Rapid Communications in Mass Spectrometry最新文献

{"title":"Detection of LGD-4033 Metabolites in Camel Urine, Plasma, and Hair Following Oral Administration for Doping Control","authors":"Praseen Ondern Komathu,&nbsp;Syed Ali M Padusha,&nbsp;Laya Saraswathy,&nbsp;Jahfar Nalakath,&nbsp;Christiana Hebel,&nbsp;Ansar Babu Palathinkal,&nbsp;Rasheed Naduvilakkandy","doi":"10.1002/rcm.9989","DOIUrl":"10.1002/rcm.9989","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>LGD-4033, a selective androgen receptor modulator (SARM), is recognized for promoting muscle growth and enhancing athletic performance. Its potent anabolic effects have led to its prohibition in both human and animal sports. Although initial in vitro studies have offered insights into its metabolism, an in-depth in vivo analysis is necessary to fully understand its metabolic pathways. This research aims to thoroughly investigate the metabolic profile of LGD-4033 in camels to establish reliable analytical markers, thereby addressing an important gap in the doping detection in camel racing.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Urine, plasma, and hair samples were collected from three healthy camels following a single oral administration of 100 mg LGD-4033 mixed with food. These biological samples were then analyzed using ultrahigh-performance liquid chromatography coupled with high-resolution Q Exactive Orbitrap mass spectrometry (UHPLC-HRMS).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Fourteen metabolites were identified across all sample types. The main Phase I metabolite, <b>M6</b> (dihydroxylation), appears to be a primary target analyte for urine-based doping analysis. Both dihydroxy and trihydroxy metabolites were notably abundant in urine, accompanied by glucuronic and sulfonic acid conjugates; however, sulfonic acid conjugates were absent in in-vitro studies. Further research on hair samples, especially at higher LGD-4033 dosages, is recommended.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The findings from this study will improve the rapid identification of LGD-4033 and related compounds, supporting effective doping control in camel racing. These results enhance understanding of LGD-4033 metabolism in camels and advance the development of reliable methods for detecting SARMs in this field.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143055773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isolation and Identification of Mercury–Dissolved Organic Matter Complexes in Mercury–Humic Acid Suspensions","authors":"Ghulam Hussain Qasim,&nbsp;Lisa Harris,&nbsp;Vaughn Mangal,&nbsp;Mario Montesdeoca,&nbsp;Svetoslava Todorova,&nbsp;Charles Driscoll","doi":"10.1002/rcm.9986","DOIUrl":"10.1002/rcm.9986","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>The complexation with dissolved organic matter (DOM) is a pivotal factor influencing transformations, transport, and bioavailability of mercury (Hg) in aquatic environments. However, identifying these complexes poses a significant challenge because of their low concentrations and the presence of coexisting ions.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>In this study, mercury–dissolved organic matter (Hg-DOM) complexes were isolated through solid-phase extraction (SPE) from Hg–humic acid suspensions, and complexes were putatively identified using ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Dissolved organic carbon (DOC) and total Hg analysis before and after SPE showed an increase in DOC:Hg ratio. The DOC:Hg ratio was lower in extracts from cartridges with silica structure bonded with hydrocarbon chains (C18) than priority pollutant (PPL) cartridges at circumneutral pH, indicating that C18 was more effective at extracting DOM complexed Hg. These results were confirmed with FTICR-MS analysis, where two Hg-DOM complexes were putatively identified from PPL extracts as opposed to eight from C18 (Winnow score &gt; 75%). In addition, C₈H₁₃HgN₂O₂S, a molecular formula with a <i>m/z</i> ratio of 403.04, was identified across three separate extractions using a C18 cartridge, suggesting that the complexes were preserved during extraction and, presumably, electrospray ionization.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The results highlight the effectiveness of the methodology developed in this study—SPE coupled with FTICR-MS for isolating and identifying Hg-DOM complexes. This approach allows for the exploration of the elemental and structural composition of Hg-DOM complexes, which affects Hg speciation, bioavailability, and transformations in aquatic ecosystems.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Synopsis</h3>\u0000 \u0000 <p>A methodology was developed to identify Hg-DOM complexes at low concentrations to gain insight into mercury bioavailability, transformations, and transport in the environment.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11730372/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142976747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metabolomic Analysis of Patients With Patent Foramen Ovale and Migraine Using Liquid Chromatography-Mass Spectrometry Technology","authors":"Paerhati Tuerxun,&nbsp;Peng-fei Gong,&nbsp;Dilimulati Nizhamuding,&nbsp;Yan Yang,&nbsp;Hai-tao Ye,&nbsp;Yang Xie,&nbsp;Xiu-fen Li","doi":"10.1002/rcm.9972","DOIUrl":"10.1002/rcm.9972","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objective</h3>\u0000 \u0000 <p>This study aims to examine the changes in metabolic profiles in patients with patent foramen ovale (PFO) and migraine, as well as in patients with isolated migraine, before and after surgical intervention using metabolomics.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Patients were categorized into four groups: the simple migraine (SM) group, the PFO with migraine preoperative group (PRE), the PFO with migraine postoperative Day 3 group (POST_3d), and the PFO with migraine postoperative Day 30 group (POST_30d). Untargeted metabolomics using liquid chromatography–mass spectrometry (LC-MS) were employed to identify differential metabolites across these groups. Differential metabolites were identified, their clinical diagnostic value was assessed, and a correlation analysis was conducted to examine changes in metabolic pathways before and after surgery.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The expression levels of metabolites such as linoleic acid, quinolinic acid, homophenylalanine, and amphetamine showed significant changes in patients with PFO and migraine following surgery. Notably, linoleic acid demonstrated strong diagnostic potential for this patient population. Trend analysis revealed that the levels of 3-phenylpropionic acid and caffeine decreased on postoperative Day 3 and subsequently increased by postoperative Day 30, whereas gallic acid continuously declined. Compared to the PRE group, differential metabolites in the SM group were primarily associated with α-linolenic acid metabolism, niacin and nicotinamide metabolism, sphingolipid signaling, and tyrosine metabolism. In contrast, differential metabolites in the POST_3d group were predominantly enriched in phenylalanine metabolism, niacin and nicotinamide metabolism, protein digestion and absorption, and caffeine metabolism.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>Linoleic acid may serve as a potential biomarker, and the activation of inflammation and oxidative stress-related pathways could contribute significantly to the development of complicated migraine in patients with PFO.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 6","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142968819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiclass Steroid Profiling in Short-Finned Pilot Whale Blubber Using Liquid Chromatography–Tandem Mass Spectrometry (LC-MS/MS)","authors":"Jillian H. Wisse,&nbsp;Douglas P. Nowacek,&nbsp;Ashley S. P. Boggs","doi":"10.1002/rcm.9965","DOIUrl":"10.1002/rcm.9965","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Wildlife scientists are quantifying steroid hormones in a growing number of tissues and employing novel methods that must undergo validation before application. This study tested the accuracy and precision of liquid chromatography–tandem mass spectrometry (LC-MS/MS) methods for use on blubber samples from short-finned pilot whales (<i>Globicephala macrorhynchus</i>). We expanded upon a method for corticosteroid quantification by adding analytes and optimizing internal standard (IS) application.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>We optimized a method for the quantification of seven steroid hormones using LC-MS/MS with a C18 column. We assessed the accuracy and precision of this updated C18 method and an existing biphenyl method for use with pilot whale blubber by conducting a spike recovery experiment and calculating percent recovery and relative standard deviation (RSD) for each analyte. To explore the potential for running this method with fewer matched ISs, we compared the performance of multiple ISs for each analyte.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>All 11 adrenal and gonadal analytes showed good accuracy and precision in the spike recovery experiment, with recoveries between 82% and 110% and recovery RSDs below 10%. The C18 method detected all analytes at endogenous concentrations, except aldosterone. Although endogenous DHEA was detected, variability was high. IS comparisons showed 10 of 11 analytes could be calculated with comparable accuracy and precision using an IS substitute, but some substitutions significantly altered the analyte concentrations calculated.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Discussion</h3>\u0000 \u0000 <p>The C18 method was not sensitive enough for endogenous aldosterone detection. DHEA, which has not been previously quantified in blubber, was detected in all samples, but with high variability at lower concentrations. The methods in this study provide reliable detection and quantification of the other nine hormones tested and can be used for assessments of adrenal and gonadal steroid hormones from whales. Laboratories can reduce costs through IS substitution but should consider how these substitutions affect results.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 6","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142968820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of Chemical Components of Penicillium chrysogenum Crude Extract Using Liquid Chromatography Coupled With Q-Exactive Orbitrap Mass Spectrometry Combined With GNPS Molecular Networking","authors":"Ya Lu,&nbsp;Jiao Yang,&nbsp;Kun Ma,&nbsp;Jiahui Qi,&nbsp;Jessica Villegas-Moreno","doi":"10.1002/rcm.9984","DOIUrl":"10.1002/rcm.9984","url":null,"abstract":"<div>\u0000 \u0000 <p>A Chinese isolate of the fungus <i>Penicillium chrysogenum</i> was analyzed using liquid chromatography coupled with Q-Exactive Orbitrap mass spectrometry combined with Global Natural Products Social Networking (GNPS) on culture condition leading to the rapid identification of 20 secondary metabolites. Among them are eight polyketones, two phthalides, six diketopiperazine alkaloids, and others. A meleagrine network was examined and proposed as a promising candidate for new natural products.</p>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 7","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142968833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Systematic Characterization of the Chemical Constituents of in Vitro and in Vivo of Astragali Radix-Salvia miltiorrhiza Herb Pair by Ultra-High-Performance-Liquid Chromatography-Orbitrap Mass Spectrometry","authors":"Lexin Shu,&nbsp;Shumin Zhang,&nbsp;Jun Qian,&nbsp;Sitong Liu,&nbsp;Huixin Qiu,&nbsp;Qiduo Zhao,&nbsp;Yanru Deng,&nbsp;Yubo Li","doi":"10.1002/rcm.9977","DOIUrl":"10.1002/rcm.9977","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Astragali radix-<i>Salvia miltiorrhiza</i> (AR-SM) is an herb pair with good therapeutic effects and is widely used. In this study, the in vitro and in vivo components of AR-SM were quickly classified and identified based on UHPLC-orbital mass spectrometry. This provided a basis for clarifying the bioactive substances after compatibility of AR and SM.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Firstly, the related literature of AR and SM were searched through PubMed and CNKI databases, and the molecular formula, retention time, mass spectrum fragments, and other information of its chemical components were sorted out to establish a component database. Extract, blank plasma and drug-containing plasma were analyzed by UHPLC orbital mass spectrometry technology, and then the data were processed by Xcalibur software. Combined with databases and literature, the in vivo and in vitro components of AR-SM were comprehensively analyzed.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>A total of 142 components were identified in the extract of AR-SM. The cleavage patterns of flavonoids, terpenoids, phenolic acids, organic acids, saponins, and phenylpropanoids were summarized. Meanwhile, 89 compounds were tentatively identified in rat plasma, including 73 prototypes and 16 metabolites. The main metabolic pathways included oxidation, reduction, methylation, glucuronidation, and sulfation.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142942088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Long-Term Storage on the Isotopic Compositions of Different Types of Environmental Waters","authors":"Carlynn Diersing,&nbsp;Yue Li,&nbsp;Lixin Wang","doi":"10.1002/rcm.9988","DOIUrl":"10.1002/rcm.9988","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Fog, dew, and rain are crucial for sustaining ecosystem functions, especially in water-limited regions. However, they are subject to isotopic changes during storage due to their usual small sample volumes and inherent sensitivity to atmospheric particulates. Understanding long-term storage effects on these water samples is essential for ensuring isotopic integrity.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>In this study, the extent of such changes in the isotopic compositions (δ²H, δ¹⁸O, and δ¹⁷O) of fog, dew, and rain was investigated under different storage times (4.5–9 years) and different bottle fill levels (4.8%–92.4%) using the Los Gatos Research Inc. GLA431 series analyzer.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The long-term storage could lead to a large variation in oxygen isotopes of fog with minor effects on dew and rain samples. The isotopic changes of δ¹⁸O for fog waters were negatively correlated with the bottle fill level (<i>p</i> &lt; 0.01) but positively related to storage time (<i>p</i> &lt; 0.01). Chemical reactions between solutes and water molecules within fog samples may induce oxygen fractionation, leading to the high sensitivity of fog oxygen isotopes to long-term storage. No significant changes in δ²H values were observed for the three water types.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Our findings could help understand the long-term isotopic accuracy and precision of fog, dew, and rainwaters by providing information on isotopic changes after long-term storage.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11718355/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142942087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Covalent Organic Framework Nanofilm-Assisted Laser Desorption Ionization Mass Spectrometry for Rapid Screening of Parabens in Personal Care Products","authors":"Wenjun Zheng,&nbsp;Jingjing Yan,&nbsp;Yingxue Jin,&nbsp;Zian Lin,&nbsp;Zongwei Cai","doi":"10.1002/rcm.9987","DOIUrl":"10.1002/rcm.9987","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rational</h3>\u0000 \u0000 <p>People are widely exposed to parabens in their daily life, but parabens are endocrine disrupting chemicals that pose a threat to human health. Therefore, establishing a rapid screening method to enhance monitoring of parabens is necessary. Herein, a covalent organic framework (COF) nanofilm-assisted laser desorption ionization mass spectrometry (LDI-MS) method was established to screen parabens in personal care products (PCPs).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>TAPB-TFPB-COF nanofilm was synthesized on indium tin oxide (ITO) glass and used as LDI-MS substrates. To observe the practicability of TAPB-TFPB-COF nanofilm-assisted LDI-MS, the results of this method for analyzing small molecules such as parabens, estrogens, and bisphenols were compared with those of the conventional organic matrix 9-aminoacridine (9-AA), and the reproducibility and detection limit were further verified. Finally, the method was applied to screen parabens in PCPs.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>TAPB-TFPB-COF nanofilm-assisted LDI-MS analyzed small molecules such as parabens, estrogens, and bisphenols with higher mass spectral signals and cleaner mass spectral backgrounds compared with 9-AA. Meanwhile, the method analyzed methylparaben (MeP) with high reproducibility (RSD = 6.96%) and low detection limit (1.64 μM) and performed well for rapid screening of parabens in PCPs.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>TAPB-TFPB-COF nanofilm-assisted LDI-MS for analyzing small molecules such as parabens, estrogens, and amino acids offered the advantages of rapid analysis, a clean background, and good reproducibility. The method was successfully applied to detecting parabens in PCPs, demonstrating the practical utility of LDI-MS based on TAPB-TFPB-COF nanofilm for analyzing parabens in complex samples.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 7","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142942086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Guidelines for Accurate and Precise Stable Isotope Analysis of Calcite, Dolomite, and Magnesite Using a Carbonate Device for Continuous Flow-Isotope Ratio Mass Spectrometry (CF-IRMS)","authors":"Soujung Kim,&nbsp;Sang-Tae Kim,&nbsp;Martin Knyf","doi":"10.1002/rcm.9958","DOIUrl":"10.1002/rcm.9958","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Carbonate minerals are one of the most popular samples for an automated sample preparation system for CF-IRMS, such as GasBench II and iso FLOW, but no standardized analytical protocols exist. This study gives guidelines on optimal analytic conditions for carbon and oxygen isotope analysis of Ca–Mg carbonates when using the carbonate–phosphoric acid reaction method.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Calcite (CaCO₃–McMaster Carrara), dolomite (CaMg(CO₃)₂–MRSI Dolomite), and magnesite (MgCO₃–ROM Brazil Magnesite) with two grain size fractions (&lt; 74 and 149–250 μm) were reacted with 103% (specific gravity of 1.92) phosphoric acid under He atmosphere in 12-mL borosilicate glass vials to examine the full <i>δ</i>¹³C and <i>δ</i>¹⁸O evolution of acid-liberated CO₂ for an extended reaction time of up to 12–30 days at 25°C and up to 3–7 days at 72°C.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>At 25°C, the optimal reaction time of calcite is 1 day for both grain size fractions while the optimal reaction time of 2–10 day is suggested for dolomite with a grain size of &lt; 74 μm. At 72°C, 30-min to 12-h or 45-min to 12-h reaction is optimal for calcite with &lt; 74-μm or 149- to 250-μm grain size fraction, respectively, whereas dolomite requires 12-h to 1-day reaction for both grain size fractions. The only optimal condition for magnesite is 6–7 days of reaction with &lt; 74-μm grain size at 72°C.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>To determine precise and accurate <i>δ</i>¹³C and <i>δ</i>¹⁸O values of a carbonate mineral using the carbonate–phosphoric acid reaction method, an optimal reaction time must be assessed for a given analytical condition to avoid nonequilibrium isotope effects and unnecessary oxygen isotope exchange of acid-liberated CO₂ in the carbonate reaction vessel. Our experimental result provides a guideline for the accurate and precise stable isotope analysis of Ca–Mg carbonate minerals.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 5","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11715619/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142942085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"LCMS Detection and Characterization of In Vitro Metabolites of Isotonitazene, a Targeted Strategy for Novel Psychoactive Substance Control in Camel Racing","authors":"Jahfar Nalakath,&nbsp;Rasik P. Thacholil,&nbsp;Ahmed Kadry,&nbsp;Shamil P,&nbsp;O. K. Praseen","doi":"10.1002/rcm.9982","DOIUrl":"10.1002/rcm.9982","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>The use of benzimidazole-class novel psychoactive substances has significantly increased worldwide raising concerns about potential misuse and doping in animal sports such as camel racing. Understanding the metabolism of these substances is critical for developing reliable detection methods to ensure fair competition and animal welfare.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p><i>In vitro</i> studies were conducted using homogenized camel liver samples to replicate metabolic processes. Metabolites were extracted and analyzed with a Thermo Fisher Orbitrap Exploris LCMS system. The acquired data were processed using the Compound Discoverer software for accurate detection and characterization of the metabolites.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Through <i>in vitro</i> investigation, we have successfully identified nine metabolites in camels, which provide valuable insights into their metabolic pathways. The primary pathways for the formation of phase I metabolites were dealkylation and hydroxylation; the characterized metabolites can be used for long-term detection of the presence of isotonitazene.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>The study employed advanced high-resolution accurate mass LC–MS techniques to detect and identify the <i>in vitro</i> metabolites of isotonitazene in camels. Isotonitazene is a highly active psychoactive substance with significant potential for abuse, particularly in racing contexts. These findings are crucial for developing effective doping control strategies, which will improve regulation and monitoring in camel racing events and promote animal welfare.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 7","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142930187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}