Rapid Communications in Mass Spectrometry最新文献

{"title":"Characterization of Larvicidal Diterpene Resin Acids in Melipona quadrifasciata Geopropolis via LC-ESI-MS/MS, GC–MS and Computational Analysis","authors":"Luís Guilherme Pereira Feitosa,&nbsp;Juliana Massimino Feres,&nbsp;Camila Capel Godinho,&nbsp;Lorena Carneiro Albernaz,&nbsp;Laila Salmen Espindola,&nbsp;Ricardo Vessecchi,&nbsp;Thais Guaratini,&nbsp;Norberto Peporine Lopes","doi":"10.1002/rcm.10025","DOIUrl":"10.1002/rcm.10025","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Dengue, an arboviral disease transmitted by the <i>Aedes aegypti</i> mosquito, is a major global public health problem challenge. Insecticides based on natural products can provide a good alternative to synthetic agents, as they are safer for both the environment and human health. This study evaluated the activity of geopropolis from stingless bees and <i>Apis mellifera</i> bees on <i>Ae. aegypti</i>, using mass spectrometry approaches to identify compounds with larvicidal potential against <i>Ae. aegypti</i>.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>The larvicidal activity of propolis from stingless bees and <i>A. mellifera</i>, as well as the <i>Melipona quadrisfasciata</i> geopropolis (a mixture of soil/clay and propolis), was evaluated against <i>Ae. aegypti</i> larvae (Rockefeller strain). ESI-MS/MS analyses were performed using a quadrupole/time-of-flight mass spectrometer for all geopropolis samples, the geopropolis from <i>Melipona quadrifasciata</i> was also analyzed using an ion trap instrument. The ESI-qTOF-MS/MS data were processed in a spectral similarity network using GNPS. Molecular annotation of potential compounds was performed using the <i>in silico</i> tool called NAP. Gas-phase fragmentation mechanisms were proposed in conjunction with computational chemistry studies. Silylated geopropolis samples were also analyzed by GC–MS.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Geopropolis from the stingless bee <i>M. quadrifasciata</i> caused 90% and 100% mortality in <i>Ae. aegypti</i> larvae after 24 and 48 h of exposure, respectively, exhibiting the highest activity. Mass spectrometry-based molecular network approach supported the suggestion of discriminant compounds between active and inactive samples. The combination of NAP predictions with gas-phase reactions from ESI-MS/MS and EI-MS data facilitated the annotation of larvicidal compounds, including diterpene resin acids, such as dehydroabietic acid and its derivatives, abietic acid, and pimaranes.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>The combination of HPLC-MS/MS and GC–MS data suggests that diterpene resin acids contribute to the larvicidal effect of <i>M. quadrifasciata</i> geopropolis on <i>Ae. aegypti</i>, enhancing our understanding of potentially bioactive natural products against the arbovirus vector.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 12","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143672933","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":"Surface Ionization of Carbaryl, Papaverine, Cocaine, Morphine, and Triethylamine by Heated Surface-Oxidized Metal Filaments of W, Re, Pd, Mo, Ti, and SUS304 Under Atmospheric Pressure: Ionization Mechanism","authors":"Kenzo Hiraoka,&nbsp;Dilshadbek T. Usmanov,&nbsp;Sherzod M. Akhmedov,&nbsp;Stephanie Rankin-Turner,&nbsp;Satoshi Ninomiya","doi":"10.1002/rcm.10029","DOIUrl":"10.1002/rcm.10029","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>The objective of the present study is to investigate the ionization mechanisms for atmospheric pressure surface ionization (APSI).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>APSI of carbaryl, papaverine, cocaine, morphine, and triethylamine using heated surface-oxidized metal filaments of W, Re, Pd, Mo, Ti, and SUS304 were measured by mass spectrometry. Low-volatility analytes dissolved in methanol were desorbed by Leidenfrost phenomenon-assisted thermal desorption and introduced to the heated metal filament used as an emitter. Alkylamine benzene solutions were simply placed 10 mm below the filament.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Carbaryl, papaverine, cocaine, and morphine (M) gave protonated molecules [M+H]⁺ with little fragment ions. Triethylamine (TEA) gave both [TEA+H]⁺ and [TEA−H]⁺.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>Because [M+H]⁺ was detected with little [M−H]⁺, which is usually detected as a major ion by vacuum surface ionization (VSI), it was concluded that [M+H]⁺ is formed by the proton transfer reaction between the protonated filament surface and the gas-phase analyte molecules approaching the solid surface. Namely, the heated metal filament acts as a Brønsted acid. This idea is supported by the APSI for TEA.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 12","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11927526/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143672936","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":"Determination of Free Amino Acid Concentrations in Bovine Plasma Using High-Pressure Liquid Chromatography With Electrospray Ionization Mass Spectrometry Detection","authors":"Laurie A. Reinhardt,&nbsp;Levi Svaren,&nbsp;Ritvik Marathe,&nbsp;Geoffrey I. Zanton,&nbsp;Michael L. Sullivan","doi":"10.1002/rcm.10027","DOIUrl":"https://doi.org/10.1002/rcm.10027","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Quantification of free amino acid concentrations in plasma has become an important tool in monitoring the health of dairy cows and health of their offspring under various management regimes, especially diet. Consequently, it was desirable to develop a robust, accurate, medium-throughput method to quantitate free amino acid concentrations in bovine plasma.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Bovine plasma was deproteinated with methanol and amino acids partially purified using cation exchange resin. Samples were then subjected to precolumn derivatization with phenyl isothiocyanate, followed by high-pressure liquid chromatography with positive electrospray ionization single quadrupole mass spectrometry detection for analysis. The corresponding ¹³C and ¹⁵N labeled amino acids (mass unit difference &gt; 3) were used as internal standards, while deuterium labeled standards were used for other metabolites.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>All 20 amino acids showed linear fits to their individual calibration curves (correlation coefficients &gt; 0.99) with concentration range of amino acids measured from 5 to 600 μM. Coefficient of variation (CV) values for the concentrations measured for all amino acids ranged from 2.0 to 6.7 for intraday aliquots and from 1.0 to 4.6 for interday aliquots with the exception of aspartic acid (11.1 and 12.6 for intraday and interday, respectively).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The use of a stable isotope labeled version of each amino acid analyte as internal standard added to plasma samples at the beginning of the procedure corrected for any losses, instrument variability, and chemistry of derivatization. Use of this method to quantify bovine plasma amino acids will allow better understanding of physiological processes underlying nutritional interventions in dairy production systems and may be more broadly applicable to ruminant and other animal production systems.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 11","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/rcm.10027","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143646079","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":"Dynamic Metabolite Profile Changes in Semen Ziziphi Spinosae During Ripening","authors":"Xi Tian,&nbsp;Sujun Zhang,&nbsp;Liqiang Gu,&nbsp;Wei Tian,&nbsp;Lingdi Liu,&nbsp;Qiang Li,&nbsp;Tao Jiang","doi":"10.1002/rcm.10024","DOIUrl":"https://doi.org/10.1002/rcm.10024","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>In traditional Chinese medicine, <i>Semen Ziziphi Spinosae</i> (SZS) is employed for alleviating conditions such as neurasthenia, sleep disorders, and anxiety. Its therapeutic effects are attributed to an abundance of biologically active compounds. The main objective of this study was the comparative profiling of SZS from different harvest times using a widely targeted metabolomics approach.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>First, UPLC-Q Trap-MS/MS was used for identification of metabolic profile. Then, multivariate statistical analysis and KEGG enrichment analysis were performed to screen out the differential metabolites and related metabolic pathways among different growth stages.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>In total, 466 metabolites were identified at three different growth and development stages (T1, T2, and T3) of SZS using UPLC-Q Trap-MS/MS, including 83 flavonoids, 80 phenolic acids, 67 amino acids and derivatives, 56 lipids, 39 nucleotides and derivatives, 38 organic acids, 1 quinone, 6 lignans and coumarins, 53 other metabolites, 10 tannins, 20 alkaloids, and 13 terpenoids. The result of clustering and PCA analyses showed that there was a great difference in metabolites between SZS at three growth stages. Differential metabolites in three comparison groups (T1 vs. T2, T2 vs. T3, and T1 vs. T3) were 195, 104, and 96, respectively. There were 29 common differential metabolites among the three different growth stages of SZS. The contents of important active ingredients (flavonoids and terpenoids) gradually increased during the T1, T2, and T3 stages, indicating that SZS harvested during T3 period was suitable for medicinal use. All the differential metabolites screened were enriched in 11 metabolic pathways, including glycerolipid metabolism, glycerophospholipid metabolism, phenylalanine metabolism, and phenylpropanoid biosynthesis pathway.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>This study provides a more comprehensive understanding of the dynamic changes in the metabolic profile of SZS, laying a foundation for subsequent development and utilization.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 11","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143646151","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 Long-Lasting, High-Stability Reactor System for Compound-Specific Carbon Isotope Analyses","authors":"Ewerton Santos,&nbsp;Bumsoo Kim,&nbsp;Rafael Tarozo,&nbsp;Sarah McGrath,&nbsp;Marcelo Alexandre,&nbsp;Yongsong Huang","doi":"10.1002/rcm.10020","DOIUrl":"https://doi.org/10.1002/rcm.10020","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Compound-specific carbon isotope analysis is an essential technique in environmental, geobiological, ecological, and forensic research. It involves the online conversion of organic compounds separated by gas chromatography (GC) into carbon dioxide before entering a gas source mass spectrometer for carbon isotopic analysis. However, current oxidation interfaces require frequent maintenance or reactor replacement, reducing efficiency and data quality and increasing costs. This study presents a modified oxidation interface to address these issues.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Our oxidation reactor system uses nickel and platinum wires as an oxidant with a constant oxygen flow controlled by an electronic pressure controller (EPC). This system eliminates the need for full-scale re-oxidation after initial activation and differs from systems using constant pressure control gauges that result in variable oxygen flow and carrier gas composition. We performed systematic comparisons of carbon isotope measurements for fatty acid methyl esters (FAMEs) and <i>n</i>-alkanes between our modified system and a commercial reactor system, and betweem systems that use constant pressure and constant flow oxygen supplies.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Our oxidation interface with a constant flow of oxygen significantly enhances the analytical precision and accuracy of carbon isotope values, as demonstrated by a consistent reduction in the standard deviation of δ¹³C values to below 0.3‰. Importantly, our system has undergone over 5000 injections extending over 9 months during our longest analytical cycle, with no maintenance or user intervention needed.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>Our novel reactor system with a constant flow supply of auxiliary oxygen gas to the reactor greatly outperforms the conventional reactor system in efficiency, precision, and accuracy. It is virtually maintenance-free and may be dubbed the “forever” reactor, resulting in greatly enhanced analytical efficiency and reduced cost. Our methodology can be implemented on commercial systems with straightforward modifications by users.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 11","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143622672","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 Approach to Assign Disulfide Connectivity for Ziconotide via Partial Reduction Without Alkylation","authors":"Peize Wu,&nbsp;Yuya Cheng,&nbsp;Weihua Wang,&nbsp;Ming Li","doi":"10.1002/rcm.10026","DOIUrl":"https://doi.org/10.1002/rcm.10026","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Disulfide bond, an important post-translational modification in peptides or proteins, is of great significance for stabilizing the three-dimensional spatial structure of peptides and proteins, maintaining correct folding conformation, and regulating biological activity. The medicinal peptide with unexpected disulfide connectivity might not have efficacy, even induce immunogenicity. Therefore, it is of importance to assign disulfide connectivity for a peptide.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>A relatively simple method based on partial reduction without alkylation was developed. For demonstration, ziconotide was chosen as a model establishing the method. After a partial reduction reaction by using tris(2-carboxyethyl)phosphine, the partially reduced ziconotide products containing one disulfide bond were analyzed by liquid chromatography tandem mass spectrometry. The information about the sequence uninvolved in the cyclic structure was obtained by tandem mass spectrometry, which reveals the connectivity of the disulfide bridges forming the cyclic structure.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Based on the results of only two partially reduced products, accurate connectivity of all disulfide bridges in ziconotide was obtained. Six cysteine moieties present in a ziconotide molecule form three disulfide bonds, which could produce 15 possible disulfide isoforms with different disulfide connectivities. The actual disulfide connectivity was easily identified using this novel method.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>A relatively simple method based on partial reduction without alkylation, followed by analysis with liquid chromatography–tandem mass spectrometry, was developed, assigning disulfide connectivity for a disulfide-rich peptide. This method is useful in the quality control of medicinal peptides with an extensive disulfide network.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 11","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143622700","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":"Rapid Proteomic Amelogenin Sex Estimation of Human and Cattle Remains Using Untargeted Evosep-timsTOF Mass Spectrometry","authors":"Charllotte Blacka,&nbsp;Adam Dowle,&nbsp;Mik Lisowski,&nbsp;Michelle Alexander,&nbsp;Jessica Hendy,&nbsp;Kirsty Penkman,&nbsp;Jackie Mosely","doi":"10.1002/rcm.10022","DOIUrl":"https://doi.org/10.1002/rcm.10022","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Sex estimation by analysis of amelogenin peptides in archaeological and fossil material has recently been gaining great traction within the fields of archaeology and palaeontology. Current widely used proteomic amelogenin sex estimation methods are hindered by relatively long mass spectrometric run times, or targeting peptides specific to human amelogenin proteins. Untargeted, high-throughput amelogenin sexing would be invaluable for a range of applications, from sex estimation of remains at mass grave sites to broadening the application of rapid amelogenin sexing to non-hominin species for husbandry and evolutionary studies.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>A new acid etch protocol followed by Evosep-LC-TIMS-TOF mass spectrometry is presented for amelogenin analysis, providing global peptide data through rapid mass spectrometric methods in under 20 min per sample (including sample preparation, mass spectrometric acquisition and data processing). This sampling protocol was developed on modern cattle (<i>Bos taurus</i>) teeth, before Evosep-timsTOF partial validation with archaeological cattle and human (<i>Homo sapiens</i>) teeth, demonstrating the potential of straightforward application of this rapid amelogenin sexing method to a range of taxa.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The rapid Evosep-LC-TIMS-TOF mass spectrometry methods gave comparable peptide counts to conventional long untargeted methods, while maintaining similar (or faster) acquisition times to those reported in methods targeting specific human amelogenin peptides. Implementation of the novel acid etch sampling approach also streamlined sample preparation without compromising peptide counts.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Rapid, untargeted Evosep-LC-TIMS-TOF mass spectrometry was successfully implemented in sex estimation of modern and archaeological material from <i>Bos taurus</i> and <i>Homo sapiens</i> teeth. This demonstrates an advancement in low-cost, high-throughput amelogenin sex estimation, for both human and zooarchaeological applications.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 11","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143595071","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":"Determination of KGa-1b and SHCa-1 Δ′17O and δ18O via Laser Fluorination of Lithium Fluoride Clay Pellets","authors":"Catherine A. Gagnon,&nbsp;Riley Havel,&nbsp;Jiquan Chen,&nbsp;Gavin Piccione,&nbsp;Daniel E. Ibarra","doi":"10.1002/rcm.10021","DOIUrl":"https://doi.org/10.1002/rcm.10021","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Stable oxygen isotope measurements in silicate clays, such as smectite and kaolinite, provide crucial information for understanding Earth's climate history and environmental changes. Despite a growing interest in the oxygen isotope analysis of silicate clays and clay-rich sediments, there lacks a consensus on the preparation and standardization of clay mineral samples. To improve the accuracy and interlaboratory comparisons of clay isotope measurements, especially those involving laser fluorination techniques, newly established kaolinite and smectite oxygen isotope standards are much needed.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>We employed conventional nickel bomb fluorination combined with dual-inlet isotope ratio mass spectrometry to establish precise δ¹⁸O and Δ′¹⁷O values for leached clay reference materials KGa-1b and SHCa-1, a kaolinite and a hectorite/smectite, respectively. We further measured leached KGa-1b and SHCa-1 pressed into pellets with a lithium fluoride as a binding agent for the laser fluorination method, allowing us to test the reproducibility between methods and utilize a standard laser chamber drift correction scheme.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The laser fluorination technique yielded highly precise and reproducible δ¹⁸O and Δ′¹⁷O measurements for the KGa-1b and SHCa-1, aligning with bomb values of δ¹⁸O. This confirms the method's reliability and comparability to conventional isotope measurement techniques while also stressing the importance of proper sample preparation and laser chamber drift corrections.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>This study demonstrates that laser fluorination is an effective method for accurately measuring the stable oxygen isotope composition of silicate clays or clay-rich sediments when corrected with known silicate clay standards. These methods offer a valuable methodology for future research and applications that will significantly improve our understanding of past climate and environmental conditions.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 11","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/rcm.10021","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143595072","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":"Using MALDI-FTICR Mass Spectrometry to Enhance ZooMS Identifications of Pleistocene Bone Fragments Showing Variable Collagen Preservation.","authors":"Pauline Raymond, Karen Ruebens, Fabrice Bray, Jean-Christophe Castel, Eugène Morin, Foni Le Brun-Ricalens, Jean-Guillaume Bordes, Christian Rolando, Jean-Jacques Hublin","doi":"10.1002/rcm.10019","DOIUrl":"https://doi.org/10.1002/rcm.10019","url":null,"abstract":"<p><strong>Rationale: </strong>Recent advances in high-throughput molecular analyses of collagen peptides, especially ZooMS (Zooarchaeology by Mass Spectrometry), have permitted breakthroughs in the analysis of archaeological material that is highly fragmented, a factor that hinders morphological identification. Despite these advances, the challenge of successfully analysing archaeological samples with poorer collagen preservation persists. This paper examines the potential of two mass analysers, TOF (Time of Flight) and FTICR (Fourier-transform ion cyclotron resonance), and addresses how they can be used to optimise the ZooMS workflow.</p><p><strong>Methods: </strong>Type 1 collagen (COL1) was extracted from 89 archaeological bones from the French Palaeolithic site of Le Piage (37-34 ka cal BP). Three ZooMS extraction protocols were applied, an acid-free buffer method (AmBic), offering rapid and less destructive analysis, and two methods of acid demineralisation (HCl and TFA) that provide higher peptide resolution. After analysing the specimens with MALDI-TOF and MALDI-FTICR, we used bottom-up and PRM (Parallel Reaction Monitoring) LC-MS/MS, and MALDI-CASI-FTICR (Continuous Accumulation of Selected Ions) to verify 26 ambiguous identifications.</p><p><strong>Results: </strong>Overall, 99% of the samples could be identified to at least family level, with the rate of identification and precision varying by method. Despite challenges in detecting specific biomarkers with MALDI-FTICR-especially peptide A (COL1ɑ2 978-990), which tends to be unstable and poorly ionised-the high resolution of this method allowed the successful identification of more degraded specimens, including burnt bones.</p><p><strong>Conclusions: </strong>Our work highlights the robustness of traditional MALDI-TOF ZooMS for retrieving collagen and for providing taxonomic identifications with low failure rates, features that are critical when processing large numbers of samples. MALDI-FTICR shows better potential when working with precious samples or degraded collagen. This study advances the analytical detection of peptides by optimising the ZooMS workflow and by tailoring it to specific archaeological contexts showing variation in degree of preservation.</p>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":" ","pages":"e10019"},"PeriodicalIF":1.8,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143584131","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":"Adapting Automatic Water Samplers for the Isotopic Study of Rainfall at High Temporal Resolution","authors":"Cécile Carton,&nbsp;Florent Barbecot,&nbsp;Jean-François Hélie,&nbsp;Viorel Horoi,&nbsp;Jean Birks","doi":"10.1002/rcm.10017","DOIUrl":"https://doi.org/10.1002/rcm.10017","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Stable water isotopes in precipitation are powerful tracers of atmospheric processes. Automatic rain samplers are valuable for high temporal resolution isotopic studies but building them from scratch requires significant financial and material resources. A commercial water autosampler has been modified to prevent post-sampling evaporation and to allow for intra-event precipitation sampling.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>New sampling bottles were created by reducing the original volume and opening area. Evaporation tests were carried out on different volumes of water for 72 h under laboratory conditions. These were used to determine the minimum amount of rain to collect to minimize the impact of isotopic fractionation by evaporation. The impact of the autosampler's air moisture saturation was also tested. Samples were analyzed by dual-inlet isotope ratio mass spectrometry and cavity ring-down spectroscopy.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>For samples larger than 10 mL, evaporative heavy isotope enrichment due to Rayleigh distillation remains negligible compared with the overall analytical uncertainty. Intentional saturation of the autosampler's atmosphere significantly reduces post-sampling evaporation but leads to equilibration of the samples with the added water. We have investigated the maximum time that samples must be left for this fractionation to remain negligible. Under these conditions, this autosampler is suitable for intra-event rainfall sampling for isotopic analysis.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>It is now possible to perform low-cost high-resolution precipitation sampling for isotopic analysis. The intentional air saturation of the sampler, which effectively prevents post-sampling evaporation, had never been proposed before. All instructions for modifying this sampler are now available in open access so the scientific community can easily repeat them.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"39 11","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/rcm.10017","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143565327","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}