. pii: S1570-0232(24)00364-7. [Epub ahead of print]1248 124355
    Evaluation of the ionization efficiency in phosphatidylcholine positional isomers with docosahexaenoic acid bound to the sn-1 or sn-2 position.
    Kana Fujiwara, Seiya Tanaka, Koyama Tomoyuki, Kazuaki Yoshinaga, Naohiro Gotoh.
      Phosphatidylcholine (PC), a key phospholipid, contains 2 fatty acids that can be bound at the sn-1 and sn-2 positions, resulting in positional isomers when different fatty acids are attached. Currently, there is no established method for identifying phospholipid molecular species and quantifying individual isomers using authentic standards of each PC isomer. In this study, we prepare authentic analytical standards for PC positional isomers through chemical synthesis and preparative purification. These isomers contain docosahexaenoic acid (DHA, 22:6) and palmitic acid (16:0) attached at the sn-1 and sn-2 positions and are denoted as PC(22:6/16:0) and PC(16:0/22:6), respectively. Standard solutions of PC(22:6/16:0) and PC(16:0/22:6) were analyzed using liquid chromatography-tandem mass spectrometry, and calibration curves of the PC positional isomers were generated to compare their ionization efficiencies. The ionization efficiency of PC(22:6/16:0) was 2.32 times higher than that of PC(16:0/22:6), indicating that the ionization efficiency depends on the binding position of the fatty acid. Elucidating and correcting the differences in the ionization efficiencies of the PC positional isomers will enable the accurate quantitative analysis of lipidomes in the future.
    Keywords:  Docosahexaenoic acid; Ionization efficiency; LC-MS/MS; Phosphatidylcholine; Positional isomer; quantitative NMR
    DOI:  https://doi.org/10.1016/j.jchromb.2024.124355
  28. Anal Chem. 2024 Nov 19.
    PyINETA: Open-Source Platform for INADEQUATE-JRES Integration in NMR Metabolomics.
    Rahil Taujale, Mario Uchimiya, Chaevien S Clendinen, Ricardo M Borges, Christoph W Turck, Arthur S Edison.
      Robust annotation of compounds is a critical element in metabolomics. The 13C-detection NMR experiment incredible natural abundance double-quantum transfer experiment (INADEQUATE) stands out as a powerful tool for structural elucidation, but this valuable experiment is not often included in metabolomics studies. This is partly due to the lack of a community platform that provides structural information based on INADEQUATE. Also, it is often the case that a single study uses various NMR experiments synergistically to improve the quality of information or balance total NMR experiment time, but there is no public platform that can integrate the outputs of INADEQUATE with other NMR experiments. Here, we introduce PyINETA, a Python-based INADEQUATE network analysis. PyINETA is an open-source platform that provides structural information on molecules using INADEQUATE, conducts database searches using an INADEQUATE library, and integrates information on INADEQUATE and a complementary NMR experiment 13C J-resolved experiment (13C-JRES). 13C-JRES was chosen because of its ability to efficiently provide relative quantification in a study of the 13C-enriched samples. Those steps are carried out automatically, and PyINETA keeps track of all the pipeline parameters and outputs, ensuring the transparency of annotation in metabolomics. Our evaluation of PyINETA using a model mouse study showed that PyINETA successfully integrated INADEQUATE and 13C-JRES. The results showed that 13C-labeled amino acids that were fed to mice were transferred to different tissues and were transformed to other metabolites. The distribution of those compounds was tissue-specific, showing enrichment of specific metabolites in the liver, spleen, pancreas, muscle, or lung. PyINETA is freely available on NMRbox.
    DOI:  https://doi.org/10.1021/acs.analchem.4c03966
  29. ArXiv. 2024 Oct 30. pii: arXiv:2410.23326v1. [Epub ahead of print]
    MassSpecGym: A benchmark for the discovery and identification of molecules.
    Roman Bushuiev, Anton Bushuiev, Niek F de Jonge, Adamo Young, Fleming Kretschmer, Raman Samusevich, Janne Heirman, Fei Wang, Luke Zhang, Kai Dührkop, Marcus Ludwig, Nils A Haupt, Apurva Kalia, Corinna Brungs, Robin Schmid, Russell Greiner, Bo Wang, David S Wishart, Li-Ping Liu, Juho Rousu, Wout Bittremieux, Hannes Rost, Tytus D Mak, Soha Hassoun, Florian Huber, Justin J J van der Hooft, Michael A Stravs, Sebastian Böcker, Josef Sivic, Tomáš Pluskal.
      The discovery and identification of molecules in biological and environmental samples is crucial for advancing biomedical and chemical sciences. Tandem mass spectrometry (MS/MS) is the leading technique for high-throughput elucidation of molecular structures. However, decoding a molecular structure from its mass spectrum is exceptionally challenging, even when performed by human experts. As a result, the vast majority of acquired MS/MS spectra remain uninterpreted, thereby limiting our understanding of the underlying (bio)chemical processes. Despite decades of progress in machine learning applications for predicting molecular structures from MS/MS spectra, the development of new methods is severely hindered by the lack of standard datasets and evaluation protocols. To address this problem, we propose MassSpecGym -- the first comprehensive benchmark for the discovery and identification of molecules from MS/MS data. Our benchmark comprises the largest publicly available collection of high-quality labeled MS/MS spectra and defines three MS/MS annotation challenges: \textit{de novo} molecular structure generation, molecule retrieval, and spectrum simulation. It includes new evaluation metrics and a generalization-demanding data split, therefore standardizing the MS/MS annotation tasks and rendering the problem accessible to the broad machine learning community. MassSpecGym is publicly available at \url{https://github.com/pluskal-lab/MassSpecGym}.
  30. Anal Chem. 2024 Nov 18.
    Discovery of Acylated Glycine and Alanine by Integrating Chemical Derivatization-Based LC-MS/MS and Knowledge-Driven Prediction.
    Qinwen Xiao, Meiyu Gao, Jiarui Sun, Yuan Tian, Zunjian Zhang, Pei Zhang, Fengguo Xu.
      Acylated amino acids (acyl-AAs), which consist of an amino acid head and an organic acid tail, play vital roles in various biological processes. Glycine (Gly) is the most common substrate for acylation with the organic acid tails exhibiting considerable diversity. Alanine (Ala) also exists in multiple acylated forms, predominantly modified by long-chain fatty acids. However, the full scope of acylated Gly and Ala remains largely unexplored. In this study, we employed a knowledge-driven prediction approach to expand the spectrum of acylated Gly and Ala by incorporating 111 organic acids from five different classes as potential acyl donors, leading to the generation of 222 acylated Gly and Ala species. To enhance mass spectrometry (MS) response, we used a chemical derivatization-based LC-MS/MS approach, employing dimethylamino-naphthalene-1-sulfonyl piperazine (Dns-PP) and its stable isotope-labeled form (d6-Dns-PP) as labeling reagents. Moreover, in-source fragmentation (ISF) was utilized to increase the fragment diversity and utility, aiding in structure elucidation. This strategy resulted in the identification of 53 acylated Gly and Ala metabolites in rat biological matrices, including 17 novel metabolites with distinct tissue-specific distributions. Our approach offers a deeper understanding of the physiological and pathological roles of acylated Gly and Ala, while also opening avenues for the discovery of other modified metabolites.
    DOI:  https://doi.org/10.1021/acs.analchem.4c03145
  31. J Chromatogr A. 2024 Oct 28. pii: S0021-9673(24)00850-1. [Epub ahead of print]1739 465476
    Development of deep learning software to improve HPLC and GC predictions using a new crown-ether based mesogenic stationary phase and beyond.
    Warda Fella Belaid, Azeddine Dekhira, Philippe Lesot, Ouassila Ferroukhi.
      The application of AI to analytical and separative sciences is a recent challenge that offers new perspectives in terms of data prediction. In this work, we report an AI-based software, named Chrompredict 1.0, which based on chromatographic data of a novel mesogenic crown ether stationary phase (CESP). Its molecular design represents a significant advancement due to the unique combination of properties and binding capabilities, including the formation of a cavity, mesogenic behavior via mobile chains, and a range of polar and non-polar interactions (aromatic rings, N=N and C=O double bonds, alkyl chains, π-π interactions, and hydrogen bonding). The mesogenic phase is effective in both normal and reversed-phase chromatography, enhancing the software's adaptability across diverse datasets. Here we introduce for the first time an unprecedented scientific approach, integrating deep learning techniques with the novel CESP, which demonstrates exceptional thermal and analytical performance in both liquid chromatography modes, especially in the separation of complex hydrocarbon isomers. This ability enables the results obtained with CESP to extend across various types of stationary phases. Leveraging these insights, a comprehensive chromatographic dataset on a series of aromatic and polyaromatic molecules interacting with our CESP was used to train a Deep Learning Model (DLM). This model is embedded within a user-friendly software, Chrompredict 1.0, designed for predicting chromatographic parameters (MAE = 0.042, R² = 0.95) by selecting chemical descriptors directly from SMILES notation. It offers a deeper understanding of molecular structure and interactions through exploratory data analysis, identifying key factors affecting model accuracy and chromatographic behavior. Users can configure hyperparameters, choose from six machine learning models, and compare their performance with DLM. Chrompredict 1.0 excels in retention behavior prediction for compounds with known structures, and it accurately predicts chromatographic retention and thermal characteristics for different temperatures in HPLC and GC. The model has been successfully tested with METLIN database of 1,023 small molecules of diverse structures and polarities (R² > 0.75, error range ±7.8 s). Overall, the CESP, combined with Chrompredict 1.0, offers a robust tool for intelligent chromatographic analysis, encompassing chemo-informatics, statistical analysis, and graphical capabilities across a broad range of compounds and stationary phases.
    Keywords:  Crown ether; Deep learning software; Liquid and gas chromatography; Mesogenic stationary phase; Retention time prediction
    DOI:  https://doi.org/10.1016/j.chroma.2024.465476
  32. PLoS One. 2024 ;19(11): e0313924
    Analysis of inorganic arsenic and methylarsenic in soil after derivatization by gas chromatography-mass spectrometry.
    Wenzhi Zhao, Yuan Yang, Jintao Zhang, Tao Liu.
      Gas chromatography-mass spectrometry (GC-MS) has been applied to the analysis of arsenic forms in water, plants, and other samples; however, it has not been used to determine the form of arsenic in soil due to the complex soil matrix. The purpose of this study was to develop an analytical method for the simultaneous determination of inorganic arsenic species (As (III) and As (V)) and monomethylarsonic acid (MMA) in soil using GC-MS. The arsenic compounds were subjected to derivatization with 2,3-dimercapto-1-propanol (BAL) and subsequently analyzed using GC-MS. The BAL volume, derivatization reaction time, and temperature were optimized using standard added soil extracts. A reaction with 150 μL of BAL at 40°C for 30 min was selected as the optimal condition for quantitative derivatization of both inorganic arsenic (iAs) and MMA. The calibration curves exhibited linearity within the range of 5-100 ng/mL for each arsenic species, with correlation coefficients exceeding 0.997. The limits of detection for each arsenic species were determined to be 0.24 ng/mL and 1.31 ng/mL, respectively. The accuracy of the method was verified by the recovery of reference samples. The recovery experiments for reference samples showed that the recovery rates for As (III), As (V), and MMA were 89.5-93.7%, 88.5-105.6%, and 90.2-95.8% respectively, with precision ranging from 4.6 to 6.5%, 2.3 to 3.8%, and 2.4 to 6.3%. These results indicate good accuracy and precision. The accuracy of this method is not significantly different from that of liquid chromatography-inductively coupled plasma mass spectrometry (p = 0.05). The optimized method was sensitive, convenient and reliable for the extraction and analysis of different arsenic species in soil samples.
    DOI:  https://doi.org/10.1371/journal.pone.0313924
  33. J Chromatogr B Analyt Technol Biomed Life Sci. 2024 Nov 09. pii: S1570-0232(24)00359-3. [Epub ahead of print]1249 124350
    Green RP-HPLC method for the estimation of carfilzomib in bulk, protein nanocarriers and human plasma: Application of chemometrics and Monte-Carlo simulations.
    Drishti Panjwani, Asha Patel, Deepak Mishra, Shruti Patel, Viral Patel, Mange Ram Yadav, Bhupinder Singh.
      Carfilzomib is a tetrapeptide epoxyketone that has shown potential clinical outcomes in the treatment of multiple myeloma. However, inaccuracies in quantifying such peptide drug products have arisen due to poor stability, low solubility, time-consuming techniques, complex physicochemical properties, and use of non-green solvents with less recyclability. This provides a substantial urge to develop an ecological and sensitive analytical method for quantifying peptide drugs from matrix formulation and biological samples in early as well as lateral stages of product development in pharma industries. As a result, the study aimed to develop a robust ecological method for estimation of carfilzomib via Green RP-HPLC using analytical quality by design (AQbD) paradigms with specific application in protein nanoparticles and biological matrix. Initially, an appropriate wavelength for quantification of carfilzomib was chosen using principal component analysis (PCA) as a chemometric tool.Risk assessment followed by factor screening studies using 8-factor Placket-Burman Design aided in earmarking critical method parameters (CMPs) affecting critical analytical attributes (CAAs). Further, Central Composite Design (CCD) was employed for design space optimisation to demarcate optimum chromatographic conditions, which were corroborated for robustness using Monte-Carlo simulations. The method was validated as per ICH Q2 (R2), followed by quantifying the greenness of the method using Green Assessment tools. The method optimisation resulted in the optimal chromatographic conditions using Green RP-HPLC. The chromatographic system was equipped with a Phenomenex Aeris Peptide-XC C18 column (150 × 4.6 mm × 5 µm), and the mobile phase was composed of isopropanol:methanol:0.1 M PBS (pH 5.5 adjusted using 0.1 % formic acid) (35:45:20v/v), with a 1 ml/min flow rate at a 210 nm ʎmax. The optimised chromatographic conditions resulted in a short retention time (RT) of 4.95 mins, 0.87 tailing factor (TF), 4,875,122 peak area (PA), and 8995 theoretical plate count (TPC). The method demonstrated linearity in a wide range of concentrations (0.1-20 µg/ml) with a correlational coefficient of 0.997 and < 2 % RSD. The method unearthed a high precision rate with more than 95 % of drug recovery in protein nanoparticles and human plasma, thereby confirming the accuracy and sensitivity of the developed method. Chemometrics and Monte-Carlo simulations ratified the robustness and sensitivity of the developed analytical method of Carfilzomib with established greenness and a high degree of practical utility in protein-based nano formulations and human plasma matrix for life cycle product development.
    Keywords:  Bioanalytical method; Central-composite-design; Liquid chromatography; Monte-Carlo Simulations; Principal component analysis; Protein-peptide analysis
    DOI:  https://doi.org/10.1016/j.jchromb.2024.124350
  34. J Chromatogr A. 2024 Nov 14. pii: S0021-9673(24)00895-1. [Epub ahead of print]1739 465521
    Evaluation of various mass spectrometry mode based on gas chromatography for quantifying the polycyclic aromatic hydrocarbon metabolites in human urine.
    Shan Bao, Jiankun Qian, Tian Qiu, Weilong Jiang, Wen Gu, Yingli Qu, Xue Bai, Xiaohong Yu, Yuchen Jiang, Song Tang, Yuebin Lv, Xiaoming Shi, Yifu Lu.
      Hydroxyl polycyclic aromatic hydrocarbons (OH-PAHs) are frequently used as biomarkers to assess human exposure to polycyclic aromatic hydrocarbons (PAHs), which are typically present in minute concentrations in the human body. Although several studies have outlined methods for measuring OH-PAHs in human urine, these approaches may have limitations concerning the range of compounds detected, the sample volume required for pre-treatment, accuracy, and instrument maintenance costs. Advances in mass spectrometry technology have facilitated the use of various mass spectrometry modes based on gas chromatography. It is essential to evaluate different mass spectrometry modes to identify a more reliable and practical method for quantifying OH-PAHs in urine. Our comparative analysis of three gas chromatography-mass spectrometry modes revealed that advanced electron ionization (AEI) mode exhibited greater sensitivity for determination compared to electron ionization (EI) mode in tandem mass spectrometry. The method validation criteria were satisfied by GC-AEI-MS/MS, which demonstrated acceptable measurement errors (MEs) ranging from -23.0 % to 19.5 %, recoveries between 81.6 % and 112.1 %, and precision levels below 10.1 %. Furthermore, the reliability and accuracy of the GC-AEI-MS/MS method were corroborated through Intraclass Correlation Coefficient (ICC) evaluation (values > 0.75), participation in external proficiency testing programs (G-EQUAS), and analysis of certified reference materials, which exhibited a relative deviation of <6.1 %. In summary, GC-AEI-MS/MS is a robust and reliable method for analyzing urine samples and conducting large-scale human biological monitoring. It was employed to determine 16 OH-PAHs in human urine as part of the China National Human Biomonitoring Program (CNHBM).
    Keywords:  Advanced electron ionization; Human urine; Hydroxyl polycyclic aromatic hydrocarbons; Mass spectrometry mode
    DOI:  https://doi.org/10.1016/j.chroma.2024.465521
  35. Talanta. 2024 Nov 15. pii: S0039-9140(24)01588-1. [Epub ahead of print]284 127209
    Utilizing two-dose difference combined with stable isotope tracing for effective and comprehensive metabolite identification of pioglitazone via ultra-high-performance liquid chromatography-mass spectrometry.
    Hui-I Yu, Yi-Shiou Chiou, Jie-Huei Wang, Meng-Chi Yen, Zih-Han Wu, Chia-Lung Shih.
      Drug metabolite identification is an essential characterization process spanning multiple phases of drug discovery and development. Various data processing techniques have been employed in metabolite identification using high-resolution mass spectrometry. However, metabolite identification is not consistent among approaches. Thus, a more comprehensive approach to drug metabolite identification is required. This paper proposes two-dose difference in conjunction with stable isotope tracing (SIT) to identify pioglitazone (PIO) metabolites. The results of this study revealed thatincubating both native and isotope-labeled PIOs in the same tube led to more stable metabolite identification compared with separated incubation. Our approach offers a high accuracy rate in metabolite identification, with approximately 70 % of metabolites validated as potential PIO metabolites. We compared our developed approach with other 3 approaches, namely the dose-response technique coupled with SIT, mass defect filter coupled with SIT, and orthogonal partial least squares-discriminant analysis. The results revealed that our developed approach was able to identify not only all the potential PIO metabolites identified by the other 3 approaches but also additional metabolites. These results suggest that two-dose difference coupled with SIT is an effective and comprehensive approach for drug metabolite identification.
    Keywords:  Dose–response technique; Mass defect filter; Stable isotope tracing; Two-dose difference; orthogonal partial least squares–discriminant analysis
    DOI:  https://doi.org/10.1016/j.talanta.2024.127209
  36. Biomed Chromatogr. 2024 Nov 18. e6049
    Determination of Sennoside A in Rat Plasma by Liquid Chromatography/Electrospray Ionization Tandem Mass Spectrometry and Its Application to a Rat Pharmacokinetic Study.
    Jingjing Sun, Yifan Gu, Chunyan Gu, Wen Qi, Feifei Chu, Jiawei Shen.
      To characterize pharmacokinetic profile of sennoside A in rats after intravenous and oral administration, a simple and sensitive liquid chromatography tandem mass spectrometry method was established and validated for quantitative determination of sennoside A in rat plasma. After prepared by protein precipitation with acetonitrile, sennoside A and internal standard were separated on a Waters ACQUITY HSS T3 (2.1 × 100 mm, 1.8 μm) column using acetonitrile and 5-mM ammonium acetate in water as mobile phase by gradient elution. The method showed excellent linearity over the range of 0.5-1000 ng/mL with acceptable intra- and inter-day precision, accuracy, matrix effect, and recovery. The stability assay indicated that sennoside A was stable in plasma during the sample collection, preparation, and analysis. Next, the method was applied to pharmacokinetic study of sennoside A in rats. After intravenous and intragastric administrated to rats, the concentrations of sennoside A in plasma at different time points were quantitated and the pharmacokinetic parameters were calculated by software of DAS 2.0. Pharmacokinetic parameters suggested that after oral administration, sennoside A was reached to the peak at 2.9-3.6 h with a Cmax value of 13.2-31.7 ng/mL. Sennoside A was eliminated slowly from the plasma with T1/2 value between 15.4 and 18.3 h. The oral absolute bioavailability was among 0.9%-1.3%, which indicated low blood exposure level.
    Keywords:  LC–MS/MS; method validation; pharmacokinetic; sennoside A
    DOI:  https://doi.org/10.1002/bmc.6049
  37. J AOAC Int. 2024 Nov 20. pii: qsae093. [Epub ahead of print]
    Validation of the QuEChERSER Method for 245 Pesticides and Environmental Contaminants in Barley and Hemp by Low-Pressure GC: Comparison of Triple Quadrupole MS/MS and Orbitrap HRMS for Qualitative and Quantitative Analysis.
    Nicolás Michlig, Steven J Lehotay.
       BACKGROUND: Monitoring labs are a fundamental link in the food safety chain, and regulatory demands in a competitive economy call for analytical methods that are simpler, faster, more rugged, and broader in scope. The QuEChERSER mega-method introduced in 2021 meets these monitoring needs, which includes high sample throughput, automated cleanup of extracts, and fast low-pressure gas chromatography (LPGC).
    OBJECTIVE: The goal of this work was to extend the QuEChERSER method to additional matrices and more analytes using LPGC, including comparison of the analytical performances of two different mass spectrometric (MS) analyzers: triple quadrupole tandem MS/MS and orbital ion trap (orbitrap) high-resolution (HR)MS.
    METHODS: The QuEChERSER mega-method was validated for 245 pesticides and environmental contaminants in barley grains and hemp pellets using automated instrument top sample preparation (ITSP) coupled with LPGC-MS/MS or LPGC-HRMS (orbitrap).
    RESULTS: Targeted MS/MS detection proved to be more sensitive than orbitrap using full data acquisition, leading to lower limits of quantification (LOQs) with more analytes yielding acceptable recoveries (70-120%) and repeatabilities (RSDs <20%). In barley, 89% of the compounds met validation criteria in MS/MS and 74% in HRMS, which in hemp were 81% and 66%, respectively. Qualitatively, orbitrap HRMS yielded 1% false positives compared to 3-4% in MS/MS, but due to the higher LOQs, the rates of false negatives were 14-17% in orbitrap vs. 6-10% in MS/MS for the different matrices.
    CONCLUSION: The QuEChERSER mega-method including ITSP+LPGC coupled with MS/MS or orbitrap analysis is a robust approach for multiple applications. In the comparison, MS/MS outperformed the orbitrap in terms of sensitivity, but the orbitrap advantages of easier method development, greater selectivity, and possibility for nontargeted/retrospective analysis permit even broader expansion of analytical scope in the future.
    HIGHLIGHTS: ITSP+LPGC- MS/MS or HRMS (orbitrap) analysis as part of the QuEChERSER mega-method is a useful and efficient way to monitor for contaminants in foods.
    DOI:  https://doi.org/10.1093/jaoacint/qsae093
  38. Sci Rep. 2024 Nov 20. 14(1): 28713
    A new chromatographic method for the determination of cysteine, glutathione, homocysteine and Nɛ-homocysteinyllysine isopeptide in human plasma.
    Kamila Borowczyk, Karolina Domagała, Grażyna Chwatko.
      Cysteine and glutathione can be applied as therapeutic targets in civilization diseases such as diabetes mellitus and cancers. On the other hand, an elevated concentration of homocysteine, and its metabolites such as homocysteine thiolactone and Nɛ-homocysteinyllysine result in health problems and has been indicated as an independent risk factor for cardiovascular disease and accelerated atherosclerosis. This work describes the first simplified HPLC-UV method that allows simultaneous determination of Nɛ-homocysteinyllysine isopeptide, cysteine, glutathione and homocysteine in human plasma. The assay is based on reversed-phase high performance liquid chromatography with UV detection and simultaneous reduction of disulfide bound with tris(2-carboxyethyl)phosphine and the selective pre-column derivatization of the thiol group with 1-benzyl-2-chloropyridinium bromide. Linearities of the detector responses for plasma samples were observed in ranges: 0.1-10.0 nmol/mL for Nɛ-homocysteinyllysine, 2.0-60.0 nmol/mL for glutathione and homocysteine, 20.0-600.0 nmol/mL for cysteine. The proposed method reduces the number of steps, shortens the total time of sample preparation, and limits the amount of single-use polypropylene laboratory materials.
    DOI:  https://doi.org/10.1038/s41598-024-79567-w
  39. Anal Bioanal Chem. 2024 Nov 22.
    Finding the ideal solvent for the analysis of polar analytes using supercritical fluid chromatography.
    Mo Legelli, Matti Froning, Michaela Wirtz, Stefan Lamotte.
      The analysis of polar analytes with the help of hydrophilic interaction liquid chromatography (HILIC) using classic methods of high-performance liquid chromatography is not without its downsides. In these applications, acetonitrile is prevalent as main eluent and sample diluent. This results not only in slow diffusion processes during the separation, but also in often unstable sample solutions where polar analytes are concerned. Furthermore, there are ecological concerns. With the use of supercritical fluid chromatography (SFC) which uses supercritical carbon dioxide as eluent, and other green solvents as alternative for the sample preparation, the separation of polar analytes could be vastly improved with this technique. Fast diffusion within carbon dioxide led to shorter analysis times and higher plate numbers. Regarding sample diluents, small alcohols such as ethanol and 2-propanol, as well as acetone, yielded promising results while analytes showed higher solubility and stability within these solvents compared to acetonitrile. Other green solvents such as dihydrolevoglucosenone (Cyrene) and dimethyl carbonate were found to be unsuitable sample diluents for applications in SFC.
    Keywords:  Green analytics; Green solvents; High-performance liquid chromatography; Hydrophilic interaction liquid chromatography; Supercritical fluid chromatography
    DOI:  https://doi.org/10.1007/s00216-024-05647-5
  40. BMC Plant Biol. 2024 Nov 20. 24(1): 1100
    NIRSpredict: a platform for predicting plant traits from near infra-red spectroscopy.
    Axel Vaillant, Grégory Beurier, Denis Cornet, Lauriane Rouan, Denis Vile, Cyrille Violle, François Vasseur.
      Near-infrared spectroscopy (NIRS) has become a popular tool for investigating phenotypic variability in plants. We developed the Shiny NIRSpredict application to get predictions of 81 Arabidopsis thaliana phenotypic traits, including classical functional traits as well as a large variety of commonly measured chemical compounds, based from near-infrared spectroscopy values based on deep learning. It is freely accessible at the following URL: https://shiny.cefe.cnrs.fr/NirsPredict/ . NIRSpredict has three main functionalities. First, it allows users to submit their spectrum values to get the predictions of plant traits from models built with the hosted A. thaliana database. Second, users have access to the database of traits used for model calibration. Data can be filtered and extracted on user's choice and visualized in a global context. Third, a user can submit his own dataset to extend the database and get part of the application development. NIRSpredict provides an easy-to-use and efficient method for trait prediction and an access to a large dataset of A. thaliana trait values. In addition to covering many of functional traits it also allows to predict a large variety of commonly measured chemical compounds. As a reliable way of characterizing plant populations across geographical ranges, NIRSpredict can facilitate the adoption of phenomics in functional and evolutionary ecology.
    Keywords:   Arabidopsis thaliana ; Functional traits; Genetic variability; Machine learning; Phenomics; Secondary metabolites; Trait prediction
    DOI:  https://doi.org/10.1186/s12870-024-05776-0
  41. J AOAC Int. 2024 Nov 19. pii: qsae092. [Epub ahead of print]
    FraMiTrACR: A Sustainable and Economical Technology for Analytical Sample Preparation.
    Jan-Michael Steils, Alexander Kaluza, Klaus Schöne, John Cashman, Christian Baumgartner, Maren Lang, Melina Kraus.
       BACKGROUND: There are several globally recognized methods for preparing laboratory samples. Of these, the QuEChERS and QuPPe methods are commonly used for food laboratory sample preparation. As an alternative, we developed the fractionation method using FraMiTrACR.
    OBJECTIVE: We present a life cycle assessment for the QuEChERS-, QuPPe- and FraMiTrACR methods. Our objective was to collect data to evaluate the carbon footprint of each method. However, as the ecological factors alone do not inform suitability of any given method, we also evaluated economic factors.
    METHODS: Our life cycle assessments followed ISO 14040/44 to determine the carbon footprint of each method. Also, we have analyzed existing data to support our comparison of all three methods.
    RESULTS: The mass of consumables and packaging for our FraMiTrACR method was observed to decrease by 45% and 34% from those required for the QuPPe and QuEChERS methods, respectively. Furthermore, we calculated a 43% reduction in carbon footprint when using FraMiTrACR compared to QuPPe and a 31% reduction compared to QuEChERS. In addition, we determined that our method offers time savings >87% and >71% compared to QuEChERS and QuPPe, respectively. The main economic benefit of FraMiTrACR comes from 84% and 70% labor cost savings compared to QuEChERS and QuPPe, respectively. The laboratory using fractionation method can process 320 samples with FraMiTrACR within 8 hours, an 87% increase in potential compared to QuEChERS and a 71% increase compared to QuPPe.
    CONCLUSIONS: Fractionation using FraMiTrACR is a more sustainable method for analytical sample preparation, offering the same quality of results and far-reaching economic advantages.
    HIGHLIGHTS: In comparison, FraMiTrACR uses up to 45% less consumables and packaging by weight and a reduction in kg CO2eq of up to 43%. In addition, the fractionation method offers up to 85% time savings and up to an 84% reduction in labor cost per sample.
    DOI:  https://doi.org/10.1093/jaoacint/qsae092
  42. Anal Bioanal Chem. 2024 Nov 16.
    Enhanced industrial wastewater monitoring: method development for non-target screening of highly polar substances using ZIC-HILIC-HRMS.
    Reyhaneh Armin, Jan Wachendorf, Markus Weber, Torsten C Schmidt.
      Non-target screening (NTS) plays a major role in the monitoring and management of water bodies. While the NTS of moderate to non-polar substances is well-established, the screening of highly polar chemicals remains challenging. In this study, a robust separation method for highly polar substances using zwitterionic hydrophilic interaction liquid chromatography coupled with high-resolution mass spectrometry (ZIC-HILIC-HRMS) was developed. This method was specifically designed for the NTS of industrial wastewater, with the objective of capturing a wide range of polar contaminants in each acquisition run. Method validation included assessing key parameters such as repeatability, reproducibility, linearity, and limit of detection (LOD). For repeatability and reproducibility, the average %RSD of intensity and retention time across all substances in different matrices-solvent, influent, and effluent-remained below 6% and 1%, respectively (n = 10). The method demonstrated good linearity (R2 > 0.99) for 75% of the substances, while LODs varied between 0.1 and 40 µg/L depending on the compound tested. The method was then applied for NTS analysis of untreated wastewater at various locations within a chemical industrial park. Additionally, the overall influent and effluent of an industrial wastewater treatment plant (WWTP) were monitored over a 10-day period. Principal component analysis (PCA) was performed to interpret the data, identifying irregularities in the wastewater content. Moreover, the method demonstrated the WWTP's ability to achieve an average removal efficiency of approximately 90% for this category of substances in this period, while also detecting their degradation products in the effluent. Finally, the method was successfully integrated into the daily monitoring routine of the WWTP, ensuring continuous surveillance and improved management of wastewater treatment processes.
    Keywords:  Highly polar compounds; Industrial wastewater; Non-target screening (NTS); Zwitterionic hydrophilic interaction liquid chromatography (ZIC-HILIC)
    DOI:  https://doi.org/10.1007/s00216-024-05635-9
  43. Food Chem. 2024 Nov 09. pii: S0308-8146(24)03600-8. [Epub ahead of print]465(Pt 1): 141950
    In vino veritas: A metabolomics approach for authenticating Provence Rosé wines.
    Katia Mekbel, Elnur Garayev, Nathalie Pouzalgues, Aurélie Chevallier, Gilles Masson, Sok-Siya Bun-Llopet, Béatrice Baghdikian, Gérald Culioli, Jean-Charles Martin.
      Provence rosé wines have gained global popularity, making them vulnerable to fraud. This study aimed to identify specific chemical markers to detect counterfeit Provence rosé wines. An untargeted LC-MS-based metabolomics analysis was performed on a set of 30 wines classified as "Provence," "Non-Provence," and "Provence imitations." Using the Molnotator workflow, 1300 potential metabolites were generated, and five key chemomarkers were selected through a machine learning pipeline. Further targeted analysis and bioinformatics using in silico MS/MS fragmentation systems confidently annotated three specific chemomarkers for "Provence" rosé: acuminoside, tetrahydroxydimethoxyflavone, and 5'-methoxycastavinol. A composite score using a PLS model combining the 3 chemomarkers effectively distinguished authentic wines, with high accuracy (sensitivity 83.3 %, specificity 100 %, accuracy 93.3 %).
    Keywords:  Food authenticity; Machine learning; Polyphenols; Rosé wines; Untargeted LC-MS-based metabolomics
    DOI:  https://doi.org/10.1016/j.foodchem.2024.141950
  44. Bioinform Adv. 2024 ;4(1): vbae142
    MetaboScope: a statistical toolbox for analyzing 1H nuclear magnetic resonance spectra from human clinical studies.
    Ruey Leng Loo, Javier Osorio Mosquera, Michael Zasso, Jacqueline Mathews, Desmond G Johnston, Jeremy K Nicholson, Luc Patiny, Elaine Holmes, Julien Wist.
       Motivation: Metabolic phenotyping, using high-resolution spectroscopic molecular fingerprints of biological samples, has demonstrated diagnostic, prognostic, and mechanistic value in clinical studies. However, clinical translation is hindered by the lack of viable workflows and challenges in converting spectral data into usable information.
    Results: MetaboScope is an analytical and statistical workflow for learning, designing and analyzing clinically relevant 1H nuclear magnetic resonance data. It features modular preprocessing pipelines, multivariate modeling tools including Principal Components Analysis (PCA), Orthogonal-Projection to Latent Structure Discriminant Analysis (OPLS-DA), and biomarker discovery tools (multiblock PCA and statistical spectroscopy). A simulation tool is also provided, allowing users to create synthetic spectra for hypothesis testing and power calculations.
    Availability and implementation: MetaboScope is built as a pipeline where each module accepts the output generated by the previous one. This provides flexibility and simplicity of use, while being straightforward to maintain. The system and its libraries were developed in JavaScript and run as a web app; therefore, all the operations are performed on the local computer, circumventing the need to upload data. The MetaboScope tool is available at https://www.cheminfo.org/flavor/metabolomics/index.html. The code is open-source and can be deployed locally if necessary. Module notes, video tutorials, and clinical spectral datasets are provided for modeling.
    DOI:  https://doi.org/10.1093/bioadv/vbae142
  45. J Chromatogr A. 2024 Nov 18. pii: S0021-9673(24)00915-4. [Epub ahead of print]1739 465541
    Room-temperature synthesis of fluorinated covalent organic framework coupled with liquid chromatography-mass spectrometry for determination of per- and polyfluoroalkyl substances in drinking water.
    Guiju Xu, Chunlei Yang, Hongwei Zhang, Baoyu Li.
      The routine monitoring of per- and polyfluoroalkyl substances (PFASs) in drinking water has become an important task in the field of public health. In this study, a fluorinated covalent organic framework (COF) was synthesized at room temperature using tetra-(4-aminophenyl) methane (TAM) and 2,3,5, 6-tetrafluoro-terephthalal (TFTA) as building blocks and named as TAM-TFTA-COF. The adsorption characteristics of PFASs on the TAM-TFTA-COF were investigated through adsorption model-fitting and molecular calculation. The TAM-TFTA-COF was served as the solid phase extraction (SPE) cartridge packing for the enrichment of PFASs. Combined with liquid chromatography-tandem mass spectrometry, the proposed method showed good linearity in the range of 1.25-375 ng·L-1, low limits of detection (0.03-0.24 ng·L-1), and excellent intraday and interday precisions with RSD <10.3 %. Furthermore, this analytical method can be utilized for the determination of PFASs in tap water, spring water, and lake water with satisfactory accuracy.
    Keywords:  Fluorinated covalent organic framework; HPLC–MS/MS; PFASs; Solid-phase extraction; water
    DOI:  https://doi.org/10.1016/j.chroma.2024.465541
  46. Biomed Chromatogr. 2024 Nov 19. e6048
    A Simple and Rapid HPLC Method Development for Quantification of Sodium Benzoate Content in Chlorzoxazone Oral Solid Dosage Forms.
    Prasanna Kumar Lankalapalli, Teja Kamireddy, Pranitha Sambu.
      The present study discusses the development of a simple, rapid, and specific HPLC method for the estimation of sodium benzoate in chlorzoxazone tablet dosage formulations. The current developed HPLC method was validated as per the current ICH guidelines. The chromatographic separation was achieved using a 0.02-M phosphate buffer adjusted to pH 3.0 with orthophosphoric acid as the buffer. Mobile phase A consisted of 100% buffer, and mobile phase B was a mixture of acetonitrile and buffer in a ratio of 80:20 (v/v). The column temperature was maintained at 30°C, the sample cooler at 25°C, and the flowrate at 0.8 mL min-1. The injection volume was 10 μL. The UV detection was performed at 230 nm for Sodium benzoate. The validated HPLC method was highly specific, with linearity ranging between 1.2 and 7.5 μg/mL for sodium benzoate, and the correlation coefficient was found to be > 0.999. The method showed high accuracy, exceeding 97%. The results demonstrate the successful applicability of the current method for the estimation of sodium benzoate in marketed formulations, which can be extended to assess other formulation systems. The developed method was validated as per international ICH guidelines with respect to specificity, linearity, precision, accuracy, and robustness. The method was applied to the analysis of stability samples.
    Keywords:  HPLC; chlorzoxazone; method development; sodium benzoate; validation
    DOI:  https://doi.org/10.1002/bmc.6048
  47. Bioanalysis. 2024 Nov 18. 1-12
    Green HPLC method for determination of paracetamol and ibuprofen in human plasma: applications to pharmacokinetics.
    Sally A Helmy, Heba M ElBedaiwy, Soha Am Helmy, Rama A Alamri, Renad Mh Alhusayni, Ibtihal Ay Almashhadi, Aryam Sg Alharbi, Shouq Ad Alharbi, Alaa A Ahmed-Anwar, Mahmoud A Mohamed.
      Using a straightforward, sensitive and precise liquid chromatographic approach, it is now possible to concurrently measure the amounts of ibuprofen (IBU) and paracetamol (PAR) in human plasma. A µ BondapakTM C18 column (300 mm × 3.9 mm, 15-20 μm) demonstrated acceptable separation when utilizing a mobile phase of 10 mM disodium hydrogen orthophosphate solution and acetonitrile at an 80:20, v/v ratio. The elution was isocratic at room temperature and a flow rate of 1.0 milliliters per minute. The UV detector was set to monitor PAR and IS (tinidazole) for 6.5 min at 254 nm, then IBU for the next 3 min at 220 nm. PAR and IBU showed linearity across the 0.05 to 100 µg/ml concentration range. The precision of the measurements ranged from 98.5% to 105% for PAR and from 95.1% to 102.8% for IBU. The average drug recovery rate was 100% for PAR and 98.9% for IBU. This method was effectively utilized to assess samples from an actual population administered PAR and IBU (325/200 mg) for pharmacokinetic research. The technique employs green and white tools to evaluate their environmental sustainability and efficacy. The suggested strategy was implemented utilizing the Six Sigma method.
    Keywords:  Green and white tools; HPLC-UV with time programming; Ibuprofen; Paracetamol; Six Sigma methodology; pharmacokinetics
    DOI:  https://doi.org/10.1080/17576180.2024.2421704
  48. Food Chem. 2024 Nov 09. pii: S0308-8146(24)03635-5. [Epub ahead of print]465(Pt 1): 141985
    Detection of Salmonella enterica in food using targeted mass spectrometry.
    Mengqi Chen, Miaoxi Peng, Muyun Yuan, Chengdong Huang, Jingwen Liu, Zuqing Wu, Wenrui Chen, Songqing Hu, Qing Liu, Jie Dong, Li Ling.
      The high prevalence of Salmonella enterica necessitates rapid and efficient detection methods. Targeted mass spectrometry (MS) using multiple reaction monitoring (MRM) and parallel reaction monitoring (PRM) has become a promising technique with improved specificity and sensitivity. We develop a novel targeted MS method for detecting S. enterica in food based on peptide biomarkers. Using a combination of four peptide biomarkers, this newly developed method could accurately distinguish S. enterica from other conventional food-borne pathogens. When combined with buoyant density centrifugation (BDC), Salmonella was efficiently separated from food matrices. Based on this discovery, this method was successfully applied to detect S. enterica in both artificially and naturally contaminated food samples, comparable to the culture method. These results demonstrate the potential of the targeted MS method in various food categories and are expected to be an alternative approach for S. enterica detection in food.
    Keywords:  Detection; Peptide biomarkers; Salmonella enterica; Targeted mass spectrometry
    DOI:  https://doi.org/10.1016/j.foodchem.2024.141985
  49. J Chromatogr A. 2024 Nov 14. pii: S0021-9673(24)00892-6. [Epub ahead of print]1739 465518
    Optimizing conditions in online RPLC × SFC for the analysis of complex samples containing neutral compounds: Solving injection issues.
    Jason Devaux, Mélanie Mignot, Morgan Sarrut, Guillaume Limousin, Carlos Afonso, Sabine Heinisch.
      The online combination of reversed-phase liquid chromatography and supercritical fluid chromatography (online RPLC × SFC) is an attractive technique for the characterization of complex samples containing neutral compounds as the two techniques are highly complementary, especially with a polar stationary phase in supercritical fluid chromatography (SFC). However, the setup is challenging due to the presence of hydro-organic solvents in RPLC, which become injection solvent in SFC. In this study, numerous key experimental parameters were identified and found to have a major effect on peak shape under RPLC × SFC conditions. These parameters included the organic modifier in reversed-phase liquid chromatography (RPLC), the co-solvent in SFC, the gradient conditions and the column ID in SFC, the configuration of the valve and finally, the injection volume in SFC that should be maximized. Acetonitrile (ACN) in RPLC, a mixture of ACN and methanol (MeOH) (50/50, v/v) in SFC, a minimum initial composition of 5% B in SFC, column IDs of 1.0 mm and 2.1 mm in RPLC and SFC respectively and flushing the interface loops with pure CO2 while adding the co-solvent after the valve, are all conditions that have been identified as perfectly suitable for online RPLC × SFC. They were successfully applied to the online RPLC × SFC separations of microalgae bio-oil samples. Despite unusual injection conditions, the peaks were symmetrical over the entire chromatogram, leading to a high separation power.
    Keywords:  Injection effect; Injection solvent; Microalgae bio-oil; Online RPLC × SFC; Valve configuration
    DOI:  https://doi.org/10.1016/j.chroma.2024.465518
  50. Anal Chem. 2024 Nov 21.
    Investigating the Kinetics of Heterogeneous Lipid Ozonolysis by an Online Photoionization High-Resolution Mass Spectrometry Technique.
    Peiqi Liu, Jigang Gao, Xintong Xiao, Wenhao Yuan, Zhongyue Zhou, Fei Qi, Meirong Zeng.
      Lipid oxidation-induced imbalance in the redox system is one of the key causative factors leading to accelerated aging in living organisms and related diseases. Online sampling and analysis of the heterogeneous ozonolysis kinetics of lipid aerosols are highly important in revealing the oxidation-driven aging process of lipids. In this paper, an online detection method based on atmospheric pressure photoionization combined with ultrahigh resolution mass spectrometry (APPI-HRMS) is developed for real-time analysis of the heterogeneous reactions between lipid particles (oleic acid and squalene) and ozone. The online APPI-HRMS technique serves as an ideal platform for analyzing the heterogeneous oxidation of particles, exhibiting remarkable stability, sensitivity, and responsiveness across a wide range of particle concentrations. Owing to the distinctive characteristics of soft ionization, the heterogeneous effective oxidation rate of lipid aerosols was quantitatively measured. This has facilitated the detection of a series of fingerprint particle-phase products, including aldehydes, secondary ozonides, and hydroperoxides. Additionally, the kinetics evolution of these products with the ozone concentration was captured. Consequently, the ability of this online APPI-HRMS technique in assessing the multiphase oxidation of organic particles has been demonstrated, positioning it as a promising and feasible tool for revealing the heterogeneous reactions of particles.
    DOI:  https://doi.org/10.1021/acs.analchem.4c04404
  51. J Chromatogr A. 2024 Nov 12. pii: S0021-9673(24)00889-6. [Epub ahead of print]1739 465515
    Designing boron-doped carbon dot-functionalized COFs for fluorescence screening and liquid chromatography tandem mass spectrometry detection of toxins.
    Yin-Hai Li, Fei Xu, Wei-Long Zhao, Xiao-Fan Tang, Feng Liu, Chun-Miao Bo.
      In recent years, mushroom poisoning has been one of the most important factors of food poisoning in China, timely identification of the toxins contained in mushrooms is crucial for the treatment of patients. In this study, boric acid carbon dots (BA-CDs) can undergo specific boron affinity reactions with amatoxins toxins containing o-dihydroxyl groups by means of boric acid groups. Functional covalent organic framework (COF) and BA-CDs were combined to design a adsorbent with boric acid group (COF@VBC@BA-CDs) was designed to meet the requirements of both fluorescent and pretreated materials for amatoxins. The mushrooms and urine samples were rapid screening using fluorescence detection, and then, for positive samples, the target analytes on the COF@VBC@BA-CDs are collected and eluted for next liquid chromatography tandem mass spectrometry (LC-MS/MS) detection. According to the fluorescence characteristics of COF@VBC@BA-CDs, the fluorescence quenching intensity was linearly correlated with the concentration (2-200 μg/L) and the detection limit was 1.2 μg/L. Meanwhile, the detection limit of LC-MS/MS was 0.5 μg/kg for musroom and 0.2 μg/L for urine, as well as the recovery rate was 72.7-110.1%. This noval method meets the methodological requirements and can be used for actual sample analysis.
    Keywords:  Amatoxins; Covalent organic framework; Fluorescence detection; Liquid chromatography tandem mass spectrometry
    DOI:  https://doi.org/10.1016/j.chroma.2024.465515
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