Journal of the American Society for Mass Spectrometry最新文献

{"title":"Development of Electrostatic-to-Covalent Gas Phase Cross-linkers for Protein Structure Measurements by Mass Spectrometry.","authors":"Kacy L Black, Ian K Webb","doi":"10.1021/jasms.4c00363","DOIUrl":"10.1021/jasms.4c00363","url":null,"abstract":"<p><p>The benefits of native mass spectrometry have led to the extensive study of proteins inside mass spectrometers in the gas phase. The expansion of native mass spectrometry requires novel tools for gaining greater insights into protein structures. Herein, we introduce a new approach utilizing gas phase ion/ion reactions, where cross-linking reagents link unprotonated lysine residues, arginine residues, and N-termini with their protonated forms. We used three lengths of linkers, determining that different length cross-linkers resulted in different residues being cross-linked, as we have previously observed for electrostatic-to-electrostatic cross-linkers. However, this new method allows for the probing of both protonated and neutral lysine and arginine residues. Native mass spectrometry often produces fewer charges than protonatable sites, allowing access to a greater number of sites on proteins using an electrostatic-to-covalent cross-linking approach. In this report, we describe the reaction phenomenology and trends at reaction sites. We envision electrostatic-to-covalent cross-linking as a useful structural tool to provide complementary information to other native MS-based measurements such as collision cross section.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":" ","pages":"483-494"},"PeriodicalIF":3.1,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143397720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The 34th Sanibel Conference on Mass Spectrometry: Mass Spectrometry in Energy and the Environment.","authors":"Amy M McKenna, Janne Jänis","doi":"10.1021/jasms.5c00035","DOIUrl":"https://doi.org/10.1021/jasms.5c00035","url":null,"abstract":"","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":"36 3","pages":"446-449"},"PeriodicalIF":3.1,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143555582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative MALDI-TOF Mass Spectrometry of Star-Shaped Polylactides Based on Chromatographic Hyphenation.","authors":"Jana Falkenhagen, Mete-Sungur Dalgic, Steffen M Weidner","doi":"10.1021/jasms.4c00491","DOIUrl":"10.1021/jasms.4c00491","url":null,"abstract":"<p><p>The end groups of three- and four-arm star-shaped polylactides (PLA) with trimethylolpropane and pentaerythritol core structures were functionalized with acetic acid. Reaction products with different degrees of functionalization were analyzed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. Additional gradient elution liquid adsorption chromatography (GELAC) measurements were performed to determine the degree of functionalization. This technique enabled clear separation and sufficient quantification of the formed species. These chromatographic data could be used inversely to quantify mass spectrometric results, which are usually biased by the unknown ionization probabilities of different polymer end group structures. Our results showed that, in this particular case, the peak intensity in the MALDI-TOF mass spectra can be used to semiquantitatively determine the degree of functionalization in incompletely functionalized multiarm PLA.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":" ","pages":"613-621"},"PeriodicalIF":3.1,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11887435/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143063007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revisiting the Effect of Trypsin Digestion Buffers on Artificial Deamidation.","authors":"Emmajay Sutherland, Tim S Veth, Nicholas M Riley","doi":"10.1021/jasms.4c00389","DOIUrl":"10.1021/jasms.4c00389","url":null,"abstract":"<p><p>Deamidation of asparagine and glutamine residues occurs spontaneously, is influenced by pH, temperature, and incubation time, and can be accelerated by adjacent amino acid residues. Incubation conditions used for proteolytic digestion in bottom-up proteomic studies can induce significant deamidation that affects results, either knowingly or unknowingly. This has prompted studies into modifications to common trypsin digestion protocols to minimize chemical deamidation, including shorter incubation times and specific lysis buffers. Prior work suggested ammonium acetate at pH 6 to minimize chemical deamidation, but this buffer has compatibility issues with trypsin digestion and common assays (e.g., bicinchoninic acid assays). Here, we re-evaluated former comparisons of Tris-HCl, ammonium bicarbonate, and triethylammonium bicarbonate buffers for the amount of artificial, chemically induced deamidation generated in a standard bottom-up proteomics workflow, and we added an evaluation of three commonly used and biologically compatible buffers, HEPES (4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid), EPPS (3-[4-(2-Hydroxyethyl)piperazin-1-yl]propane-1-sulfonic acid), and PBS (phosphate buffered saline). Our findings show that HEPES exhibited the least amount of artificial deamidation and is a reasonable choice for general proteomic experiments, especially for studies considering N-glycosylation.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":" ","pages":"457-462"},"PeriodicalIF":3.1,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143063013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unexpected Artifact Formation in Mass Spectrometric Analysis of Aniline under Atmospheric-Pressure Chemical Ionization.","authors":"Ishira Samarasinghe, Julius Pavlov, Athula B Attygalle","doi":"10.1021/jasms.4c00286","DOIUrl":"10.1021/jasms.4c00286","url":null,"abstract":"<p><p>Atmospheric-pressure chemical ionization mass spectrometry (APCI-MS) is a widely used technique for the analysis of a diverse range of analytes. Under APCI conditions, a nonthermal plasma, rich in highly oxidative species such as H₂O₂, O₃, atomic O, and radicals such as HO^•, is created. These oxidants trigger unanticipated and often undesirable chemical reactions within the ion source. For example, when aniline was introduced into this environment, it initially underwent oxidative dimerization forming hydrazobenzene (<i>m</i>/<i>z</i> 185). However, with prolonged exposure, there was a marked increase in total ion abundance and the generation of additional artifact ions such as protonated azobenzene (<i>m</i>/<i>z</i> 183) and protonated azoxybenzene (<i>m</i>/<i>z</i> 199). The emergence of these artifacts was found to be highly dependent on the corona-current magnitude. Moreover, the desorption-gas temperature significantly influenced the rate of artifact generation. Recognizing and acknowledging the formation and presence of such artifacts in an ion source is paramount in conducting validated chemical analysis. The existence of artifacts can complicate mass spectral interpretation, potentially leading to erroneous conclusions and misinterpretations of both qualitative and quantitative data. Thus, understanding the intricacies of nonthermal plasma-driven artifact formation is critical for accurate analytical outcomes.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":" ","pages":"463-472"},"PeriodicalIF":3.1,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143187895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Use of TOFSim, a LabView-Based Time-of-Flight Mass Spectrometer Simulation, to Model Real Instrument Data.","authors":"Hannah M Palmer, Kevin G Owens","doi":"10.1021/jasms.4c00406","DOIUrl":"10.1021/jasms.4c00406","url":null,"abstract":"<p><p>It is demonstrated here that a recently published LabView-based time-of-flight mass spectrometer (TOFMS) simulation program (named TOFSim) can accurately simulate data collected on a commercial Bruker Autoflex III matrix-assisted laser desorption/ionization (MALDI) TOFMS instrument operating in linear mode. Once the instrument distances are determined by matching measured and simulated flight times, it is shown that both overall flight times and peak widths are reproduced for data collected under both focused and slightly defocused conditions. This work confirms that TOFSim can be used not just for training new instrument operators in the principles of TOFMS but, as demonstrated here, to show how changing the voltage applied to grid G1 in the source or the delayed extraction delay time affects the focusing properties of the instrument. In the future we expect that this will also allow users to perform \"what-if\" experiments to investigate scenarios which may be difficult or impossible to do in a real instrument.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":" ","pages":"534-541"},"PeriodicalIF":3.1,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11887436/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143363518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and Implementation of a Desorption Electro-flow Focusing Sprayer on an Orbitrap Mass Spectrometer for DESI Mass Spectrometry Imaging at High Spatial Resolution and at High Speed.","authors":"Carl Frederik Marc Hansen, Lukas Dobrovolskis, Christian Janfelt","doi":"10.1021/jasms.4c00341","DOIUrl":"10.1021/jasms.4c00341","url":null,"abstract":"<p><p>Since desorption electrospray ionization mass spectrometry (DESI-MS) was first presented in 2004, the fundamental design of the sprayer has undergone relatively minor modifications. This changed in 2022 when Takats and co-workers implemented the desorption electro-flow focusing (DEFFI) sprayer design by modifying the sprayer from a commercial DESI system, leading to significantly improved spatial resolution and robustness compared with the traditional DESI-MSI sprayer design. Here, we present the design of a new DEFFI sprayer that can be built from standard fittings and connectors in combination with an aluminum spray head that can be machined in most mechanic workshops. The new design represents a cost-efficient approach to improved DESI-MSI on mass spectrometers from all vendors, including high-resolution instruments such as Orbitraps and FT-ICR. The new DEFFI sprayer is demonstrated on a QExactive Orbitrap mass spectrometer, resulting in a massively improved ion yield compared with the classic DESI sprayer. The improved ion yield enables DESI-MSI at ion injection times down to 5 ms, allowing for DESI-MSI at a potentially very high speed. More importantly, the DEFFI sprayer delivers a more robust and focused spray, which is easier to use and requires less optimization. It provides high spatial resolution with limited effort compared with previous modifications of the traditional DESI design. Imaging of rat testis was performed at pixel sizes down to 12 μm, suggesting a spatial resolution of approximately 30 μm, which may have potential for further improvement.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":" ","pages":"473-482"},"PeriodicalIF":3.1,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142363834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improved LC-MS Detection of Opioids, Amphetamines, and Psychedelics Using TrEnDi.","authors":"Christian A Rosales, Noah A Lepinsky, Wondewossen Gebeyehu, Karl V Wasslen, Fraser Colquhoun, Benjamin B Warnes, Jasmine Chihabi, Jeffrey M Manthorpe, Jeffrey C Smith","doi":"10.1021/jasms.4c00382","DOIUrl":"10.1021/jasms.4c00382","url":null,"abstract":"<p><p>Substances of misuse are becoming increasingly difficult to analyze as unique methods of smuggling are adopted and due to the rapid emergence of new psychoactive substances, increasing the pool of compounds to characterize and identify. Technologies such as gas chromatography and liquid chromatography coupled to mass spectrometry (MS) represent the gold standard for accurate and robust analysis, with on-site ambient- and portable-MS systems providing rapid methods of drug screening and testing. For many samples containing residual analyte quantities, methods to improve sensitivity through chemical derivatization are critical for accurate determination. Herein, we demonstrate for the first time the use of trimethylation enhancement using diazomethane (TrEnDi) to improve the MS-based sensitivity of 13 different drugs of misuse. All analytes were successfully permethylated, with 11 demonstrating improved analytical characteristics from TrEnDi with MS sensitivity enhancements ranging from 1.2-fold to as high as 24.2-fold in the case of psilocybin, as well as increases in reversed-phase chromatographic retention for most species. Derivatization using ¹³C-isotopically labeled TrEnDi reagents were used to successfully resolve isobaric interference issues between three pairs of controlled substances. By using an unconventional aprotic solvent system for electrospray ionization, the benefit of a fixed-permanent positive charge was highlighted as TrEnDi-modified amphetamine was easily measured while unmodified was not detected. Finally, TrEnDi was employed to boost the sensitivity of morphine in a real urine matrix. Our results demonstrate a percent recovery of 103.1% and a sensitivity enhancement of 2.4-fold, demonstrating the versatility and applicability of TrEnDi to pre-existing analytical workflows for trace analysis.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":" ","pages":"514-523"},"PeriodicalIF":3.1,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143078410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a Bunching Ionizer for TOF Mass Spectrometers with Reduced Resources.","authors":"Oya Kawashima, Satoshi Kasahara, Yoshifumi Saito, Masafumi Hirahara, Kazushi Asamura, Shoichiro Yokota","doi":"10.1021/jasms.4c00436","DOIUrl":"10.1021/jasms.4c00436","url":null,"abstract":"<p><p>In some types of mass spectrometers, such as time-of-flight mass spectrometers (TOF-MSs), it is necessary to control pulsed beams of ions. This can be easily accomplished by applying a pulsed voltage to the pusher electrode while the ionizer is continuously flowing ions. This method is preferred for its simplicity, although the ion utilization efficiency is not optimized. Here we employed another pulse-control method with a higher ion utilization rate, which is to bunch ions and kick them out instead of letting them stream. The benefit of this method is that higher sensitivity can be achieved; since the start of new ions cannot be allowed during TOF separation, it is highly advantageous to bunch ions that would otherwise be unusable. In this study, we used analytical and numerical methods to design a new bunching ionizer with reduced resources, adopting the principle of the electrostatic ion beam trap. The test model experimentally demonstrated the bunching performance with respect to the sample gas density and ion bunching time using gas samples and electron impact ionization. We also conducted an experiment connecting the newly developed bunching ionizer with a miniature TOF-MS. As a result, the sensitivity was improved by an order of magnitude compared to the case using a nonbunching ionizer. Since the device is capable of bunching ions with low voltage and power consumption, it will be possible to find applications in portable mass spectrometers with reduced resources.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":" ","pages":"553-564"},"PeriodicalIF":3.1,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143389830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Highly Efficient and Automated Magnetic Bead Extraction Method Overcomes the Matrix Effect in LC–MS/MS Analysis of Human Serum Steroid Hormones","authors":"Xiaoyi Yi,&nbsp;Xiaojing Huang,&nbsp;Yufeng Xiong and Yingsong Wu*,&nbsp;","doi":"10.1021/jasms.4c0033810.1021/jasms.4c00338","DOIUrl":"https://doi.org/10.1021/jasms.4c00338https://doi.org/10.1021/jasms.4c00338","url":null,"abstract":"<p >Profiling of steroid hormones is incredibly valuable in clinical settings for diagnosing endocrine disorders. However, the presence of matrix effects and labor-intensive manual work in LC–MS/MS analysis has hindered its routine application. In the present study, a highly efficient and automated magnetic bead extraction method was developed to address matrix effects and quantitatively profile 15 steroid hormones in human serum. Octadecyl (C18) and <i>N</i>-vinylpyrrolidone divinylbenzene (HLB) modified magnetic beads were compared for enriching steroids from human serum. Following enrichment, the beads were separated using a magnetic field; the matrix was cleaned, and the steroid hormones were eluted from the beads for LC–MS/MS analysis. This entire process of enrichment, cleanup, and elution was conducted automatically, making it simple, fast, and cost-effective. The results indicated that steroid hormones could be selectively enriched from human serum in just 1 min using C18 magnetic beads. The absolute matrix effect, evaluated as the relative response between human serum matrix and methanol solution, ranged from 89.2% to 113.1% for low levels, from 82.3% to 112.0% for medium levels, and from 91.7% to 111.0% for high levels. The intrabatch coefficients of variation (CVs) and interbatch CVs were between 3.1% and 13.4% and between 3.0% and 13.7%, respectively. Recoveries were between 87.6% and 114.3% for low levels, 94.0% and 105.0% for medium levels, and 91.9% and 111.7% for high levels. The clinical application was demonstrated by profiling steroid hormones in 160 pregnant women at various gestational weeks. The results suggested that the automated magnetic bead extraction method for LC–MS/MS could effectively address matrix effects in profiling steroid hormones. To our knowledge, this is the first automated magnetic bead extraction method for LC–MS/MS profiling of steroid hormones in clinical practice.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":"36 4","pages":"699–712 699–712"},"PeriodicalIF":3.1,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}