Joshua A Roberts, Angela S Radnoff, Aleksandra Bushueva, Jocelyn A Menard, Karl V Wasslen, Meaghan Harley, Jeffrey M Manthorpe, Jeffrey C Smith
{"title":"Mobile Phase Contaminants Affect Neutral Lipid Analysis in LC-MS-Based Lipidomics Studies.","authors":"Joshua A Roberts, Angela S Radnoff, Aleksandra Bushueva, Jocelyn A Menard, Karl V Wasslen, Meaghan Harley, Jeffrey M Manthorpe, Jeffrey C Smith","doi":"10.1021/jasms.4c00320","DOIUrl":"10.1021/jasms.4c00320","url":null,"abstract":"<p><p>Lipidomics is a well-established field, enabled by modern liquid chromatography mass spectrometry (LC-MS) technology, rapidly generating large amounts of data. Lipid extracts derived from biological samples are complex, and most spectral features in LC-MS lipidomics data sets remain unidentified. In-depth analyses of commercial triacylglycerol, diacylglycerol, and cholesterol ester standards revealed the expected ammoniated and sodiated ions as well as five additional unidentified higher mass peaks with relatively high intensities. The identities and origin of these unknown peaks were investigated by modifying the chromatographic mobile-phase components and LC-MS source parameters. Tandem MS (MS/MS) of each unknown adduct peak yielded no lipid structural information, producing only an intense ion of the adducted species. The unknown adducts were identified as low-mass contaminants originating from methanol and isopropanol in the mobile phase. Each contaminant was determined to be an alkylated amine species using their monoisotopic masses to calculate molecular formulas. Analysis of bovine liver extract identified 33 neutral lipids with an additional 73 alkyl amine adducts. Analysis of LC-MS-grade methanol and isopropanol from different vendors revealed substantial alkylated amine contamination in one out of three different brands that were tested. Substituting solvents for ones with lower levels of alkyl amine contamination increased lipid annotations by 36.5% or 27.4%, depending on the vendor, and resulted in >2.5-fold increases in peak area for neutral lipid species without affecting polar lipid analysis. These findings demonstrate the importance of solvent selection and disclosure for lipidomics protocols and highlight some of the major challenges when comparing data between experiments.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142379825","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}
Sarah Trimpin, Frank S Yenchick, Chuping Lee, Khoa Hoang, Milan Pophristic, Santosh Karki, Darrell D Marshall, I-Chung Lu, Corinne A Lutomski, Tarick J El-Baba, Beixi Wang, Vincent S Pagnotti, Anil K Meher, Shubhashis Chakrabarty, Lorelei F Imperial, Sara Madarshahian, Alicia L Richards, Christopher B Lietz, Abigail Moreno-Pedraza, Samantha M Leach, Stephen C Gibson, Efstathios A Elia, Shameemah M Thawoos, Daniel W Woodall, Dean R Jarois, Eric T J Davis, Guochao Liao, Nisansala S Muthunayake, McKenna J Redding, Christian A Reynolds, Thilani M Anthony, Sashiprabha M Vithanarachchi, Paul DeMent, Adeleye O Adewale, Lu Yan, James Wager-Miller, Young-Hoon Ahn, Thomas H Sanderson, Karin Przyklenk, Miriam L Greenberg, Arthur G Suits, Matthew J Allen, Srinivas B Narayan, Joseph A Caruso, Paul M Stemmer, Hien M Nguyen, Steffen M Weidner, Kevin J Rackers, Ana Djuric, Vladimir Shulaev, Tamara L Hendrickson, Christine S Chow, Mary Kay H Pflum, Scott M Grayson, Vladislav V Lobodin, Zhongwu Guo, Chi-Kung Ni, J Michael Walker, Ken Mackie, Ellen D Inutan, Charles N McEwen
{"title":"New Processes for Ionizing Nonvolatile Compounds in Mass Spectrometry: The Road of Discovery to Current State-of-the-Art.","authors":"Sarah Trimpin, Frank S Yenchick, Chuping Lee, Khoa Hoang, Milan Pophristic, Santosh Karki, Darrell D Marshall, I-Chung Lu, Corinne A Lutomski, Tarick J El-Baba, Beixi Wang, Vincent S Pagnotti, Anil K Meher, Shubhashis Chakrabarty, Lorelei F Imperial, Sara Madarshahian, Alicia L Richards, Christopher B Lietz, Abigail Moreno-Pedraza, Samantha M Leach, Stephen C Gibson, Efstathios A Elia, Shameemah M Thawoos, Daniel W Woodall, Dean R Jarois, Eric T J Davis, Guochao Liao, Nisansala S Muthunayake, McKenna J Redding, Christian A Reynolds, Thilani M Anthony, Sashiprabha M Vithanarachchi, Paul DeMent, Adeleye O Adewale, Lu Yan, James Wager-Miller, Young-Hoon Ahn, Thomas H Sanderson, Karin Przyklenk, Miriam L Greenberg, Arthur G Suits, Matthew J Allen, Srinivas B Narayan, Joseph A Caruso, Paul M Stemmer, Hien M Nguyen, Steffen M Weidner, Kevin J Rackers, Ana Djuric, Vladimir Shulaev, Tamara L Hendrickson, Christine S Chow, Mary Kay H Pflum, Scott M Grayson, Vladislav V Lobodin, Zhongwu Guo, Chi-Kung Ni, J Michael Walker, Ken Mackie, Ellen D Inutan, Charles N McEwen","doi":"10.1021/jasms.3c00122","DOIUrl":"https://doi.org/10.1021/jasms.3c00122","url":null,"abstract":"<p><p>This <i>Perspective</i> covers discovery and mechanistic aspects as well as initial applications of novel ionization processes for use in mass spectrometry that guided us in a series of subsequent discoveries, instrument developments, and commercialization. <i>Vacuum</i> matrix-assisted ionization on an intermediate pressure matrix-assisted laser desorption/ionization source <i>without</i> the use of a laser, high voltages, or any other added energy was simply unbelievable, at first. Individually and as a whole, the various discoveries and inventions started to paint, <i>inter alia</i>, an exciting new picture and outlook in mass spectrometry from which key developments grew that were at the time unimaginable, and continue to surprise us in its simplistic preeminence. We, and others, have demonstrated exceptional analytical utility. Our current research is focused on how best to understand, improve, and use these novel ionization processes through dedicated platforms and source developments. These ionization processes convert volatile and nonvolatile compounds from solid or liquid matrixes into gas-phase ions for analysis by mass spectrometry using, <i>e.g.</i>, mass-selected fragmentation and ion mobility spectrometry to provide accurate, and sometimes improved, mass and drift time resolution. The combination of research and discoveries demonstrated multiple advantages of the new ionization processes and established the basis of the successes that lead to the Biemann Medal and this Perspective. How the new ionization processes relate to traditional ionization is also presented, as well as how these technologies can be utilized in tandem through instrument modification and implementation to increase coverage of complex materials through complementary strengths.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142379826","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}
Stacey L Felgate, Elizabeth Jakobsson, Andrea Balderrama Subieta, Lars J Tranvik, Jeffrey A Hawkes
{"title":"Combined Quantification and Characterization of Dissolved Organic Matter by Liquid Chromatography-Mass Spectrometry Using Charged Aerosol Detection.","authors":"Stacey L Felgate, Elizabeth Jakobsson, Andrea Balderrama Subieta, Lars J Tranvik, Jeffrey A Hawkes","doi":"10.1021/jasms.4c00255","DOIUrl":"https://doi.org/10.1021/jasms.4c00255","url":null,"abstract":"<p><p>Dissolved organic matter (DOM) is a complex mixture of thousands of molecular formulas comprised of an unknown number of chemical compounds, the concentration and composition of which are critical to ecosystem function and biogeochemical cycling. Despite its importance, our understanding of the DOM composition is lacking. This is principally due to its molecular complexity, which means that no single method is capable of describing DOM in its entirety. Quantification is typically done by proxy (e.g., relative to carbon content) and does not necessarily match well to compositional data, due to incomplete analytical windows and selectivity of different analytical methods. We present an integrated liquid chromatography (LC)-diode array detector (DAD)-charged aerosol detector (CAD)-mass spectrometry (MS) pipeline designed to both characterize and quantify solid-phase extractable DOM (SPE-DOM) in a single analysis. We applied this method to a set of eight Swedish water bodies sampled in the summer and winter. Chromophoric SPE-DOM was proportionally higher in samples with higher SPE-DOM concentrations but remained relatively consistent between sampling occasions. Ionizable SPE-DOM was relatively consistent across sites but was proportionally higher in summer. Overall, the carbon content of DOM was very consistently ∼40% across sites in both summer and winter. These findings suggest that SPE-DOM concentration at these sites is driven by (presumably allochthonous) chromophoric inputs, with an increased relative contribution in summer of material that is more ionizable and less chromophoric and may be either autochthonous or selectively enriched from allochthonous sources. Thus, with minimal additional effort, this method provided further compositional insights not attained by any single analysis in isolation.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142378926","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}
Nico Fransaert, Allyson Robert, Bart Cleuren, Jean V Manca, Dirk Valkenborg
{"title":"Identifying Process Differences with ToF-SIMS: An MVA Decomposition Strategy.","authors":"Nico Fransaert, Allyson Robert, Bart Cleuren, Jean V Manca, Dirk Valkenborg","doi":"10.1021/jasms.4c00327","DOIUrl":"10.1021/jasms.4c00327","url":null,"abstract":"<p><p>In time-of-flight secondary ion mass spectrometry (ToF-SIMS), multivariate analysis (MVA) methods such as principal component analysis (PCA) are routinely employed to differentiate spectra. However, additional insights can often be gained by comparing processes, where each process is characterized by its own start and end spectra, such as when identical samples undergo slightly different treatments or when slightly different samples receive the same treatment. This study proposes a strategy to compare such processes by decomposing the loading vectors associated with them, which highlights differences in the relative behavior of the peaks. This strategy identifies key information beyond what is captured by the loading vectors or the end spectra alone. While PCA is widely used, partial least-squares discriminant analysis (PLS-DA) serves as a supervised alternative and is the preferred method for deriving process-related loading vectors when classes are narrowly separated. The effectiveness of the decomposition strategy is demonstrated using artificial spectra and applied to a ToF-SIMS materials science case study on the photodegradation of N719 dye, a common dye in photovoltaics, on a mesoporous TiO<sub>2</sub> anode. The study revealed that the photodegradation process varies over time, and the resulting fragments have been identified accordingly. The proposed methodology, applicable to both labeled (supervised) and unlabeled (unsupervised) spectral data, can be seamlessly integrated into most modern mass spectrometry data analysis workflows to automatically generate a list of peaks whose relative behavior varies between two processes, and is particularly effective in identifying subtle differences between highly similar physicochemical processes.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142374951","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}
Margaret Hoare, Ruiyue Tan, Isabella Militi, Kevin A Welle, Kyle Swovick, Jennifer R Hryhorenko, Sina Ghaemmaghami
{"title":"Enzymatic Synthesis of Isotopically Labeled Hydrogen Peroxide for Mass Spectrometry-Based Applications.","authors":"Margaret Hoare, Ruiyue Tan, Isabella Militi, Kevin A Welle, Kyle Swovick, Jennifer R Hryhorenko, Sina Ghaemmaghami","doi":"10.1021/jasms.4c00326","DOIUrl":"https://doi.org/10.1021/jasms.4c00326","url":null,"abstract":"<p><p>Methionine oxidation is involved in multiple biological processes including protein misfolding and enzyme regulation. However, it is often challenging to measure levels of methionine oxidation by mass spectrometry, in part due to the prevalence of artifactual oxidation that occurs during the sample preparation and ionization steps of typical proteomic workflows. Isotopically labeled hydrogen peroxide (H<sub>2</sub><sup>18</sup>O<sub>2</sub>) can be used to block unoxidized methionines and enables accurate measurement of <i>in vivo</i> levels of methionine oxidation. However, H<sub>2</sub><sup>18</sup>O<sub>2</sub> is an expensive reagent that can be difficult to obtain from commercial sources. Here, we report a method for synthesizing H<sub>2</sub><sup>18</sup>O<sub>2</sub> in-house. Glucose oxidase catalyzes the oxidation of β-d-glucose and produces hydrogen peroxide in the process. We took advantage of this reaction to enzymatically synthesize H<sub>2</sub><sup>18</sup>O<sub>2</sub> from <sup>18</sup>O<sub>2</sub> and assessed its concentration, purity, and utility in measuring methionine oxidation levels by mass spectrometry.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142370692","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":"Faces of Mass Spectrometry/Mike Morris.","authors":"Anne Brenner, J D Brookbank","doi":"10.1021/jasms.4c00386","DOIUrl":"https://doi.org/10.1021/jasms.4c00386","url":null,"abstract":"","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142370693","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}
Romain Magny, Bertrand Lefrère, Emmanuel Roulland, Nicolas Auzeil, Soha Farah, Camille Richeval, Alexandr Gish, Dominique Vodovar, Laurence Labat, Pascal Houzé
{"title":"Feature-Based Molecular Network for New Psychoactive Substance Identification: The Case of Synthetic Cannabinoids in a Seized e-Liquid and Biological Samples.","authors":"Romain Magny, Bertrand Lefrère, Emmanuel Roulland, Nicolas Auzeil, Soha Farah, Camille Richeval, Alexandr Gish, Dominique Vodovar, Laurence Labat, Pascal Houzé","doi":"10.1021/jasms.4c00009","DOIUrl":"10.1021/jasms.4c00009","url":null,"abstract":"<p><p>The comprehensive detection of new psychoactive substances, including synthetic cannabinoids along with their associated metabolites in biological samples, remains an analytical challenge. To detect these chemicals, untargeted approaches using appropriate bioinformatic tools such as molecular networks are useful, albeit it necessitates as a prerequisite the identification of a node of interest within the cluster. To illustrate it, we reported in this study the identification of synthetic cannabinoids and some of their metabolites in seized e-liquid, urine, and hair collected from an 18-year-old poisoned patient hospitalized for neuropsychiatric disorders. A comprehensive analysis of the seized e-liquid was performed using gas chromatography coupled with electron ionization mass spectrometry, <sup>1</sup>H NMR, and liquid chromatography coupled with high resolution tandem mass spectrometry combined with data processing based on molecular network strategy. It allowed researchers to detect in the e-liquid known synthetic cannabinoids including MDMB-4en-PINACA, EDMB-4en-PINACA, MMB-4en-PINACA, and MDMB-5F-PICA. Compounds corresponding to transesterification of MDMB-4en-PINACA with pentenol, glycerol, and propylene glycol were also identified. Regarding the urine sample of the patient, metabolites of MDMB-4en-PINACA were detected, including MDMB-4en-PINACA butanoic acid, dihydroxylated MDMB-4en-PINACA butanoic acid, and glucurono-conjugated MDMB-4en-PINACA butanoic acid. Hair analysis of the patient allowed the detection of MDMB-4en-PINACA and MDMB-5F-PICA in the two investigated hair segments. This untargeted analysis of seized materials and biological samples demonstrates the utility of the molecular network strategy in identifying closely related compounds and metabolites of synthetic cannabinoids. It also emphasizes the need for developing strategies to anchor molecular networks, especially for new psychoactive substances.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142071707","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}
Rory P Downham, Christopher H Vane, Benedict Gannon, Lydia A Olaka, Mark P Barrow
{"title":"Sewage and Organic Pollution Compounds in Nairobi River Urban Sediments Characterized by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS).","authors":"Rory P Downham, Christopher H Vane, Benedict Gannon, Lydia A Olaka, Mark P Barrow","doi":"10.1021/jasms.4c00229","DOIUrl":"10.1021/jasms.4c00229","url":null,"abstract":"<p><p>Nairobi River sediments from locations adjacent to the Kawangware and Kiambio slums were analyzed via Fourier transform ion cyclotron resonance mass spectrometry with atmospheric pressure photoionization (APPI-FT-ICR-MS). The data from these ultrahigh resolution, untargeted measurements provided new insights into the impacts of local anthropogenic activity, which included likely benzo- and dibenzothiophene pollution with a suspected petrogenic origin, and prominent surfactant-like compositions. Other features in the data included highly abundant tetra-oxygenated compounds, and oxygenated nitrogen compounds with sphingolipid interpretations. Most notably, several hydrocarbon and oxygenated compound classes in the sediment data featured intensity patterns consistent with steroid molecular formulas, including those associated with sewage contamination investigatory work. In support of this interpretation, standards of cholesterol, β-sitosterol, stigmasterol, coprostanol, cholestanol, and 5α-sitostanol were analyzed via APPI, to explore steroid ionization behavior. Generally, these analytes produced radical molecular ions ([M]<sup>•+</sup>), and water-loss pseudo molecular ion species ([M-H<sub>2</sub>O]<sup>•+</sup> and [M+H-H<sub>2</sub>O]<sup>+</sup>), among various other less intense contributions. The absence of pseudo molecular protonated species ([M+H]<sup>+</sup>) was notable for these compounds, because these are often assumed to form with APPI. The standard measurements demonstrated how steroids can create the observed intensity patterns in FT-ICR-MS data, and hence these patterns have the potential to indicate sewage contamination in the analysis of other complex environmental samples. The steroid interpretation for the Kawangware and Kiambio data was further verified by subjecting the steroid standard radical molecular ions to collision-induced dissociation and comparing the detected fragments to those for the corresponding isolated ions from a Kawangware sediment sample.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11450967/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142124389","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":"MSIGen: An Open-Source Python Package for Processing and Visualizing Mass Spectrometry Imaging Data.","authors":"Emerson Hernly, Hang Hu, Julia Laskin","doi":"10.1021/jasms.4c00178","DOIUrl":"10.1021/jasms.4c00178","url":null,"abstract":"<p><p>Mass spectrometry imaging (MSI) provides information about the spatial localization of molecules in complex samples with high sensitivity and molecular selectivity. Although point-wise data acquisition, in which mass spectra are acquired at predefined points in a grid pattern, is common in MSI, several MSI techniques use line-wise data acquisition. In line-wise mode, the imaged surface is continuously sampled along consecutive parallel lines and MSI data are acquired as a collection of line scans across the sample. Furthermore, aside from the standard imaging mode in which full mass spectra are acquired, other acquisition modes have been developed to enhance molecular specificity, enable separation of isobaric and isomeric species, and improve sensitivity to facilitate the imaging of low abundance species. These methods, including MS/MS-MSI in both MS<sup>2</sup> and MS<sup>3</sup> modes, multiple-reaction monitoring (MRM)-MSI, and ion mobility spectrometry (IMS)-MSI have all demonstrated their capabilities, but their broader implementation is limited by the existing MSI analysis software. Here, we present MSIGen, an open-source Python package for the visualization of MSI experiments performed in line-wise acquisition mode containing MS<sup>1</sup>, MS<sup>2</sup>, MRM, and IMS data, which is available at https://github.com/LabLaskin/MSIGen. The package supports multiple vendor-specific and open-source data formats and contains tools for targeted extraction of ion images, normalization, and exportation as images, arrays, or publication-style images. MSIGen offers multiple interfaces, allowing for accessibility and easy integration with other workflows. Considering its support for a wide variety of MSI imaging modes and vendor formats, MSIGen is a valuable tool for the visualization and analysis of MSI data.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142103240","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":"Nanoelectrode Atmospheric Pressure Chemical Ionization Mass Spectrometry.","authors":"Nicole C Auvil, Mark E Bier","doi":"10.1021/jasms.4c00117","DOIUrl":"10.1021/jasms.4c00117","url":null,"abstract":"<p><p>A small ionization needle with an ultrasharp, ultrafine tip is introduced. It is lab-fabricated from tungsten wire and serves as a corona discharge emitter in nanoelectrode atmospheric pressure chemical ionization mass spectrometry (nAPCI-MS). Tip radii ranged from 8 to 44 nm, up to 44× smaller than the sharpest previously reported corona needle. Because of this, nAPCI was able to operate at +1.0 kV with no auxiliary counter electrode. Alternatively, at +1.2 kV, nAPCI could be enclosed in a small plastic assembly for headspace analysis with a sampling tube attachment as long as 15 m. No added heat or gas flow was necessary. The efficacy of nAPCI-MS was demonstrated through needle durability studies and direct analysis of vapors from real-world samples. Provisional identifications include ibuprofen from a pharmaceutical tablet, albuterol aerosol sprayed from a medical inhaler, cocaine from paper currency, caffeine from a fingertip, and bisphenol E from a paper receipt.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11450814/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141449283","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}