Rapid Communications in Mass Spectrometry最新文献

{"title":"Method of Confirmation and Predictive Metabolomics: A Novel Multidimensional Analytical Framework for Characterizing New Psychoactive Substances","authors":"Anirudha Dixit,&nbsp;Aakanksha Soni,&nbsp;Astha Pandey","doi":"10.1002/rcm.10116","DOIUrl":"10.1002/rcm.10116","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>The rapid emergence and structural diversity of new psychoactive substances (NPS) present significant challenges for forensic drug analysis. Existing targeted methods often fall short in accurately identifying novel compounds, increasing the risk of false positives or missed detections. This study aims to address this gap by developing a robust, non-targeted analytical approach capable of confidently screening, identifying, and confirming a broad range of NPS.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Method</h3>\u0000 \u0000 <p>A method was developed using Ultra-Performance Liquid Chromatography coupled with Quadrupole Time-of-Flight Mass Spectrometry (UPLC-QTOF-MS) to analyze four selected NPS: Mephedrone (4-methylmethcathinone), Ephylone, 2C-B, and Methamphetamine. Analytical parameters such as retention time, mass accuracy (±5 ppm), diagnostic fragments, ion ratios, and isotope patterns were evaluated. The method was validated against critical criteria including precision, stability, and reproducibility. The limit of confirmation (LOC) for each analyte was established, and predictive metabolomics were performed to investigate metabolic transformations using bulk powder spiking and spiked urine matrices.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The UPLC-QTOF-MS method demonstrated excellent precision and reproducibility, with consistent retention times and diagnostic fragment ions within acceptable limits as per SANTE and WADA TD2023IDCR guidelines. Mass accuracy remained within ±5 ppm, confirming high analytical performance. The established LOC for all analytes was 50 ng/mL. The study also revealed significant metabolic transformations through predictive metabolomics. Compared to conventional tandem MS techniques, QTOF-MS offered enhanced non-targeted screening capabilities and the advantage of retrospective data analysis.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>The validated UPLC-QTOF-MS method provides a powerful, reliable tool for the rapid detection and confirmation of emerging NPS in forensic samples. Its high mass accuracy, ability to perform non-targeted analysis, and support for retrospective interrogation make it a superior alternative to traditional mass spectrometric methods. This approach enhances forensic laboratories' ability to keep pace with evolving drug trends and strengthens the integrity of drug-related investigations.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 22","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144773770","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":"Methodological Considerations for the Use of Acid-Based Pre-Treatment Protocols for Carbon and Oxygen Analysis of Tooth Enamel","authors":"Karolina Varkulevičiūtė,&nbsp;Christine Winter-Schuh,&nbsp;Cheryl A. Makarewicz","doi":"10.1002/rcm.10090","DOIUrl":"10.1002/rcm.10090","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Chemical pre-treatment is a common methodological step aimed to remove exogenous materials introduced to archaeological tooth enamel in the burial environment through diagenetic processes. However, some of these methods, involving the use of oxidising reagents such as NaClO, H₂O₂, as well as weak acids like CH₃COOH, have been shown to alter the chemical composition and stable isotope values of enamel. Here, we aim to re-examine the effects of commonly used pre-treatment protocols on bioapatite <i>δ</i>¹³C and <i>δ</i>¹⁸O values, and investigate the relationship between diagenetic alteration and measured isotope values, as indicated by pre-screening using attenuated total reflectance-Fourier transform infrared (ATR–FTIR) spectroscopy.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Modern and archaeological samples were subjected to 10 commonly used pre-treatment protocols that apply NaClO, H₂O₂ and/or CH₃COOH to tooth enamel powders at treatment lengths. Preservation status and diagenetic alteration prior to and after treatment were investigated using ATR–FTIR. <i>δ</i>¹³C and <i>δ</i>¹⁸O values were measured before and after treatment to determine if different wet chemistry protocols induced isotopic shifts.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The results show that all pre-treatment protocols imparted shifts in <i>δ</i>¹³C and <i>δ</i>¹⁸O values of up to ± 1.5‰ in both archaeological and modern samples. Most treated samples display increased crystallinity, likely indicating sample recrystallisation. We suggest that these changes indicate the removal of contamination and diagenetic alteration, and also the dissolution and restructuring of enamel carbonate leading to changes in the in vivo isotope signal.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>We discourage the use of H₂O₂ and NaClO to remove organic matter from samples as it incurs unwanted changes to the enamel structure and carbon and oxygen isotope ratios. We also recommend the use of only short-duration acetic acid treatment protocols to avoid recrystallisation caused by prolonged acid exposure and concomitant unwanted change to in vivo isotope values.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 20","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/rcm.10090","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144751289","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":"Assessing the Quantitative Performance of Atmospheric Solids Analysis Probe-Mass Spectrometry","authors":"Alisha Henderson,&nbsp;Stephanie Rankin-Turner,&nbsp;James C. Reynolds,&nbsp;Matthew A. Turner,&nbsp;Ashley Sage,&nbsp;David Douce,&nbsp;Mario Thevis,&nbsp;Liam M. Heaney","doi":"10.1002/rcm.10112","DOIUrl":"10.1002/rcm.10112","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Atmospheric solids analysis probe-mass spectrometry (ASAP-MS) is an established ambient ionisation technique that allows for the direct and rapid analysis of samples without chromatographic separation. Consequently, applications that typically benefit from ambient ionisation approaches can achieve improved sample throughput and thus improved potential for in situ testing. Previous reports have contrasted in viewpoints on the ability for ASAP-MS to provide reliable quantitative data. Critically, in-depth data exploring the quantitative capabilities of ASAP-MS are currently lacking.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Here, a series of experiments were performed to assess the quantitative performance of ASAP-MS using a proof-of-concept single analyte (caffeine) approach. Analytical precision, accuracy, linearity and sensitivity were investigated using numerous variables, including sample deposition method (i.e., directly placing the probe into the sample vs. pipetting the sample onto the probe) and deposition volume, as well as the presence of a series of different internal standard approaches.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The data acquired demonstrated that the use of a positive displacement pipette and an isotopically labelled (structure-matched) internal standard provided an optimal approach for quantitative reliability, albeit at levels often below the standards set for traditional chromatography-based quantitative assays. The investigations were performed across a concentration range of 50–5000 ng/mL. Whereas measurable responses were seen across the full range in most approaches, limitations in sensitivity were identified and reduced quantitative performance statistics were noted at concentrations below 1000 ng/mL.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>These experiments demonstrate, for the first time, a comprehensive investigation into the quantitative performance of ASAP-MS using caffeine as the example analyte. These data offer insight into the current strengths and limitations of quantitative analyses using ASAP-MS and aim to provide practical recommendations to optimise quantitative approaches using this technique.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 22","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/rcm.10112","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144751596","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":"LC–MS Determination of Trichloroethylene Glutathione Conjugation Metabolites in a Parkinson's Disease Mouse Model","authors":"Dan Li,&nbsp;Ling Yan,&nbsp;Thomas Ka-Yam Lam,&nbsp;Zongwei Cai","doi":"10.1002/rcm.10117","DOIUrl":"10.1002/rcm.10117","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rational</h3>\u0000 \u0000 <p>Investigating TCE glutathione (GSH) conjugation metabolites is essential, as these reactive intermediates play a central role in TCE bioactivation and are implicated in organ-specific toxicities, including nephrotoxicity, hepatotoxicity, and neurotoxicity. Characterizing and quantifying these metabolites enhances our understanding of TCE metabolism, supports biomarker discovery, and helps elucidate mechanisms of TCE-induced toxicity.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>A robust liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was established for the detection and quantification of three major GSH-related TCE metabolites: S-(1,2-dichlorovinyl)-glutathione (DCVG), S-(1,2-dichlorovinyl)-L-cysteine (DCVC), and N-acetyl-S-(1,2-dichlorovinyl)-L-cysteine (NAcDCVC). Serum samples were obtained from male C57BL/6 mice chronically exposed to TCE (100 ppm in drinking water for 15 weeks).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Calibration curves for all three metabolites demonstrated excellent linearity (<i>R</i>² &gt; 0.998). The method achieved limits of detection (LOD) ranging from 0.0057 to 0.0120 nM, limits of quantitation (LOQ) from 0.0189 to 0.0401 nM, recoveries of 75.9%–115.5%, and inter-assay variation of 0.5%–11.5%. PD model mice exhibited elevated serum levels of DCVG and DCVC, while NAcDCVC levels were significantly reduced.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>This study presents the first comprehensive LC–MS/MS-based quantification of TCE GSH conjugation metabolites in serum, offering high sensitivity, precision, and reproducibility. The observed elevated serum levels of the toxic metabolites DCVG and DCVC, along with the markedly reduced NAcDCVC concentrations in PD mice, provide a critical foundation for future investigations into the mechanistic links between TCE exposure and PD pathogenesis.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 21","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144725400","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":"Methylclostebol Metabolism Discovery by Untargeted Analysis","authors":"G. Barone,&nbsp;L. C. Harps,&nbsp;L. Liu,&nbsp;D. Jardines,&nbsp;M. K. Parr,&nbsp;F. Botrè,&nbsp;X. de la Torre","doi":"10.1002/rcm.10114","DOIUrl":"10.1002/rcm.10114","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>This work introduces an alternative experimental approach by integrating high-resolution mass spectrometry (HRMS) with multivariate statistical analysis for metabolite detection and identification. The integration of these tools maximizes information extraction from data, improving accuracy and reducing the risk of false identifications.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Seven volunteers' urine samples were collected before and after oral administration of 10 mg of methylclostebol (4-chloro-17β-hydroxy-17α-methylandrost-4-en-3-one, ClMT) and assigned to three excretion time intervals. Analyses were carried out on a GC–HRMS system (Agilent 8890 GC coupled with 7250 GC/QTOF), utilizing low-energy electron ionization (&lt; 18 eV) to preserve the native molecular skeleton, thereby simplifying mass spectrum interpretation, with acquisition in full scan mode. Raw data were then processed and subjected to multivariate analysis.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The orthogonal partial least squares-discriminant analysis (OPLS-DA) was employed to emphasize differences among specific sample conditions, and features that significantly contribute to classification in the OPLS-DA can be identified as important biomarkers. Samples from the three excretion intervals demonstrated clear separations, occupying distinct areas within the model's defined space. From this approach, the S-plot displayed seven features identified as biomarkers related to methylclostebol ingestion, comparing their mass spectra with an in-house library of LE-EI mass spectra.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The application of this approach is demonstrated to enhance the identification of new markers related to the intake of prohibited substances in the anti-doping field, such as methylclostebol. Its application proved to be an alternative strategy that allows for gathering a more comprehensive range of information in the antidoping field.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 21","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144716663","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":"Characterization of 12 Unknown Photodegradation Impurities of Tunlametinib Capsules Using Liquid Chromatography Coupled With ion Trap/Time-Of-Flight Mass Spectrometry","authors":"Ying Yang,&nbsp;Jiarui Gao,&nbsp;Hongxia Zeng","doi":"10.1002/rcm.10113","DOIUrl":"10.1002/rcm.10113","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>In March 2024, tunlametinib capsules, a Class 1 new drug (referring to active pharmaceutical ingredients and formulations not previously marketed either nationally or globally), were approved in China for treating patients with advanced melanoma and neuroblastoma RAS viral oncogene homologue mutations who experienced disease progression or intolerance to anti-PD-1/PD-L1 therapy. Risk assessment of impurity profiles is essential for drug safety and efficacy in clinical applications. This study characterized impurity profiles in tunlametinib capsules induced by photodegradation.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Initial high-performance liquid chromatography coupled with ion trap/time-of-flight mass spectrometry (HPLC/IT-TOF MS) in positive ion mode was first performed to determine the <i>m</i>/<i>z</i> values of protonated ions and predict the formulas of the detected impurities. Subsequent LC-MSⁿ analyses (<i>n</i> = 2–4) of target compounds elucidated comprehensive structural features.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Twelve previously unidentified photodegradation impurities in tunlametinib capsules were characterized using HPLC/IT-TOF MS.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Structural elucidation of 12 previously uncharacterized photodegradation impurities was achieved through HPLC/IT-TOF MS. These findings establish a scientific foundation for refining quality specifications of tunlametinib.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 21","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144716556","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":"In Vitro Metabolism of Metonitazene in Camels: High-Resolution Mass Spectrometric Characterization for Doping Control","authors":"Jahfar Nalakath,&nbsp;Ansar Babu Palathinkal,&nbsp;Rasheed Naduvilakkandy,&nbsp;Ramees Abdulla Vazhat,&nbsp;Praseen Ondern Komathu","doi":"10.1002/rcm.10111","DOIUrl":"10.1002/rcm.10111","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Novel psychoactive substances, especially those within the benzimidazole class such as metonitazene, are powerful psychoactive agents with considerable potential for misuse in both human and animal sports. Implementing a robust detection and monitoring system is crucial to ensure fair competition and welfare of the athletes involved.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>In vitro studies were conducted using camel liver homogenates to investigate the metabolism of metonitazene in camels. The metabolites were analyzed using a Thermo Fisher Orbitrap Exploris LC–MS system. Method validation for qualitative determination was performed using in-house developed methods, while data analysis and metabolite identification were performed using the Compound Discoverer software.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>A total of seven Phase I metabolites of metonitazene were successfully identified. The metabolic transformations were predominantly characterized by dealkylation reactions. These metabolites hold promise as potential markers for the long-term detection of metonitazene in camels for doping control applications.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>This study highlights the effectiveness of advanced high-resolution LC–MS techniques in identifying and characterizing the in vitro metabolites of metonitazene in camels. Considering the high potency and potential for abuse of metonitazene in camel racing, the metabolites identified offer a valuable basis for establishing robust doping control strategies. These results support the development of regulatory frameworks designed to protect animal welfare and uphold the integrity of the sport.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 21","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144714771","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":"A Robust and Accurate Filter Paper–Based Dried Plasma Spot Method for Bictegravir Monitoring in HIV Therapy","authors":"Arpita Sathyanarayanan,&nbsp;Roopashri N. Arekal,&nbsp;Divyashree Somashekara","doi":"10.1002/rcm.10110","DOIUrl":"10.1002/rcm.10110","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Context</h3>\u0000 \u0000 <p>Therapeutic drug monitoring (TDM) involves the collection of biological samples such as blood, plasma, urine, and saliva. The most commonly used biological matrix for the detection of drugs is either blood or plasma, as they are widely accepted by the regulatory authorities. Such studies require a significant amount of blood to be collected and even more if the study is performed in a plasma sample. The growing demand to minimize the blood or biological samples required for the study of drugs, dried blood spot, or the dried plasma spot techniques has been studied by its demand.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Objective</h3>\u0000 \u0000 <p>The main aim was the development of a novel method for the determination of the circulating blood plasma levels in clinical samples using spotted and dried plasma on filter paper as a substrate detection of bictegravir, an HIV integrase strand transfer inhibitor (INSTI) drug from dried plasma spots.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Materials and Methods</h3>\u0000 \u0000 <p>The quantitation, as well as the detection of the plasma drug concentration, was done using liquid chromatography–tandem mass spectrometry LC-MS/MS. Sixty microliters of plasma spiked with 2% of the drug was spotted on Whatman filter paper and was left to dry at room temperature. The drug was extracted using methanol as a precipitating agent.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The extraction technique yielded a recovery of 100%. The assay exhibited excellent linearity in the range of 20–1200 ng/mL.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Discussion and Conclusion</h3>\u0000 \u0000 <p>The method developed is a robust, simple, and accurate method to extract drug from the plasma. This method enables to produce a clean sample, proving to be cheaper and more accurate with maximum recovery.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 21","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/rcm.10110","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144705525","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":"Blood Collection Tube has Minimal Interference on the Carbon and Nitrogen Isotope Composition of Plasma, Red Blood Cells, and Serum in Cow Blood","authors":"David M. Jaramillo,&nbsp;Lisa M. Bauman,&nbsp;Carlos Henrique Paiva Camisa Nova,&nbsp;Lais Lima,&nbsp;Edzard van Santen","doi":"10.1002/rcm.10109","DOIUrl":"10.1002/rcm.10109","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Stable isotopes can be useful for tracking diet composition and other physiological processes in ruminants. These techniques rely on the fact that tissues directly reflect the animal's diet. Blood is a dynamic tissue that can be separated into serum, plasma, and red blood cell (RBC) components. Numerous collection tubes for blood are commercially available. No studies have compared the isotopic composition from cattle blood as affected by collection tube. This study compared commercially available serum and plasma tubes and evaluated how they may affect δ¹³C, δ¹⁵N, and C and N concentrations from blood in lactating dairy cattle.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>For plasma and RBC, treatments were five collection tubes containing different anticoagulants: dipotassium ethylenediaminetetraacetic acid (K2EDTA), tripotassium EDTA (K3EDTA), NaF/K oxalate, Li heparin (LiHep), and Na heparin (NaHep). For serum analysis, the three collection tubes were a RedTop (contained no coagulating agent) and TigerTop and Red+CAT, which both contained clot activator and serum separator gel, each made by two different manufacturers. All samples were collected via tail venipuncture in cows. All samples were processed, freeze dried, and analyzed in triplicate for δ¹³C, δ¹⁵N, and C and N.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>While mean differences exist on the δ¹³C and δ¹⁵N from plasma and red blood cells, differences were minimal. Clot activator gels in serum tubes did not affect the δ¹³C and δ¹⁵N composition. This study showed that, while isotopic values may differ slightly from different blood collection tubes, these differences were often small, which may have little impact on the interpretation of research results when serum or RBC are analyzed. The isotopic composition of C and N concentrations of serum was not affected by the three tubes used within this study. Researchers will have to understand these differences and decide whether or not these may impact the objectives and the results of a given study.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 21","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144688143","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":"Acid Fractionation Factor of Oxygen Isotopes in Mixed Calcite–Dolomite Samples: Implications for Data Correction","authors":"Linlin Cui,&nbsp;Xu Wang,&nbsp;Lianjun Feng,&nbsp;Xiaomei Zhang","doi":"10.1002/rcm.10108","DOIUrl":"10.1002/rcm.10108","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>The conventional method for measuring carbon and oxygen isotopes in carbonates involves the reaction of carbonate minerals with phosphoric acid (PPA) to generate CO₂, followed by purification and isotopic analysis. During this reaction, a temperature-dependent oxygen isotope acid fractionation factor (AFF) is introduced, as not all oxygen is released in CO₂. Although the temperature dependence of AFF has been extensively studied in pure carbonate minerals, little research has been conducted on AFF variations in mixed carbonate minerals with diverse chemical and mineralogical compositions. This study aims to investigate the range of AFF variations in carbonates containing multiple mineral phases.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Oxygen isotope compositions of CO₂ produced from CaCO₃-MgCO₃ mixed minerals reacting with PPA at 25°C, 50°C, 70°C, and 90°C were analyzed using a GasBench II system coupled with a Thermo Finnigan Delta V Plus isotope ratio mass spectrometer.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The AFF values for CaCO₃-MgCO₃ mixed minerals fall between those of pure calcite and dolomite, generally aligning with theoretical predictions. Additionally, the fractionation gradient (dδ¹⁸O/dT⁻¹) increases with rising mole Mg and dolomite content, indicating a systematic trend in fractionation behavior.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>These findings provide a framework for AFF correction based on mole Mg or dolomite content, enhancing the reliability and precision of oxygen isotope measurements in natural impure carbonates.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 21","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144672714","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}