Journal of Mass Spectrometry最新文献

{"title":"Dissociation Chemistry of Protonated α-, β- and Other Amino Acids Using Multiple Stage Tandem Mass Spectrometry","authors":"Daiki Asakawa","doi":"10.1002/jms.5100","DOIUrl":"https://doi.org/10.1002/jms.5100","url":null,"abstract":"<div>\u0000 \u0000 <p>To discriminate amino acid isomers by multiple stage tandem mass spectrometry (MSⁿ), the fragmentation of protonated amino acids were investigated by MSⁿ with collision-induced dissociation (CID) and density functional theory calculations. The CID of protonated α-amino acids results in a loss of 46 Da, corresponding to H₂O and CO, and iminium ions appear as resultant fragments. The CID of protonated β-amino acids also produces iminium ions, but the corresponding loss is 60 Da instead of 46 Da. H₂O loss initiates the fragmentation of protonated β-amino acids, producing protonated β-lactams as an intermediate. Subsequently, protonated β-lactams are easily converted to iminium ions and CH₂CO. By contrast, H₂O loss from the protonated forms of γ- and ε-amino acids provides protonated lactams with 5- and 7-membered rings, respectively. Protonated lactams with more than 5-membered rings provide stable fragments and do not undergo further degradation during CID. In addition, protonated forms of γ- and ε-amino acids undergo NH₃ loss as a competitive fragmentation pathway of H₂O loss, producing protonated lactones. Because the fragmentation of protonated amino acid by CID depends on the position of amino and carboxyl groups, the tandem mass spectrometry with CID can discriminate α-, β-, and other amino acids.</p>\u0000 </div>","PeriodicalId":16178,"journal":{"name":"Journal of Mass Spectrometry","volume":"59 12","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142674090","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":"Phytochemical Profiling by HPLC-ESI-MS/MS and In Vitro Investigation of the Antidiabetic Activity of Cassia bakeriana Bark Extract and Fractions","authors":"Diego G. Prado,&nbsp;Allisson B. Justino,&nbsp;Tiara da C. Silva,&nbsp;Sérgio A. L. de Morais,&nbsp;Mário M. Martins,&nbsp;Paula de S. Santos,&nbsp;Luís C. S. Cunha,&nbsp;Raquel M. F. de Sousa,&nbsp;Francisco J. T. de Aquino,&nbsp;Foued S. Espindola,&nbsp;Alberto de Oliveira","doi":"10.1002/jms.5099","DOIUrl":"10.1002/jms.5099","url":null,"abstract":"<div>\u0000 \u0000 <p>Type 2 diabetes mellitus is a global health problem, placing patients at a higher risk of developing cardiovascular diseases and cancer. This study investigates the antidiabetic potential of <i>Cassia bakeriana</i> bark extracts and fractions. We evaluate their ability to inhibit α-amylase and α-glucosidase enzymes and advanced glycation end-products (AGEs). The antioxidant potential was also examined. Extracts were prepared through maceration with hexane (HE) and ethanol (EE), and the fractions were obtained via liquid–liquid extraction from EE. Anti-enzymatic, anti-glycation, antioxidant, and cytotoxic assays were conducted in 96-well plates using different concentrations of samples to determine the half-maximal inhibitory concentration (IC₅₀). Active samples were further analyzed using HPLC-(−)-ESI-MS/MS. The ethyl acetate fraction (EAF) demonstrated a high percentage of α-amylase inhibition (94.0%) with a promising IC₅₀ value of 1.05 μg mL⁻¹. Additionally, EAF displayed 61.5% inhibition of α-glucosidase, with an IC₅₀ value of 537 μg mL⁻¹. The EE, EAF, and <i>n</i>-butanol fraction (BF) exhibited strong anti-glycation capacities. Furthermore, the EE, EAF, BF, and dichloromethane fractions showed promising antioxidant activity using the DPPH and ORAC methodologies. Cytotoxic activity was also evaluated with Vero cells, revealing no adverse effects on cell viability (CC₅₀ &gt; 512.0 μg mL⁻¹). Active samples predominantly comprised proanthocyanidins, flavonoids, and anthraquinone, representing the main constituents of C. <i>bakeriana</i> bark. This study provides the first assessment of the antidiabetic potential of <i>C. bakeriana</i> bark and a comprehensive analysis of the chemical composition of its active extracts and fractions, offering hope for future treatments.</p>\u0000 </div>","PeriodicalId":16178,"journal":{"name":"Journal of Mass Spectrometry","volume":"59 12","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142621923","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":"Advancing Native Mass Spectrometry Toward Cellular Biology","authors":"Kazumi Saikusa","doi":"10.1002/jms.5095","DOIUrl":"10.1002/jms.5095","url":null,"abstract":"<div>\u0000 \u0000 <p>Protein structure, including various post-translational modifications and higher-order structures, regulates diverse biological functions. Native mass spectrometry (native MS) is a powerful analytical technique used to determine the masses of biomolecules, such as proteins and their complexes, while preserving their native folding in solution. This method provides structural information on the composition of monomers or complexes and the stoichiometry of subunits within each complex, significantly contributing to protein structural analysis. Native MS has evolved to incorporate top–down approaches, enabling the characterization of proteoforms and non-covalent interactions between metabolites or proteins and specific targets. This perspective highlights the advancements in native MS for intracellular proteins and protein complexes, and discusses future research directions toward cellular biology.</p>\u0000 </div>","PeriodicalId":16178,"journal":{"name":"Journal of Mass Spectrometry","volume":"59 11","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142502157","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":"Strategies for Top–Down Hydrogen Deuterium Exchange-Mass Spectrometry: A Mini Review and Perspective","authors":"Joel B. Langford,&nbsp;Elizabeth Ahmed,&nbsp;Mulin Fang,&nbsp;Kellye Cupp-Sutton,&nbsp;Kenneth Smith,&nbsp;Si Wu","doi":"10.1002/jms.5097","DOIUrl":"https://doi.org/10.1002/jms.5097","url":null,"abstract":"<div>\u0000 \u0000 <p>Hydrogen deuterium-exchange mass spectrometry (HDX-MS) is commonly used in the study of protein dynamics and protein interactions. By measuring the isotopic exchange of backbone amide hydrogens in solution, HDX-MS offers valuable structural insights into challenging biological systems. Traditional HDX-MS approaches utilize bottom–up (BU) proteomics, in which deuterated proteins are digested before MS analysis. BU-HDX enables the characterization of proteins with various sizes in simple protein mixtures or complex biological samples such as cell lysates. However, BU methods are inherently limited by the inability to resolve protein sub-populations arising from different protein conformations, such as those arising from post-translational modifications (PTMs). Alternatively, top–down (TD) HDX-MS detects the global deuterium uptake at the intact proteoform level, allowing direct probing of structural changes due to protein–protein interactions, PTMs, or conformational changes. Combining TD-HDX-MS with electron-based fragmentation techniques, such as electron capture dissociation (ECD) and electron transfer dissociation (ETD), has demonstrated the feasibility of studying intact protein interactions with amino acid-level resolution. Here, we present a brief overview of methodologies, limitations, and applications of TD-HDX-MS using direct infusion techniques and LC-based approaches. Furthermore, we conclude with a perspective on the future directions for TD-HDX-MS.</p>\u0000 </div>","PeriodicalId":16178,"journal":{"name":"Journal of Mass Spectrometry","volume":"59 11","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142435382","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":"B4C-Assisted Paper Spray Ionization Mass Spectrometry","authors":"Dimei Hu,&nbsp;Lulu Yu,&nbsp;Zijian Wei,&nbsp;Lingpeng Zhan,&nbsp;Peiqi Luo","doi":"10.1002/jms.5098","DOIUrl":"https://doi.org/10.1002/jms.5098","url":null,"abstract":"<div>\u0000 \u0000 <p>A novel inorganic nonmetallic material boron carbide (B₄C) was applied in paper spray ionization to analyze organic molecules in both negative and positive modes. The utilization of B₄C has led to a notable enhancement in signal responses for various molecules, including bisphenols and drugs, by approximately two to four times. The limit of detection (LOD) of bisphenol AF and nilotinib standard solutions can reach 1 and 0.5 μg/mL, respectively. Moreover, linear relationships for bisphenol AF was established within the concentration range of 1–100 μg/mL, exhibiting strong correlation coefficients. Recovery experiments for BPAF in water samples from the inlet and outlet of a sewage treatment plant, conducted without any pretreatment, achieved a maximum recovery rate of 98.8% and an RSD below 9.78%.</p>\u0000 </div>","PeriodicalId":16178,"journal":{"name":"Journal of Mass Spectrometry","volume":"59 11","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142435290","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":"Pharmacokinetic Analysis of Gatifloxacin and Dexamethasone in Rabbit Ocular Biofluid Using a Sensitive and Selective LC–MS/MS Method","authors":"Arpon Biswas,&nbsp;Abhijit Deb Choudhury,&nbsp;Anjali Mishra,&nbsp;Sarvesh Kumar Verma,&nbsp;Amol Chhatrapati Bisen,&nbsp;Sachin Nashik Sanap,&nbsp;Sristi Agrawal,&nbsp;Mukesh Kumar,&nbsp;Shivansh Kumar,&nbsp;Rabi Sankar Bhatta","doi":"10.1002/jms.5088","DOIUrl":"10.1002/jms.5088","url":null,"abstract":"<div>\u0000 \u0000 <p>Bacterial keratitis (BK) is an infection that causes inflammation of the cornea and, if severe, can result in blindness. Topical fluoroquinolones combined with corticosteroids have been shown to be useful in the treatment of BK. A rapid, selective, and sensitive bioanalytical method for simultaneous quantification of Gatifloxacin (GAT) and Dexamethasone (DEX) has been developed and validated using tandem mass spectrometry (LC–MS/MS). Optimal separation was accomplished in under 5 min using an Agilent Zorbax C18 column (100 mm × 4.6 mm, 3.5 μm). The mobile phase was composed of a blend of 0.2% formic acid in triple distilled water and methanol with a flow rate of 0.65 mL/min in isocratic mode. GAT and DEX were detected in positive electrospray ionization multiple reaction monitoring mode (MRM), and the retention time was found to be at 1.64 and 2.93 min, respectively. The linearity of GAT and DEX was found to be in the range of 1.56–400 ng mL⁻¹ with good precision and accuracy. The method was validated according to USFDA regulatory guidelines. The validated method was effectively utilized for preclinical pharmacokinetic analysis of GAT and DEX in rabbit tear fluid following the topical application of a commercial formulation.</p>\u0000 </div>","PeriodicalId":16178,"journal":{"name":"Journal of Mass Spectrometry","volume":"59 10","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142348318","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":"Where You Protonate Matters: Deciphering the Unimolecular Chemistry of Protonated Myrcene and Linalool","authors":"Edgar White Buenger,&nbsp;Paul M. Mayer","doi":"10.1002/jms.5096","DOIUrl":"10.1002/jms.5096","url":null,"abstract":"<p>The unimolecular reactions of protonated myrcene and linalool were investigated by collision-induced dissociation and density functional theory calculations. Experiments on a triple quadrupole mass spectrometer showed that protonated myrcene undergoes two major unimolecular reactions losing propene and isobutene, and two minor reactions of ethene and propane loss. In each case, the product ion consists of a substituted five-member ring. Protonation of myrcene was found to form four distinct protomers, three of which can be significantly populated in the ion source. The observed fragmentation reactions were calculated and found to depend on the starting protomer. Each pathway consisted of several hydrogen-migration and ring-forming/opening steps on the way to the observed products. Likewise, protonation of linalool also produces three distinct protomers, with the global minimum being formed by protonation of a central double bond. The major reaction is water loss to form protonated myrcene, but two minor channels were also observed resulting in loss of acetone and isobutene. The calculated minimum energy reaction pathways were found to be consistent with the relative abundances of the ions in the experimental breakdown diagrams.</p>","PeriodicalId":16178,"journal":{"name":"Journal of Mass Spectrometry","volume":"59 10","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jms.5096","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142365524","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":"EDTA-Assisted MPT-MS for Trace Analysis of Heavy Metals in Fireworks","authors":"Gaosheng Zhao,&nbsp;Yuliang Huang,&nbsp;Maolin Yang,&nbsp;Lifeng Liu,&nbsp;Bin Jia,&nbsp;Ping Cheng","doi":"10.1002/jms.5093","DOIUrl":"https://doi.org/10.1002/jms.5093","url":null,"abstract":"<div>\u0000 \u0000 <p>A novel method was developed for the rapid detection of heavy metals in firework solutions with high sensitivity and minimal pretreatment by enriching them with ethylenediaminetetraacetic acid (EDTA) reagent and analyzing them using microwave plasma torch mass spectrometry (MPT-MS). Quantitative results showed that the limits of detection and quantification for heavy metals (Pb, Ba, Sr, and Ag) ranged from 0.05 to 0.25 and 0.38 to 0.71 μg·L⁻¹, respectively. The linear dynamic ranges covered at least two orders of magnitude, with correlation coefficients exceeding 0.99. Fireworks from five regions in China were also analyzed quantitatively, detecting heavy metals including Pb, Ba, Sr, and Ag, with recovery rates ranging from 87.9% to 107.5%. Good separation between the firework samples from different regions was achieved by using element ratios and principal component analysis (PCA). These results from the preliminary study showed that the EDTA-assisted MPT-MS combined with PCA is a powerful tool for characterizing firework samples and tracing them back to their sources, which is valuable to effectively regulate and manage banned fireworks.</p>\u0000 </div>","PeriodicalId":16178,"journal":{"name":"Journal of Mass Spectrometry","volume":"59 10","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142324628","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":"Investigating Anion Effects on Metal Ion Binding Interactions With Amyloid β Peptide by Ion Mobility Mass Spectrometry","authors":"Jingwei Zhang,&nbsp;Ashley Phetsanthad,&nbsp;Lingjun Li","doi":"10.1002/jms.5090","DOIUrl":"https://doi.org/10.1002/jms.5090","url":null,"abstract":"<p>The study of metal ion's role in the biological processes of Alzheimer's disease has spurred investigations into the coordination chemistry of amyloid beta peptide and its fragments. Nano-electrospray ionization mass spectrometry (nESI-MS) has been utilized to examine the stabilization of bound anions on multiprotein complexes without bulk solvent. However, the effects of anions on metal ion binding interactions with amyloid beta peptide have not been explored. This study directly examined metal-peptide complexes using nESI-MS and investigated the effects of various anions on the binding ratio and stability of these complexes from ammonium salt solutions. The results indicate that different anions have distinct effects on the binding ratio and stability of various metal-peptide complexes. Of these, the bicarbonate ion exhibits the highest binding ratios for metal-peptide complexes, while binding ratios for these complexes in phosphate are comparatively low. Our results suggest that acetate, formate, bicarbonate, and phosphate have weak affinities and act as weak stabilizers of the metal-peptide complex structure in the gas phase. Intriguingly, chloride and sulfate act as stabilizers of the metal-peptide complex in the gas phase. The rank order determined from these data is substantially different from the Hofmeister salt series in solution. Although this outcome was anticipated due to the reduced influence of anions and water solvation, our findings correlate well with expected anion binding in solution and emphasize the importance of both hydration layer and anion-metal-peptide binding effects for Hofmeister-type stabilization in solution. This approach proved useful in examining the interactions between metal ions and amyloid beta peptide, which are relevant to Alzheimer's disease, using direct ESI-MS.</p>","PeriodicalId":16178,"journal":{"name":"Journal of Mass Spectrometry","volume":"59 10","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jms.5090","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142324568","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":"An Expedited Qualitative Profiling of Free Amino Acids in Plant Tissues Using Liquid Chromatography-Mass Spectrometry (LC–MS) in Conjunction With MS-DIAL","authors":"Anish Kaachra,&nbsp;Anish Tamang,&nbsp;Vipin Hallan","doi":"10.1002/jms.5094","DOIUrl":"https://doi.org/10.1002/jms.5094","url":null,"abstract":"<div>\u0000 \u0000 <p>The estimation of relative levels of amino acids is crucial for understanding various biological processes in plants, including photosynthesis, stress tolerance, and the uptake and translocation of nutrients. A wide range of liquid chromatography (LC; HPLC/UHPLC)-based methods is available for measuring the quantity of amino acids in plants. Additionally, the coupling of LC with mass spectrometry (MS) significantly enhanced the robustness of existing chromatographic methods used for amino acid quantification. However, accurate annotation and integration of mass peaks can be challenging for plant biologists with limited experience in analyzing MS data, especially in studies involving large datasets with multiple treatments and/or replicates. Further, there are instances when the experiment demands an overall view of the amino acids profile rather than focusing on absolute quantification. The present protocol provides a detailed LC–MS method for obtaining a qualitative amino acids profile using MS-DIAL, a versatile and user-friendly program for processing MS data. Free amino acids were extracted from the leaves of control and Tomato leaf curl Palampur virus (ToLCPalV)-infected <i>Nicotiana benthamiana</i> plants. Extracted amino acids were derivatized and separated using UHPLC-QTOF, with each amino acid subsequently identified by aligning mass data with a custom text library created in MS-DIAL. Further, MS-DIAL was employed for internal standard-based normalization to obtain a qualitative profile of 15 amino acids in control and virus-infected plants. The outlined method aims to simplify the processing of MS data to quickly assess any modulation in amino acid levels in plants with a higher degree of confidence.</p>\u0000 </div>","PeriodicalId":16178,"journal":{"name":"Journal of Mass Spectrometry","volume":"59 10","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142320880","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}