International Journal of Mass Spectrometry最新文献

{"title":"Richard A. J. O'Hair – A mass spectrometrist who is showing that gas-phase ion chemistry is not just a science but an art","authors":"Gavin E. Reid PhD., Victor Ryzhov Ph.D.","doi":"10.1016/j.ijms.2024.117367","DOIUrl":"10.1016/j.ijms.2024.117367","url":null,"abstract":"","PeriodicalId":338,"journal":{"name":"International Journal of Mass Spectrometry","volume":"507 ","pages":"Article 117367"},"PeriodicalIF":1.6,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142703826","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":"Can OPAH ions be a source of CO and HCO in the interstellar medium? Lessons learned from the unimolecular dissociation of dibenzofuran and dibenz[b,f]oxepin radical cations","authors":"Nicholas Zinck ,&nbsp;Andras Bodi ,&nbsp;Paul M. Mayer","doi":"10.1016/j.ijms.2024.117366","DOIUrl":"10.1016/j.ijms.2024.117366","url":null,"abstract":"<div><div>Unlike polycyclic aromatic hydrocarbons (PAHs), which are recognized to be key players in interstellar and astrochemistry, less is known about the astrochemical relevance of oxygen-containing PAHs (OPAHs). Small O-containing molecules such as CO and HCO are ubiquitous in the interstellar medium and understanding how OPAHs may be a source for these critical small molecules is important. To this end, we have studied the unimolecular reactions of two ionized OPAHs, dibenzofuran (<strong>1</strong>^{<strong>+•</strong>}) and dibenz[b,f]oxepin (<strong>2</strong>^{<strong>+•</strong>}) with tandem mass spectrometry (collision-energy resolved dissociation) and imaging photoelectron photoion coincidence spectroscopy (iPEPICO). Collision-induced dissociation (CID) results show the competition between the loss of carbon monoxide (CO) and loss of 29 Da (either the formyl radical (HCO) or sequential H loss), with the latter being the dominant reaction. Rice–Ramsperger–Kassel–Marcus (RRKM) modeling of the iPEPICO data, on the other hand, is consistent with the loss of CO from the parent ion at the dissociative ionization onset, and, in the case of <strong>2</strong>^{<strong>+•</strong>}, sequential H-atom loss from this product. There is significant difference between the two structurally similar systems. In <strong>1</strong>^{<strong>+•</strong>}, dissociation requires around 4 eV of ion internal energy, while only 2.5 eV internal energy is required for <strong>2</strong>^{<strong>+•</strong>} to fragment. Calculations at the CAM-B3LYP/6–311++G(d,p) level of theory were used to examine the reaction pathways. For CO loss in <strong>1</strong>^{<strong>+•</strong>}, the reaction is initiated by a ring expansion followed by contraction of the central ring forming an ion–molecule complex between protonated cyclopenta[3,4]cyclobuta[1,2]benzene and CO. HCO loss is preceded by H migration to a bridging carbon vicinal to the oxygen atom and subsequent ring re-organization to form a low energy cyclopenta[c][1]benzopyran cation. This channel is higher enough in energy to preclude its participation near threshold, but not at higher internal energies reached in the CID experiment, which could therefore involve both sequential H loss and HCO loss. In <strong>2</strong>^{<strong>+•</strong>}, the reaction starts with an opening of the central O-containing ring, lowering the energy demand relative to <strong>1</strong>^{<strong>+•</strong>}.</div></div>","PeriodicalId":338,"journal":{"name":"International Journal of Mass Spectrometry","volume":"507 ","pages":"Article 117366"},"PeriodicalIF":1.6,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652243","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":"Complexation of diserinol isophthalamide with phosphorylated biomolecules in electrospray ionization mass spectrometry","authors":"Madeline Schultz,&nbsp;Neil A. Ellis,&nbsp;Nwanne D. Banor,&nbsp;Daniel A. Thomas","doi":"10.1016/j.ijms.2024.117364","DOIUrl":"10.1016/j.ijms.2024.117364","url":null,"abstract":"<div><div>Electrospray ionization (ESI) enables gentle transfer of biomolecules from solution to vacuum, facilitating the study of biomolecular structure under highly controlled conditions. However, biomolecules are desolvated during the ESI process, and the loss of ionic hydrogen bonds to solvent molecules can drive structural rearrangement, most prominently at solvent-exposed charge sites. Microsolvation reagents can bind to these bare charge sites in ESI mass spectrometry (ESI–MS) experiments, providing alternative intermolecular interaction partners. Previously, 18-crown-6 was shown to be an effective reagent for binding to cationic monoalkylammonium residues. More recently, diserinol isophthalamide (DIP) was reported as an analogous anionic microsolvation reagent, primarily for carboxylate residues of small model peptides. Herein, we expand upon this work to examine the complexation of DIP, 1,1’-(1,2-phenylene)bis(3-phenylurea) (PBP), and triclocarban (TCC) with molecules featuring a terminal or linking phosphate moiety. Specifically, using ESI–MS, we assess the binding of these reagents with dimethyl phosphate (DMP), cyclic adenosine monophosphate (cAMP), dibutyryl cAMP, RNA dinucleotides ApU and CpG, and angiotensin II phosphate (DRVpYIHPF). For DMP, the smallest target molecule, reagents TCC, PBP and DIP showed favorable adduction. However, for larger systems, PBP and TCC showed reduced complexation, which was attributed to steric hindrance from the terminal aromatic moieties of PBP and the limited hydrogen bonding network of TCC. Overall, of the three reagents, DIP showed the most consistent performance for anionic microsolvation of phosphate groups, facilitating future studies of gas-phase biomolecular structure and the effects of microsolvation.</div></div>","PeriodicalId":338,"journal":{"name":"International Journal of Mass Spectrometry","volume":"507 ","pages":"Article 117364"},"PeriodicalIF":1.6,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652334","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":"Unravelling the favorability of radical-directed xn-H2O dissociation at serine and threonine","authors":"Evan E. Hubbard,&nbsp;Ryan R. Julian","doi":"10.1016/j.ijms.2024.117363","DOIUrl":"10.1016/j.ijms.2024.117363","url":null,"abstract":"<div><div>Among tandem-mass-spectrometry approaches, radical-directed dissociation (RDD) is uniquely sensitive to molecular structure because the location and types of cleavage observed are dictated by radical migration propensities. Although the underlying chemistry for many RDD fragmentation pathways has been previously explained, x_n-H₂O fragment ions that occur exclusively at serine and threonine residues, have not been examined in detail. Creation of this fragment type inherently requires two dissociation events, one to lose water and another to cleave the peptide backbone. Double dissociations are typically disfavored relative to pathways requiring a single cleavage, yet x_n-H₂O fragment ions are abundant in RDD spectra. To understand why this fragmentation pathway is favorable, we used a combination of computational chemistry and experiments on peptides with a variety of covalent modifications. Our results explore the energetics, location, and migration of the radical in each step of the mechanism, revealing that favorability can be attributed to the stability of the required radical intermediates and access to low-energy pathways connecting them. Ultimately, the abundant nature of x_n-H₂O ions and the selectivity associated with their exclusive generation at Ser/Thr provides high value sequence information in RDD experiments.</div></div>","PeriodicalId":338,"journal":{"name":"International Journal of Mass Spectrometry","volume":"507 ","pages":"Article 117363"},"PeriodicalIF":1.6,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142586170","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":"Gas phase proton affinities of proline-containing peptides. 1: ProGly, ProAla, ProVal, ProLeu, ProIle, and ProPro","authors":"Henry Cardwell ,&nbsp;Paul Acoria ,&nbsp;Alexis Brender A Brandis ,&nbsp;Kathy Huynh ,&nbsp;Madeleine Lamb ,&nbsp;Sophie Messinger ,&nbsp;Daria Moody ,&nbsp;Laurel Nicks ,&nbsp;Hao Qian ,&nbsp;Marcus Quint ,&nbsp;Trinh Ton ,&nbsp;Anna Grace Towler ,&nbsp;Michael Valasquez ,&nbsp;Jennifer Poutsma ,&nbsp;John C. Poutsma","doi":"10.1016/j.ijms.2024.117352","DOIUrl":"10.1016/j.ijms.2024.117352","url":null,"abstract":"<div><div>The gas-phase proton affinities (PA) for a series of proline-containing dipeptides have been measured in an ESI triple quadrupole instrument using the extended kinetic method. Proton affinities for ProGly (<strong>1</strong>), ProAla (<strong>2</strong>), ProVal (<strong>3</strong>), ProLeu (<strong>4</strong>), ProIle (<strong>5</strong>), and ProPro (<strong>6</strong>) were determined to be 969.6 ± 7.8, 990.4 ± 7.7, 987.6 ± 7.9, 982.8 ± 8.0, 988.8 ± 10.1, and 996.5 ± 12.2 kJ/mol, respectively. Predictions for the proton affinities for <strong>1</strong>–<strong>6</strong> were also obtained through isodesmic calculations at the B3LYP/6-311++G(d,p)//B3LYP/6-31+G(d) level of theory. The predicted proton affinities for <strong>1</strong> and <strong>6</strong> of 966.9 and 991.0 kJ/mol are in agreement with the experimental values. However, the predicted proton affinities for <strong>2</strong>–<strong>5</strong> of 973.5, 975.9, 975.7, and 975.9 are between 8 and 15 kJ/mol lower than the experimental values. Additional calculations with a larger basis set (B3LYP/6-311++G(2df,2p), inclusion of dispersion (B3LYP-D3/6-311++G(d,p)), switching to second order perturbation theory (MP2/6-31++G(d,p) and MP2/6-311++G(2df,2p), or switching density functional (M06-2x/6-311++G(d,p) and M06-2x/6-311++G(2df,2p) show only modest changes in derived thermochemistry lending support to the original calculations. We recommend using the experimental proton affinities for ProGly and ProPro and using the calculated values for ProAla, ProVal, ProLeu, and ProIle with the experimental proton affinities as upper limits.</div></div>","PeriodicalId":338,"journal":{"name":"International Journal of Mass Spectrometry","volume":"507 ","pages":"Article 117352"},"PeriodicalIF":1.6,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552386","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":"Monovalent nickel ion as ionization probe in matrix-assisted laser desorption/ionization mass spectrometry","authors":"Toshiki Horikoshi ,&nbsp;Jiawei Xu ,&nbsp;Mengrui Yang ,&nbsp;Wei Chang ,&nbsp;Tatsuya Fujino","doi":"10.1016/j.ijms.2024.117354","DOIUrl":"10.1016/j.ijms.2024.117354","url":null,"abstract":"<div><div>We have developed NiO/HM20, a matrix composed of NiO nanoparticles (NiO) loaded on zeolite surface, for matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS). By photoexcitation, monovalent nickel ion (Ni⁺) was dominantly observed with high intensity. The mechanism of Ni⁺ production was studied by picosecond time-resolved emission spectroscopy. By loading NiO on the zeolite surface, a new relaxation pathway to other electronic excited states was observed, which increased the lifetime of electron–hole pairs and promoted the reduction of nickel. The long-lived charge-separated electronic excited state corresponding to the large polarization of NiO was confirmed by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction spectroscopy (XRD). The correlation between the Auger parameter related to the polarization energy and the Ni⁺ peak intensity in the mass spectrum was confirmed. By applying the developed NiO/HM20 matrix to the MS measurement of small molecules, we found that molecules were ionized through complex formation with Ni⁺ using the coordination of lone electron pairs or π-electrons in the analyte molecules.</div></div>","PeriodicalId":338,"journal":{"name":"International Journal of Mass Spectrometry","volume":"506 ","pages":"Article 117354"},"PeriodicalIF":1.6,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529483","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":"A simplified coaxial ion trap mass analyzer: Characterization of the simplified toroidal ion trap with a rectilinear ion guide","authors":"David V. Sirbescu-Stanley ,&nbsp;Kristina M. Lemmer ,&nbsp;Daniel E. Austin ,&nbsp;Nicholas R. Taylor","doi":"10.1016/j.ijms.2024.117353","DOIUrl":"10.1016/j.ijms.2024.117353","url":null,"abstract":"<div><div>A new miniature coaxial ion trap mass analyzer with a rectilinear ion guide has been constructed using a combination of planar and cylindrical electrodes. The results reported here focus on characterizing the performance of the rectilinear ion guide and simplified toroidal ion trap components. The simplified toroidal ion trap was found to have an ion capacity in excess of 10⁵ ions and mass spectral resolution of 0.5–0.6 when used as a mass analyzer. The ion storage efficiency within the toroidal trapping region was evaluated and found the stored ion population decreased exponentially with storage time. Ion losses depended slightly on the stored β_z condition. Ion losses within the toroidal region are attributed primarily to field instabilities at the intersection point of the two components while charge exchange reactions were observed but considered a minor loss mechanism. The ability to mass selectively ejection ions of a specific mass from the toroidal trapping region was characterized and found to approach 100 % efficiency under appropriate ejection conditions.</div></div>","PeriodicalId":338,"journal":{"name":"International Journal of Mass Spectrometry","volume":"506 ","pages":"Article 117353"},"PeriodicalIF":1.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529484","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":"The amenability of different solvents to electrospray ionization mass spectrometry","authors":"Charles Killeen,&nbsp;Antonia Kropp,&nbsp;Ian C. Chagunda,&nbsp;Emily C. Jackson,&nbsp;J. Scott McIndoe","doi":"10.1016/j.ijms.2024.117349","DOIUrl":"10.1016/j.ijms.2024.117349","url":null,"abstract":"<div><div>Electrospray ionization mass spectrometry is capable of transferring ions from solution to the gas phase across a broad range of solvents. A systematic investigation of the relative performance of different solvents has not been previously conducted, and we sought to remedy this situation. Fourteen solvents across a wide range of polarities were investigated for their ability to provide strong signals for four permanently charged ions. We found the best solvents to be acetone, acetonitrile, dichloromethane, tetrahydrofuran, and the previously unused (in an ESI-MS context) trifluorotoluene.</div></div>","PeriodicalId":338,"journal":{"name":"International Journal of Mass Spectrometry","volume":"506 ","pages":"Article 117349"},"PeriodicalIF":1.6,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142446270","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":"Characterization of glycylglycyltyrosine radical cations: Insights into β-radical formation and N–Cα peptide bond dissociation at the tyrosine residue","authors":"Yinan Li ,&nbsp;Jonathan Martens ,&nbsp;Wai Kit Tang ,&nbsp;Giel Berden ,&nbsp;Jos Oomens ,&nbsp;Ivan K. Chu","doi":"10.1016/j.ijms.2024.117351","DOIUrl":"10.1016/j.ijms.2024.117351","url":null,"abstract":"<div><div>We investigated the dissociation and characterization of radical cations of glycylglycyltyrosine [GGY]^•+, focusing on β-radical-induced N–C_α peptide bond cleavage reactions at the tyrosyl residue. By combining density functional theory (DFT) calculations with experimental studies utilizing low-energy collision-induced dissociation (CID) mass spectrometry and deuterium labeling on the two β-hydrogen atoms of the tyrosyl residue in [GGY]^•+, we elucidated the intricacies of the β-radical structure and its origin. Unlike tryptophan-containing [GGW]^•+, which forms canonical π-radical precursors, infrared multiphoton dissociation (IRMPD) spectroscopy results reveal that the β-radical [GGY_β^•]⁺ isomerizes from the phenoxy-radical [GGY_o^•]⁺, with the radical localized on the β-carbon of the tyrosyl residue and the phenolic oxygen atom, respectively. The isomerization barriers from [GGY_o^•]⁺ to [GGY_β^•]⁺ are &lt;109 kJ mol⁻¹.</div></div>","PeriodicalId":338,"journal":{"name":"International Journal of Mass Spectrometry","volume":"506 ","pages":"Article 117351"},"PeriodicalIF":1.6,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142442861","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":"Influence of 5-fluorination on the structure and glycosidic bond stability of the protonated canonical DNA and RNA cytidine nucleosides: Oh, what a difference the 2′-hydroxy substituent makes?","authors":"Zachary J. Devereaux ,&nbsp;E.O. Soley ,&nbsp;G. Berden ,&nbsp;J. Oomens ,&nbsp;M.T. Rodgers","doi":"10.1016/j.ijms.2024.117350","DOIUrl":"10.1016/j.ijms.2024.117350","url":null,"abstract":"<div><div>Fluorinated nucleosides are well-established as anticancer and antiviral medications. As with many pharmaceuticals, the effects of fluorine modifications are often only partially understood. In this work, the effects of 5-fluorination of the cytosine nucleobase on the structures and glycosidic bond stabilities of the protonated canonical DNA and RNA cytidine nucleosides (dCyd and Cyd) are examined. Infrared multiple photon dissociation action spectroscopy experiments and electronic structure calculations are employed to probe the structural influences of 5-fluorination. Spectral signatures in the IR fingerprint and hydrogen-stretching regions indicate that 5-fluorination heavily directs for and solely produces O2 protonation <em>para</em> to the 5-fluoro substituent. This differs from the canonical cytidine nucleosides where roughly equal populations of O2 and N3 protonated structures were observed. Energy-resolved collision-induced dissociation experiments combined with survival yield analyses are performed to probe the influence of 5-fluorination on glycosidic bond stability. Trends in the energy-dependence of the survival yield curves indicate that 5-fluorination weakens the glycosidic bond, and that the influence of 5-fluorination on glycosidic bond stability is much greater for dCyd than Cyd. Theory also finds that 5-fluorination weakens the glycosidic bond but predicts that the influence of 5-fluorination on N-glycosidic bond stability is roughly the same for dCyd and Cyd. Oh, what a difference the 2′-hydroxy substituent makes?</div></div>","PeriodicalId":338,"journal":{"name":"International Journal of Mass Spectrometry","volume":"506 ","pages":"Article 117350"},"PeriodicalIF":1.6,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142442862","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}