Rapid Communications in Mass Spectrometry最新文献

{"title":"Exploring the Mechanism of Zhigancao Decoction in the Treatment of Chronic Heart Failure via Modulation of Oxidative Stress","authors":"Ze Luo,&nbsp;Yan Huang,&nbsp;Yonggang Tian,&nbsp;Shi Huang,&nbsp;Fangqiong Li","doi":"10.1002/rcm.70177","DOIUrl":"https://doi.org/10.1002/rcm.70177","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Zhigancao decoction has shown therapeutic potential in the management of chronic heart failure (CHF); however, the molecular mechanisms underlying its pharmacological effects remain incompletely understood. This study aimed to investigate its potential mechanisms, with a particular focus on oxidative stress-related pathways.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>The chemical profile of Zhigancao decoction was characterized by LC–MS/MS, and putative targets were predicted using SwissTargetPrediction. A protein–protein interaction (PPI) network was established using the STRING database and Cytoscape software, followed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Differentially expressed genes from two GEO datasets (GSE9128 and GSE84796) were integrated with reactive oxygen species (ROS)-related genes to identify candidate targets. Network pharmacology and molecular docking were subsequently performed to investigate compound–target interactions.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>A total of 66 chemical constituents and 818 putative targets were characterized and collected, respectively. Among these targets, MMP9 emerged as a central candidate associated with the therapeutic effects of Zhigancao decoction. GO and KEGG enrichment analyses demonstrated that the core targets were significantly enriched in oxidative stress-related pathways, inflammatory signaling cascades, and cell fate regulatory pathways. Computational deconvolution of bulk transcriptomic data suggested marked alterations in the estimated immune cell composition of the CHF microenvironment. Network pharmacology analysis further indicated that multiple chemical constituents of Zhigancao decoction converge on MMP9 and its associated pathways. Molecular docking analysis demonstrated favorable binding affinities between 10 representative compounds and MMP9, with binding energies below −7.0 kcal/mol.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>In silico predictions suggest that Zhigancao decoction may exert potential therapeutic effects against CHF through computationally predicted targeting of MMP9 and associated oxidative stress- and immune-related pathways. These computational findings provide a theoretical foundation for future experimental investigations into the mechanisms of Zhigancao decoction in CHF, though clinical application would require confirmation through rigorous in vivo and clinical studies.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"40 22","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148942967","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":"Advances in the Design and Functionality of a Compact Multi-Reflecting Time-of-Flight Mass Spectrometer","authors":"Jason Wildgoose,&nbsp;Samantha Ferries,&nbsp;Lee A. Gethings,&nbsp;Matthew E. Daly,&nbsp;Martin E. Palmer,&nbsp;Richard Lock,&nbsp;Johannes P. C. Vissers,&nbsp;James I. Langridge","doi":"10.1002/rcm.70173","DOIUrl":"10.1002/rcm.70173","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>High-resolution mass spectrometry is routinely used for the analysis of complex samples in pharmaceutical, environmental, and omics related studies. Such applications demand instrumentation to be capable of combining sub-ppm mass accuracy, high resolving power, rapid full <i>m/z</i> range acquisition over a wide dynamic range.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Achieving the above requirements places constraints on analyzer design and performance. Multi-reflecting time-of-flight (MRT) based analyzers have previously been reported as a means of significantly extending the effective flight path in compact TOF designs. Here, further instrument and functionality advances in a compact MRT mass spectrometer design are described.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The impact of these enhancements was assessed for targeted and non-targeted omics applications, examining the impact of acquisition speed on resolving power, dynamic range including limits of quantitation, and quantitative precision.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>The results obtained characterize the performance of the enhanced design features of a compact MRT mass spectrometer. Operation at elevated acquisition rates up to 200 Hz was observed without loss in resolving power, isotopic ratio accuracy or quantitative precision.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"40 22","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13556519/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148910264","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":"Exploratory Measurements of Singly Substituted and Clumped Isotopologues in Iodate Using Electrospray Ionization Mass Spectrometry","authors":"Jamie Lucarelli,&nbsp;Amanda R. Bubas,&nbsp;Richard M Cox,&nbsp;Sophie B. Lehmann,&nbsp;Aradhna Tripati,&nbsp;Mark Engelmann,&nbsp;Elise R. Conte","doi":"10.1002/rcm.70161","DOIUrl":"10.1002/rcm.70161","url":null,"abstract":"&lt;div&gt;\u0000 \u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Rationale&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;Clumped isotope geochemistry can reveal the temperatures and chemical pathways at which molecules form, but it remains unexplored for most inorganic systems. Iodate (IO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;−&lt;/sup&gt;) is central to ocean and atmospheric iodine cycling and to tracking radioactive iodine from nuclear activity. Here, we report the first exploratory investigation into the feasibility of measuring bulk and clumped isotopologues in iodate using electrospray ionization mass spectrometry (ESI-MS).&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Methods&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;Sodium iodate was dissolved in either deionized water or 97% H&lt;sub&gt;2&lt;/sub&gt;&lt;sup&gt;18&lt;/sup&gt;O. Two sample sets systematically varied the H&lt;sub&gt;2&lt;/sub&gt;&lt;sup&gt;18&lt;/sup&gt;O fraction of the spray solvent from 0% to 97%. Samples were infused into a Thermo Scientific TSQ Quantum Access MAX triple-quadrupole mass spectrometer with an atmospheric pressure ionization source operated in negative-ion scan mode. Spectra were acquired over &lt;i&gt;m/z&lt;/i&gt; 110–190 and averaged across 25 scans.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Results&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;The singly substituted isotopologue (&lt;sup&gt;127&lt;/sup&gt;I&lt;sup&gt;16&lt;/sup&gt;O&lt;sub&gt;2&lt;/sub&gt;&lt;sup&gt;18&lt;/sup&gt;O&lt;sup&gt;−&lt;/sup&gt;, &lt;i&gt;m/z&lt;/i&gt; 177), clumped isotopologues (&lt;sup&gt;127&lt;/sup&gt;I&lt;sup&gt;16&lt;/sup&gt;O&lt;sup&gt;18&lt;/sup&gt;O&lt;sub&gt;2&lt;/sub&gt;&lt;sup&gt;−&lt;/sup&gt;, &lt;i&gt;m/z&lt;/i&gt; 179; &lt;sup&gt;127&lt;/sup&gt;I&lt;sup&gt;18&lt;/sup&gt;O&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;−&lt;/sup&gt;, &lt;i&gt;m/z&lt;/i&gt; 181), and isotopologue distributions were resolved in IO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;−&lt;/sup&gt;. Relative isotopologue abundances shifted monotonically with solvent &lt;sup&gt;18&lt;/sup&gt;O content; &lt;sup&gt;127&lt;/sup&gt;I&lt;sup&gt;18&lt;/sup&gt;O&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;−&lt;/sup&gt; increased from 0% to 56% across the enrichment range. In the natural abundance sample, measured isotopologue abundances matched the values predicted for a stochastic (random) isotope distribution, confirming that the instrument is sampling the natural isotopologue distribution without significant bias. We also report isotopologue distributions for IO&lt;sup&gt;−&lt;/sup&gt; and IO&lt;sub&gt;2&lt;/sub&gt;&lt;sup&gt;−&lt;/sup&gt;, which exhibit isotopic trends similar to those observed for IO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;−&lt;/sup&gt;.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Conclusions&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;These first measurements of isotopologues in IO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;−&lt;/sup&gt; establish ESI-MS as an accessible platform for isotopic analysis of inorganic oxyanions under enriched conditions. We discuss the thermodynamic basis for equilibrium clumping in IO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;−&lt;/sup&gt;, the analytical requirements for extending these enriched sample measurements to natural abundance clumped isotope thermometry, and the potential applications of this s","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"40 22","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13551374/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148904610","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":"Chemical Profiling by UHPLC–MS/MS and In Vitro Antioxidant, Antimicrobial, and Cytotoxic Properties of Lepidoceras peruvianum Kuijt Leaves and Fruits","authors":"Marco Rolando Aronés Jara,&nbsp;Kirianova Godoy Bautista,&nbsp;Freshsia Ingrid Ortiz Pérez,&nbsp;Edgar Cárdenas Landeo,&nbsp;Edith Eveling Conislla Cáceres,&nbsp;Hugo Roberto Luna Molero,&nbsp;Juan Clímaco Paniagua Segovia,&nbsp;Jaeson Santos Calla Choque,&nbsp;Anas Rashid,&nbsp;María Segunda Aurora Prado","doi":"10.1002/rcm.70172","DOIUrl":"10.1002/rcm.70172","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p><i>Lepidoceras peruvianum</i> Kuijt is an understudied hemiparasitic species endemic to the Peruvian Andes that lacks comprehensive phytochemical characterization. Investigating its metabolome is important for understanding its chemotaxonomic relevance and potential as a source of bioactive compounds.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Leaves and fruits of <i>L. peruvianum</i> were subjected to untargeted metabolomic profiling using high-resolution UHPLC–ESI-Orbitrap-MS/MS in positive and negative ionization modes. Metabolites were annotated based on accurate mass measurements, isotopic patterns, collision-induced dissociation (CID) fragmentation data, and spectral matching with the Global Natural Products Social Molecular Networking (GNPS), METLIN, and MassBank databases. Structural elucidation employed diagnostic fragmentation pathways, including retro-Diels–Alder (RDA), heterocyclic ring fission (HRF), quinone methide (QM), and benzofuran-forming (BFF) cleavages. Antioxidant activity was evaluated using DPPH●, ABTS●+, and FRAP assays, while antimicrobial activity and toxicity were assessed through antibacterial testing and the <i>Artemia salina</i> lethality assay.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Leaves contained 34 metabolites, mainly flavan-3-ols, proanthocyanidins, flavonols, lignans, and isoquinoline alkaloids, whereas fruits were characterized by anthocyanins, organic acids, and polar lipids. Total phenolic content was higher in leaves (292.4 mg GAE/g) than in fruits (216.8 mg GAE/g), corresponding to stronger antioxidant activity. Leaves extracts exhibited greater antibacterial activity against <i>Staphylococcus aureus</i>, while fruit extracts showed stronger effects against Gram-negative bacteria. LC₅₀ values in the <i>A. salina</i> assay were 181.8 μg/mL for leaves and 475.9 μg/mL for fruits.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>This study provides the first comprehensive metabolomic characterization of <i>L. peruvianum</i>, revealing organ-specific chemical diversity and notable bioactive properties. The findings demonstrate the utility of HRMS/MS fragmentation analysis for metabolite annotation and identify this endemic species as a promising source of bioactive natural products.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"40 22","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148872399","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":"Nitrogen and Sulfur Assimilation in Fish Otoliths Evaluated by Stable Isotope Labeling and NanoSIMS Analysis","authors":"Hao-Shu Hsu,&nbsp;Silver Sung-Yun Hsiao,&nbsp;Pei-Ling Wang,&nbsp;Yoshiyuki Iizuka,&nbsp;Tzu-Yen Liu,&nbsp;Yung-Che Tseng,&nbsp;Jen-Chieh Shiao","doi":"10.1002/rcm.70174","DOIUrl":"10.1002/rcm.70174","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Stable nitrogen (δ¹⁵N) and sulfur (δ³⁴S) isotopes within the metabolically inert organic matrix of teleost otoliths provide high-fidelity archives for reconstructing animal life histories. However, low organic content limits the spatial resolution of conventional bulk isotopic analysis, leaving biomineralization kinetics and the temporal integration of these dietary signals poorly quantified. We utilized nanoscale secondary ion mass spectrometry (NanoSIMS) to overcome these limitations and determine intracrystalline isotopic dynamics.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Isotopic pulses were established by feeding juvenile Mozambique tilapia (<i>Oreochromis mossambicus</i>) ¹⁵N-enriched algae and diets supplemented with L-methionine-³⁴S, utilizing Alizarin Red S fluorescent marking for precise temporal referencing. High-resolution and in situ NanoSIMS analysis was applied to quantify the temporal distribution of the labeling signals within the otolith organic matrix. A first-order kinetic model was used to estimate isotopic dynamics half-lives (<i>t</i>_50%).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>NanoSIMS analysis revealed rapid isotopic changes across both assimilation and depuration phases (<i>t</i>_50% = 0.5–13.9 days). Both δ¹⁵N and δ³⁴S exhibited statistically indistinguishable kinetics, reflecting synchronized metabolic routing where dietary signals are deposited directly into the otolith without being buffered by internal tissue reserves. Crucially, the dietary matrix modulated assimilation; despite comparable dietary δ³⁴S proportions, otolith sulfur incorporation and signal attenuation were significantly faster in fish fed algae-based diets than in those fed eel-meal-based diets. This demonstrates the preferential utilization of exogenous labeled methionine when the base diet is naturally deficient in this essential amino acid.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>High-resolution NanoSIMS profiling demonstrates that the otolith organic matrix archives dietary signals governed by rapid assimilation pathways rather than strict thermodynamic equilibrium. This analytical approach establishes a crucial mechanistic basis and experimental framework for utilizing intracrystalline organic isotopes as precise indicators in trophic ecology.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"40 22","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148862959","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 Vonoprazan Fumarate by HPLC and Characterisation of Its Degradation Products Using LC-QTOF-MS/MS","authors":"Nehal Bhatt,&nbsp;Devendra Sonaje,&nbsp;Gananadhamu Samanthula","doi":"10.1002/rcm.70170","DOIUrl":"10.1002/rcm.70170","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Acid-related disorders, including gastro-oesophageal reflux disease (GERD), peptic ulcers and <i>Helicobacter pylori</i> infection, affect millions worldwide. Vonoprazan fumarate, a potassium-competitive acid blocker, provides rapid and sustained acid suppression. Understanding its degradation behaviour is essential for ensuring drug stability, supporting formulation development and guiding quality control.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Vonoprazan fumarate was subjected to acidic and basic hydrolysis, oxidation, thermal and photolytic stress to evaluate its degradation behaviour. Degradation products were separated by reversed-phase high-performance liquid chromatography (HPLC) using a gradient program optimised for mobile-phase composition and flow rate, thereby enabling the chromatographic resolution of closely eluting degradation products. Structural characterisation was performed using liquid chromatography–quadrupole time-of-flight tandem mass spectrometry (LC-QTOF-MS/MS) based on accurate-mass measurements and diagnostic MS/MS dissociation patterns. The method was validated for linearity, precision, accuracy, selectivity and robustness.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Nine degradation products were detected under stress conditions: Basic hydrolysis yielded degradation product (DP)-1 and DP-8; acidic stress produced DP-1, DP-2 and DP-4; oxidation generated DP-1, DP-2, DP-7 and DP-8; and photolysis formed DP-1 to DP-6, DP-8 and DP-9. Three degradation products exhibited identical protonated molecules and closely comparable MS/MS dissociation patterns to the parent drug but differed in chromatographic retention times, with their relative distribution varying in solution- and solid-state upon UV exposure.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>This study provides a comprehensive evaluation of the forced degradation behaviour of vonoprazan fumarate by RP-HPLC and characterisation of its degradation products using LC-QTOF-MS/MS, providing insights into its degradation pathways and supporting stability assessment. Comparative solution- and solid-state photostability studies revealed distinct degradation profiles, providing further insight into the photodegradation behaviour of vonoprazan fumarate.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"40 22","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148862868","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":"Profiling and Identification of Novel Tiletamine Metabolites in Human Urine and Hair by Liquid Chromatography Coupled With Quadrupole-Orbitrap Mass Spectrometry","authors":"Shiyang Qin,&nbsp;Guibin Bi,&nbsp;Yuanfeng Wang,&nbsp;Bing Liu,&nbsp;Zhenjia Cui,&nbsp;Xuxiao Zhao,&nbsp;Xiaopei Wu,&nbsp;Jing Jing,&nbsp;Jianghai Lu","doi":"10.1002/rcm.70171","DOIUrl":"10.1002/rcm.70171","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Tiletamine, an animal tranquilizer increasingly misused by humans, lacks comprehensive metabolic characterization in authentic biological matrices. To date, tiletamine phase II metabolism remains poorly characterized. This study investigated the metabolic fate of tiletamine in human urine and hair by identifying novel metabolites and elucidating biotransformation pathways relevant to forensic toxicological monitoring.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Authentic human urine (<i>n</i> = 3) and hair (<i>n</i> = 2) samples from individuals with documented tiletamine exposure were analyzed using liquid chromatography coupled with Q Extractive HF hybrid quadrupole-Orbitrap high-resolution mass spectrometry (LC-QE-HF-MS). Metabolites were detected and identified based on full-scan MS and data-dependent MS/MS (ddMS²) fragmentation patterns. Structural elucidation, including the assignment of hydroxylation sites, was achieved through a diagnostic fragment ion analysis.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>A total of 14 urinary metabolites were identified, 11 of which (4 phase I and 7 phase II) were previously unreported. Hydroxylation was the predominant phase I process, whereas glucuronidation predominated among phase II reactions. Methylation and glucuronidation were identified as previously unreported metabolic pathways. In hair samples, tiletamine and four metabolites, including three reduced metabolites and T1, were identified for the first time. In addition, three metabolic transformations, namely, reduction, hydroxylation, and methylation, were newly identified in this matrix. Notably, T1 exhibited substantially higher signal intensities than all other metabolites across all urine samples.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>This study substantially expands the known urinary metabolome by identifying novel phase I and II metabolites. The consistently high abundance of T1 in urine suggests that it is a promising urinary biomarker for monitoring tiletamine use. These findings broaden the range of analytical targets available for toxicological screening and confirmational analysis, thereby improving the detection and monitoring of tiletamine exposure.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"40 22","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148862904","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":"Liquid Atmospheric Pressure MALDI (LAP-MALDI) Mass Spectrometry: A Versatile Tool for the Characterization of Synthetic Polymers.","authors":"Agata E Kowalczyk, Jeffery Brown, Michael Morris, Rainer Cramer","doi":"10.1002/rcm.70102","DOIUrl":"10.1002/rcm.70102","url":null,"abstract":"<p><strong>Rationale: </strong>Liquid atmospheric pressure matrix-assisted laser desorption/ionization (LAP-MALDI) mass spectrometry (MS) has previously been applied to the analysis of biopolymers such as peptides, proteins, and DNA, producing ESI-like multiply charged analyte ions. In this study, LAP-MALDI MS has been investigated for the analysis of synthetic polymers for the first time.</p><p><strong>Methods: </strong>A LAP-MALDI source was interfaced with a Q-TOF mass spectrometer. The study investigated synthetic polymer standards, including polyethylene glycol (PEG), polypropylene glycol (PPG), polyacrylic acid (PAA), and polystyrene (PS) of different sizes in positive and negative ionization modes with and without ion mobility spectrometry (IMS). The acquired data were compared to ESI MS data using the same polymer standards and instrument but with a standard ESI source.</p><p><strong>Results: </strong>LAP-MALDI MS enables the detection of singly and predominantly multiply charged ions with high ion signal stability (< 10% RSD), though with lower charge states than ESI MS. Its flexible sample preparation and ion source setup allow for the controlled manipulation of charge states. Common salts facilitate ionization by metal cation adduct formation and improve detection of PEG, PPG, and PS. PAA was efficiently detected in negative ion mode by deprotonation, and PS required a silver salt for ionization. IMS provides an additional dimension in separation and manipulating charge state distributions, and its data obtained for PEG corroborate previously published ESI IMS results.</p><p><strong>Conclusions: </strong>LAP-MALDI MS provides a rapid, less labor-intensive, and reagent-efficient way for the analysis of synthetic polymers and produces stable ion signals in both positive and negative ion modes. The source enables the detection of singly and multiply charged ions, with the flexibility to manipulate charge states over a wide range. LAP-MALDI MS tolerates diverse solvent compositions and offers a versatile platform for high-throughput polymer structural analysis, including MS/MS analysis that can replace or complement standard polymer analysis tools.</p>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"40 16","pages":"e70102"},"PeriodicalIF":1.8,"publicationDate":"2026-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13173394/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147924984","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":"Gating Modes in Ion Mobility-Mass Spectrometry: Principles, Advances, and Coupling With Mass Analyzers","authors":"Tao Li,&nbsp;Shuichen Xiong,&nbsp;Ting Jiang,&nbsp;Wei Xu","doi":"10.1002/rcm.70169","DOIUrl":"https://doi.org/10.1002/rcm.70169","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>Ion mobility–mass spectrometry (IM-MS) provides an additional gas-phase separation dimension and complementary structural and conformational information through collision cross-section (CCS) values. Its analytical performance depends not only on mobility resolving power but also on temporal coordination among ion generation, mobility separation, ion transfer, and mass spectrometric acquisition.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>This review examines the principles and recent developments of serial gating modes, including single-gate pulsed injection and dual-gate operation, and multiplexed gating modes, including sequence-encoded, correlation-based, and Fourier transform approaches. These modes are compared in terms of gate duty cycle, ion utilization efficiency, mobility resolving power, sensitivity, acquisition efficiency, reconstruction reliability, and compatibility with mass analyzers having different acquisition timescales.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The comparison shows that serial gating provides direct acquisition and well-defined timing relationships, whereas its ion utilization depends strongly on upstream accumulation and the sampling strategy. Multiplexed gating generally increases the gate-open fraction and admits a larger fraction of the ion beam but requires reliable reconstruction. High-resolution demultiplexing can increase the effective mobility resolving power of sequence-encoded data. Temporal matching requirements differ between fast, continuously acquiring mass analyzers and analyzers with longer or temporally selective acquisition cycles.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Gate duty cycle and ion utilization efficiency are related but distinct performance metrics, and no single gating mode is optimal for all IM-MS platforms. Gating strategies should therefore be selected and optimized according to the analytical objective, ion availability, required mobility resolving power, mass-analyzer acquisition timescale, and tolerance for reconstruction artefacts.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"40 22","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148823394","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":"Mass Spectrometry for Semiquantitative Analysis of Thermal Decomposition: A Methodological Case Study on the Pyrolysis of a (CH3)SiO1.5 Hybrid Gel","authors":"Renzo Campostrini,&nbsp;Graziano Guella,&nbsp;Peter Kroll,&nbsp;Maurizio Grigiante","doi":"10.1002/rcm.70150","DOIUrl":"10.1002/rcm.70150","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Rationale</h3>\u0000 \u0000 <p>The thermal decomposition of (CH₃)SiO_1.5 gels has been systematically investigated by TG-MS, revealing a complex temperature-dependent evolution of gaseous species. This work demonstrates that the TG-MS analysis, coupled with rigorous data processing, allows to set up an insightful methodology to evolve from a qualitative monitoring tool into a quantitative approach, opening new avenues for thermal and compositional analysis.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>By combining ion current integration with fragmentation pattern analysis, a semiquantitative determination of the gas-phase composition was achieved, enabling correlation between individual species release, reaction mechanisms, and total mass loss.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The stoichiometric analysis of the evolved products has allowed the reconstruction of the gel's initial chemical composition solely from MS data, offering a powerful alternative to conventional structural characterization. The excellent agreement between measured (17.28%) and MS-derived (17.24%) mass loss confirms the reliability of the approach, considering also that the thermal decomposition of the methylsiloxane hybrid gel investigated is representative of a complex system generating numerous overlapping volatile species.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The proposed study investigates the potentialities of the TG-MS analysis in setting up a powerful tool for the study of thermal decomposition of hybrid organic–inorganic materials. The proposed approach opens new perspectives for thermal process investigations and for the compositional analysis of materials where conventional characterization methods are limited or unavailable.</p>\u0000 </section>\u0000 </div>","PeriodicalId":225,"journal":{"name":"Rapid Communications in Mass Spectrometry","volume":"40 21","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/rcm.70150","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148811585","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}