Rapid Communications in Mass Spectrometry最新文献

{"title":"Remembering Robert Kinnear Boyd (1938-2024).","authors":"Pierre Thibault, Dietrich Volmer, David Goodlett, John Monaghan","doi":"10.1002/rcm.9963","DOIUrl":"https://doi.org/10.1002/rcm.9963","url":null,"abstract":"","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":" ","pages":"e9963"},"PeriodicalIF":1.8,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142805724","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":"Forced Degradation Study of an Anti-Diabetic Drug Imeglimin: Impurity Profiling and Structure Elucidation Using LC-Q-ToF-MS/MS and NMR","authors":"Shiva Kumar Gogikar,&nbsp;Sibu Sen,&nbsp;Shivashankar Pathinti,&nbsp;Gananadhamu Samanthula,&nbsp;Amol G. Dikundwar","doi":"10.1002/rcm.9960","DOIUrl":"10.1002/rcm.9960","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>The present study aims to establish structures of the degradation products of an anti-diabetic drug, Imeglimin (IMG) approved for the treatment of type 2 diabetes mellitus in the year 2021. Degradation pathways are proposed along with in silico toxicity assessments of the observed degradation products (DPs) of the drug.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>A reversed-phase high-performance liquid chromatography (RP-HPLC), equipped with a photodiode array detector, was used to separate the observed DPs with a Phenomenex Luna PFP (250 × 4.6 mm, 5 μm) column, using 10 mM ammonium formate (pH 4.5) and methanol as mobile phase. Liquid chromatography quadrupole time of flight mass spectrometry (LC-Q-ToF-MS/MS) and nuclear magnetic resonance (NMR) spectroscopy were employed for structural elucidation. Zeneth and Derek suites were used for in silico assessments.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>A total of four degradation products were observed, which were successfully separated on an RP-HPLC. The structural characterization of three of the four DPs was achieved using LC-Q-TOF-MS/MS by employing electro spray ionization as well as atmospheric pressure chemical ionization. Additionally, DP-3 was isolated using a preparative HPLC and was characterized by NMR. Computationally predicted structures were compared with the experimental observations.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>An HPLC method, capable of separating the Imeglimin and its four DPs, was developed and validated as per the ICH Q2(R1) guideline. Structure elucidation reveals a variety of products with metformin as one of the identified DPs along with a metabolite. The toxicity potential of DPs was assessed through docking studies.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 5","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142805726","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 simple and cost-effective sample preparation and storage method for stable isotope analysis of atmospheric CO2 for GasBench II/continuous flow isotope ratio mass spectrometry","authors":"Savio Manaj,&nbsp;Sang-Tae Kim","doi":"10.1002/rcm.9941","DOIUrl":"10.1002/rcm.9941","url":null,"abstract":"<div>\u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>The stable isotope compositions of atmospheric CO₂ can provide useful insight into various geochemical processes and carbon cycles on Earth, which is critical for understanding of Earth's changing climate. Here, we present a simple and cost-effective analytical method for the collection and measurement of carbon and oxygen isotope compositions of atmospheric CO₂.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Air samples of ~150 mL were collected individually or collectively using our simple active air collection system and then extracted on a vacuum purification line to remove noncondensable gases and atmospheric water vapor. The efficiency of removing atmospheric water vapor was tested by using a magnesium perchlorate desiccant trap and a dry ice/ethanol trap. Lastly, a “J-Cut tube sealing/cracking method” was developed to store and transfer purified atmospheric CO₂ to the GasBench II and CF-IRMS system for δ¹³C and δ¹⁸O measurements.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The collective active air collection method combined with the full sample air extraction method for a 3-min transfer time or “Full 3m TE” yields the best analytical precision of 0.07‰ (δ¹³C) and 0.04‰ (δ¹⁸O). Removing atmospheric water vapor from air samples is not necessary for δ¹³C, but essential for δ¹⁸O measurements. The J-Cut tube sealing/cracking method shows a near 100% effectiveness for the storage and transfer of atmospheric or any CO₂.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>A simple and cost-effect method was developed for the collection, purification, storage, and isotopic analysis of indoor/outdoor atmospheric CO₂ samples for general users. This method utilizes a popular headspace gas sample preparation system for CF-IRMS and an easy-to-build vacuum purification line without involving complex and high-cost devices for the preparation of atmospheric CO₂.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11625694/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142794076","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":"Testing the Ce Limit of Mass Bias Correction Using 145Nd/142Nd as Normalizing Ratio in Radiogenic Neodymium Isotope Analysis by MC-ICP-MS","authors":"Torben Struve,&nbsp;Martin Zander,&nbsp;Katharina Pahnke","doi":"10.1002/rcm.9951","DOIUrl":"10.1002/rcm.9951","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Neodymium isotopes are a powerful geochemical tool that has widely been used in terrestrial and extraterrestrial studies. Modern multicollector inductively coupled plasma mass spectrometers (MC-ICP-MS) allow fast, accurate, and precise analysis of the radiogenic Nd isotope ratio ¹⁴³Nd/¹⁴⁴Nd. These analyses comprise relatively high instrumental mass bias that is typically corrected for using the stable ¹⁴⁶Nd/¹⁴⁴Nd of 0.7219 and an exponential law. The instrument is usually tuned to optimize the operating conditions for isotope analysis, but this tuning is a trade-off primarily between signal intensity, stability, and accuracy. Alternative, more effective approaches for mass bias correction have been proposed that use ¹⁴⁵Nd/¹⁴²Nd as normalizing ratio. However, one drawback of using this ratio is that the efficient removal of Ce from Nd is required to minimize the effect of isobaric interference of ¹⁴²Ce on ¹⁴²Nd.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Here, we analyzed international Nd and rock reference materials using a Thermo Scientific Neptune <i>Plus</i> MC-ICP-MS to evaluate the sensitivity of ¹⁴⁵Nd/¹⁴²Nd-based mass bias correction to varying Ce/Nd and in comparison with the commonly used ¹⁴⁶Nd/¹⁴⁴Nd-based correction.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Our results show that the corrected ¹⁴³Nd/¹⁴⁴Nd of Ce-doped JNdi-1 and Ce-containing USGS BCR-2, NOD-A-1, and NOD-P-1 reference materials are insensitive to Ce/Nd of up to ~1.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The correction of instrumental mass bias with ¹⁴⁵Nd/¹⁴²Nd as a normalizing ratio yields, as previously suggested, improved trueness and precision of ¹⁴³Nd/¹⁴⁴Nd data in comparison with ¹⁴⁶Nd/¹⁴⁴Nd-based corrections, even under high Ce/Nd of ~1. This allows improved optimization of signal intensity during instrument tuning, which is particularly useful for natural samples with low Nd content. [Correction added on 10 December 2024, after first online publication: The Results and Conclusions in Abstract has been corrected in this version.]</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11623368/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142783592","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":"Correction to “The ‘LSVEC problem’ for the Vienna Peedee belemnite carbon isotope-delta scale”","authors":"","doi":"10.1002/rcm.9962","DOIUrl":"10.1002/rcm.9962","url":null,"abstract":"&lt;p&gt;\u0000 &lt;span&gt;Dunn, PJH&lt;/span&gt;, &lt;span&gt;Camin, F&lt;/span&gt;. &lt;span&gt;The ‘LSVE problem’ for the Vienna Peedee belemnite carbon isotope-delta scale&lt;/span&gt;. &lt;i&gt;Rapid Commun Mass Spectrom&lt;/i&gt;. &lt;span&gt;2024&lt;/span&gt;; &lt;span&gt;38&lt;/span&gt;(&lt;span&gt;17&lt;/span&gt;):e9841. https://doi.org/10.1002/rcm.9841.\u0000 &lt;/p&gt;&lt;p&gt;The authors have been made aware of some errors in referencing as well as inclusion of data considered unpublished within Figure 3 of the article entitled “&lt;i&gt;The “LSVEC problem” for the Vienna Peedee belemnite carbon isotope-delta scale&lt;/i&gt;” (RCM 28 e9841) [1]. These errors include the following:&lt;/p&gt;&lt;p&gt;Firstly, the data series named “Assonov et al (2015)” within Figure 3 should not have been included as it is considered unpublished data. This error does not alter the discussion surrounding the assigned isotope delta value of LSVEC within the text linked to the figure. A correct version of the Figure with caption is given here (reference numbering as per the original article):&lt;/p&gt;&lt;p&gt;The third paragraph of Section 5.4 of the paper (entitled “Proposal 2 – maintain only the VPDB scale and remove LSVEC entirely”) also has incorrect citations in the final parenthesis. This should read “&lt;i&gt;(see e.g. Table 9 of Qi et al&lt;/i&gt; [18] &lt;i&gt;and Hélie et al&lt;/i&gt; [19],&lt;i&gt;)&lt;/i&gt;.” These errors were inadvertently introduced during typesetting and unfortunately not corrected during proofing.&lt;/p&gt;&lt;p&gt;The authors wish to thank Sergey Assonov for bringing most of these errors to their attention and apologise for any inconvenience caused.&lt;/p&gt;&lt;p&gt;\u0000 1. &lt;span&gt;P. J. H. Dunn&lt;/span&gt; and &lt;span&gt;F. Camin&lt;/span&gt;, “ &lt;span&gt;The ‘LSVEC problem’ for the Vienna Peedee belemnite carbon isotope-delta scale&lt;/span&gt;,” &lt;i&gt;Rapid Communications in Mass Spectrometry&lt;/i&gt;. &lt;span&gt;38&lt;/span&gt;, no. &lt;span&gt;17&lt;/span&gt; (&lt;span&gt;2024&lt;/span&gt;): e9841, https://doi.org/10.1002/rcm.9841.\u0000 &lt;/p&gt;&lt;p&gt;\u0000 8. &lt;span&gt;T. B. Coplen&lt;/span&gt;, &lt;span&gt;W. A. Brand&lt;/span&gt;, &lt;span&gt;M. Gehre&lt;/span&gt;, et al., “ &lt;span&gt;New Guidelines for δ13C Measurements&lt;/span&gt;,” &lt;i&gt;Analytical Chemistry&lt;/i&gt; &lt;span&gt;78&lt;/span&gt;, no. &lt;span&gt;7&lt;/span&gt; (&lt;span&gt;2006&lt;/span&gt;): &lt;span&gt;2439&lt;/span&gt;–&lt;span&gt;2441&lt;/span&gt;, https://doi.org/10.1021/ac052027c.\u0000 &lt;/p&gt;&lt;p&gt;\u0000 13. &lt;span&gt;P. Ghosh&lt;/span&gt;, &lt;span&gt;M. Patecki&lt;/span&gt;, &lt;span&gt;M. Rothe&lt;/span&gt;, and &lt;span&gt;W. A. Brand&lt;/span&gt;, “ &lt;span&gt;Calcite-CO2 mixed into CO2-free air: a new CO2-in-air stable isotope reference material for the VPDB scale&lt;/span&gt;,” &lt;i&gt;Rapid Communications in Mass Spectrometry&lt;/i&gt;. &lt;span&gt;19&lt;/span&gt;, no. &lt;span&gt;8&lt;/span&gt; (&lt;span&gt;2005&lt;/span&gt;): &lt;span&gt;1097&lt;/span&gt;–&lt;span&gt;1119&lt;/span&gt;, https://doi.org/10.1002/rcm.1886.\u0000 &lt;/p&gt;&lt;p&gt;\u0000 14. &lt;span&gt;R. M. Verkouteren&lt;/span&gt; and &lt;span&gt;D. B. Klinedinst&lt;/span&gt;, &lt;span&gt;Value Assignment and Uncertainty Estimation of Selected Light Stable Isotope Reference Materials: RMs 8543–8545, RMs 8562–8564, and RM 8566&lt;/span&gt; (National Institute of Standards and Technology, &lt;span&gt;2004&lt;/span&gt;).\u0000 &lt;/p&gt;&lt;p&gt;\u0000 ","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 4","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/rcm.9962","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142783594","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":"In-Source Collision-Induced Dissociation (CID) Improves Higher-Energy Collisional Dissociation (HCD)-Dependent Fragmentation of ADP-Ribosyl Peptides","authors":"Taku Kasai,&nbsp;Yuto Nakamura,&nbsp;Masanori Aikawa,&nbsp;Sasha A. Singh","doi":"10.1002/rcm.9961","DOIUrl":"10.1002/rcm.9961","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>ADP-ribosylation is a posttranslational modification whose higher-energy collisional dissociation (HCD) products are dominated by complete or partial modification losses, complicating peptide sequencing and acceptor site localization efforts. We tested whether in-source collision-induced dissociation (CID) performed on a quadrupole-Orbitrap could convert ADPr to the smaller phosphoribose-H₂O derivative to facilitate HCD-dependent peptide sequencing.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>ADP-ribosyl (ADPr) peptides derived from the human macrophage-like cell line THP-1 were analyzed on a quadrupole-Orbitrap. We monitored the dissociation of ADPr (+ 541.061 Da) to phosphoribosyl-H₂O (+ 193.997 Da) peptides while varying the source and high-field asymmetric waveform ion mobility mass spectrometry (FAIMS) compensation voltages. Xcorr and ptmRS were used to evaluate peptide sequencing and acceptor site confidence, respectively. Phosphoribosyl-H₂O acceptor sites were compared with those determined by electron-transfer higher-energy collision dissociation (EThcD), performed on a quadrupole-ion trap-Orbitrap.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>In-source CID of ADPr peptides to their phosphoribosyl-H₂O derivatives increased with increasing source voltage (up to 50 V), as judged by monitoring the corresponding modification loss ([adenosine monophosphate/AMP]⁺) and the number of identified phosphoribosyl-H₂O peptide identifications. The average Xcorr increased from 1.36 (ADPr) to 2.26 (phosphoribosyl-H₂O), similar to that achieved with EThcD for ADPr peptides (2.29). The number of high-confidence acceptor sites (&gt; 95%) also increased, from 31% (ADPr) to 70% (phosphoribosyl-H₂O), which was comparable to EThcD (70%).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>In-source CID converts ADP-ribosyl to phosphoribosyl-H₂O peptides that are more amenable to HCD-dependent peptide sequencing, providing an alternative method for acceptor site determination when ETD-based methods are not available.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 4","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11617611/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142778924","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":"Assessment of Serum Metabolism and Eicosanoid Profiling in Pediatric Asthma and Bronchiolitis via Liquid Chromatography-Mass Spectrometry","authors":"Xiao-huan Gao,&nbsp;Tian-lu Yin,&nbsp;Yan Li,&nbsp;Su-fang Shi,&nbsp;Feng-li Liu,&nbsp;Miao-jing Li,&nbsp;Rui-xin Liu,&nbsp;Qing Liu,&nbsp;Yan-li Xu","doi":"10.1002/rcm.9955","DOIUrl":"https://doi.org/10.1002/rcm.9955","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Asthma, a prevalent chronic inflammatory respiratory disease among children, was the focus of this study. Serum metabolism profiles were examined in patients diagnosed with both asthma and bronchiolitis by using ultra-high performance liquid chromatography-mass spectrometry.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>In this study, the serum samples from three distinct groups—comprising patients diagnosed with asthma, bronchiolitis, and a healthy control group—underwent comprehensive non-targeted metabolomics analysis and targeted eicosanoid profiling.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Through both univariate and multivariate analyses, significant associations were observed between the pathophysiology of both asthma and bronchiolitis and aberrations in the metabolism of polyunsaturated fatty acids, amino acids, purines, and pathways involving cyclooxygenases and lipoxygenases, indicative of inflammatory processes and immune responses. Furthermore, metabolic changes in phosphatidylethanolamine, saturated and monounsaturated fatty acids, and bile acids were observed in the asthma group. Bronchiolitis was distinguished by disruptions in acyl carnitine and phosphatidylcholine metabolism.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>This study offers a new perspective on understanding the interplay of pathogenic mechanisms underlying both asthma and bronchiolitis. Its findings are significant for enhancing the diagnostic and therapeutic strategies tailored to asthma stemming from bronchiolitis.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 4","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762362","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":"Electron Transfer Dissociation of Alkali-Cationized Phosphatidylcholines Allows Easy Double Bonds and sn-1/sn-2 Localizations","authors":"John Carlos,&nbsp;Clarisse Gosset-Erard,&nbsp;Jean-Yves Salpin,&nbsp;Salomé Poyer","doi":"10.1002/rcm.9956","DOIUrl":"https://doi.org/10.1002/rcm.9956","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>The emergence of new mass spectrometry (MS) dissociation methods has highlighted lipid isomers as new biomarkers. Only a few commercial methods without derivatization are available to characterize phosphatidylcholines (PCs) at the isomeric level. We propose to use electron transfer dissociation (ETD) as a method to determine the position of both double bonds and stereo numbering (<i>sn</i>) on glycerol for PC species.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Doubly charged PCs were analyzed using alkali salts to promote the formation of [PC + 2Alk]²⁺ species. ETD-MS² experiments were performed using a quadrupole ion trap mass spectrometer with an ESI source to annotate <i>sn</i>-positions. ETD-CID-MS³ experiments were then done on ETnoD [M + 2Alk]^+• or [M + 2Alk−N(CH₃)₃]^+• species to localize double bond positions. Density functional theory (DFT) calculations and cyclic ion mobility spectrometry c-IMS-MS/MS experiments were used to support fragmentation assumptions.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>ETD-MS² experiments exhibit a systematic <i>sn</i>-2 favorable cleavage, allowing <i>sn</i>-positioning through a radical cation-driven mechanism supported by DFT calculations. This behavior contrasts with CID experiments, in which the initial positioning of alkali cations influences ester bond cleavage, as shown by c-IMS-MS/MS experiments. The dissociation process studied for ETD-CID-MS³ experiments on 10 different PC isomers allowed us to localize double bonds for either monounsaturated or polyunsaturated species.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The dissociation rules established for ETD-MS² and ETD-CID-MS³ experiments on PC isomers enable their annotation at the isomeric level without instrumental modification or complex sample preparation. This method could be easily coupled to LC separation using post-column introduction of an alkali salt for complex mixture analysis.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 4","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762107","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":"Detection and Identification of New Chlorphenesin Carbamate Metabolites in Human Urine and Metabolomic Characterization Using Liquid Chromatography-Q Exactive-HF-Orbitrap-Mass Spectrometry","authors":"Wennuo Xu,&nbsp;Bing Niu,&nbsp;Zhongquan Li,&nbsp;Yue Zhuo,&nbsp;Siyan Xu,&nbsp;Bing Liu,&nbsp;Xiaojun Deng","doi":"10.1002/rcm.9959","DOIUrl":"https://doi.org/10.1002/rcm.9959","url":null,"abstract":"<div>\u0000 \u0000 <p>Chlorphenesin carbamate is a skeletal muscle relaxant, and one of its metabolites is 4-chlorophenoxyacetic acid (4-CPA), which is included on the Prohibited List of the World Anti-Doping Agency (WADA). The non-prohibited substance, chlorphenesin carbamate, as a potential source of 4-CPA, needs to be identified more strongly in doping control protocols. In this paper, the metabolism of chlorphenesin carbamate in human urine was studied. Ten volunteers were recruited to take chlorphenesin carbamate tablets orally, and urine samples were collected before and after being tested. The urine samples were detected by liquid chromatography-Q Exactive HF orbitrap mass spectrometry (LC-Q Exactive HF-MS) in full MS and full MS-ddMS² scanning modes. Based on accurate molecular formulae determination and fragmentation pattern analysis by mass spectrometry, a total of 29 chlorphenesin carbamate metabolites were found, comprising 18 newly identified metabolites and 11 previously reported metabolites. There were five potential metabolic processes listed: hydroxylation, amide hydrolysis, C-oxidation, O-glucuronidation, sulfation, and their combinations. Chlorphenesin carbamate and the 29 metabolites were compared for their detection windows, and the findings indicated that the two recently reported metabolites, M9 and M10, had longer detection windows than the metabolites documented by the WADA. These metabolites are anticipated to be long-lasting biomarkers for the detection of chlorphenesin carbamate intake. By analyzing the results of metabolomic profiling, it was found that the metabolites with significant changes were mainly related to histidine metabolism and β-alanine metabolism pathways. This paper provides a comprehensive report on the metabolic profile of urinary chlorphenesin carbamate and reveals a point of view the changes in the metabolic in the human body, which is conducive to supporting the detection of chlorphenesin carbamate and meclofenoxate for doping control, as well as a better understanding of the mechanism of action of chlorphenesin carbamate as a drug.</p>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 4","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762359","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":"Cupressus torulosa, a Source of Antioxidant Polyphenols: An Analytical and Pharmacological Study","authors":"Radhika Khanna,&nbsp;H. R. Chitme,&nbsp;Khushaboo Bhadoriya,&nbsp;V. K. Varshney","doi":"10.1002/rcm.9945","DOIUrl":"https://doi.org/10.1002/rcm.9945","url":null,"abstract":"<div>\u0000 <section>\u0000 <h3> Introduction</h3>\u0000 <p><i>Cupressus torulosa</i> (family Cupressaceae), widely distributed in the northwestern Himalayan region of India, is a coniferous aromatic tree traditionally used for its aerial parts. Its needles are renowned for their anti-inflammatory, anticonvulsant, antimicrobial, and wound-healing properties. Antioxidants from this plant are vital in combating oxidative stress, which are implicated in these diseases.</p>\u0000 </section> \u0000 <section>\u0000 <h3> Methods</h3>\u0000 <p>This study employed a range of methods, including in vitro, in vivo, and ex vivo assays; biochemical estimations such as Total Phenolics Content and Total Flavonoids Content; and UPLC-QTOF-MS analysis, to evaluate the antioxidant potential of <i>Cupressus torulosa</i> needles.</p>\u0000 </section>\u0000 <section>\u0000 <h3> Results</h3>\u0000 <p>Initial screenings demonstrated promising antioxidant activity of 25% aqueous methanol extract of the needles, with SGOT and SGPT values of 55.28±57.07 and 52.27±19.50 IU/L, respectively, when compared to the positive control glibenclamide. Fractionation of the extract into ethyl acetate and butanol fractions revealed that the ethyl acetate fraction showed notable activity, with an EC50 value of 85.6 μg/mL in the DPPH assay, indicating effective free radical scavenging and reduced oxidative damage. UPLC-QTOF-MS characterization of ethyl acetate fraction in negative ion mode identified 34 metabolites, including 10 key antioxidant compounds.</p>\u0000 </section> \u0000 <section>\u0000 <h3> Conclusion</h3>\u0000 <p>These findings underscore <i>C. torulosa’s</i> potential as a source of bioactive antioxidants, highlighting its value for pharmaceutical and nutraceutical applications. The research provides a foundation for further isolation, characterization, and clinical testing of these compounds, enhancing our understanding of natural antioxidants in addressing oxidative stress-related conditions.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142764065","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}