1
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Gloaguen E, Mons M, Schwing K, Gerhards M. Neutral Peptides in the Gas Phase: Conformation and Aggregation Issues. Chem Rev 2020; 120:12490-12562. [PMID: 33152238 DOI: 10.1021/acs.chemrev.0c00168] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Combined IR and UV laser spectroscopic techniques in molecular beams merged with theoretical approaches have proven to be an ideal tool to elucidate intrinsic structural properties on a molecular level. It offers the possibility to analyze structural changes, in a controlled molecular environment, when successively adding aggregation partners. By this, it further makes these techniques a valuable starting point for a bottom-up approach in understanding the forces shaping larger molecular systems. This bottom-up approach was successfully applied to neutral amino acids starting around the 1990s. Ever since, experimental and theoretical methods developed further, and investigations could be extended to larger peptide systems. Against this background, the review gives an introduction to secondary structures and experimental methods as well as a summary on theoretical approaches. Vibrational frequencies being characteristic probes of molecular structure and interactions are especially addressed. Archetypal biologically relevant secondary structures investigated by molecular beam spectroscopy are described, and the influences of specific peptide residues on conformational preferences as well as the competition between secondary structures are discussed. Important influences like microsolvation or aggregation behavior are presented. Beyond the linear α-peptides, the main results of structural analysis on cyclic systems as well as on β- and γ-peptides are summarized. Overall, this contribution addresses current aspects of molecular beam spectroscopy on peptides and related species and provides molecular level insights into manifold issues of chemical and biochemical relevance.
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Affiliation(s)
- Eric Gloaguen
- CEA, CNRS, Université Paris-Saclay, CEA Paris-Saclay, Bât 522, 91191 Gif-sur-Yvette, France
| | - Michel Mons
- CEA, CNRS, Université Paris-Saclay, CEA Paris-Saclay, Bât 522, 91191 Gif-sur-Yvette, France
| | - Kirsten Schwing
- TU Kaiserslautern & Research Center Optimas, Erwin-Schrödinger-Straße 52, D-67663 Kaiserslautern, Germany
| | - Markus Gerhards
- TU Kaiserslautern & Research Center Optimas, Erwin-Schrödinger-Straße 52, D-67663 Kaiserslautern, Germany
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2
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Shayeghi A, Rieser P, Richter G, Sezer U, Rodewald JH, Geyer P, Martinez TJ, Arndt M. Matter-wave interference of a native polypeptide. Nat Commun 2020; 11:1447. [PMID: 32193414 PMCID: PMC7081299 DOI: 10.1038/s41467-020-15280-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 02/26/2020] [Indexed: 11/12/2022] Open
Abstract
The de Broglie wave nature of matter is a paradigmatic example of quantum physics and it has been exploited in precision measurements of forces and fundamental constants. However, matter-wave interferometry has remained an outstanding challenge for natural polypeptides, building blocks of life, which are fragile and difficult to handle. Here, we demonstrate the wave nature of gramicidin, a natural antibiotic composed of 15 amino acids. Its center of mass is delocalized over more than 20 times the molecular size in our time-domain Talbot-Lau interferometer. We compare the observed interference fringes with a model that includes both a rigorous treatment of the peptide’s quantum wave nature as well as a quantum chemical assessment of its optical properties to distinguish our result from classical predictions. The realization of quantum optics with this prototypical biomolecule paves the way for quantum-assisted measurements on a large class of biologically relevant molecules. Matter-wave interferometry of complex molecules is challenging due to difficulties in preparing and detecting molecular beams. Here the authors demonstrate quantum behavior of a polypeptide using matter-wave interference in an all-optical time-domain Talbot-Lau interferometer.
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Affiliation(s)
- A Shayeghi
- Faculty of Physics, University of Vienna, VCQ, Boltzmanngasse 5, A-1090, Vienna, Austria
| | - P Rieser
- Faculty of Physics, University of Vienna, VCQ, Boltzmanngasse 5, A-1090, Vienna, Austria
| | - G Richter
- Faculty of Physics, University of Vienna, VCQ, Boltzmanngasse 5, A-1090, Vienna, Austria
| | - U Sezer
- Faculty of Physics, University of Vienna, VCQ, Boltzmanngasse 5, A-1090, Vienna, Austria
| | - J H Rodewald
- Centre for Cold Matter, Blackett Laboratory, Imperial College London, Prince Consort Road, London, SW7 2AZ, United Kingdom
| | - P Geyer
- Faculty of Physics, University of Vienna, VCQ, Boltzmanngasse 5, A-1090, Vienna, Austria
| | - T J Martinez
- Department of Chemistry and the PULSE Institute, Stanford University, Stanford, CA, 94305, USA.,SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA
| | - M Arndt
- Faculty of Physics, University of Vienna, VCQ, Boltzmanngasse 5, A-1090, Vienna, Austria.
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3
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Hanley L, Wickramasinghe R, Yung YP. Laser Desorption Combined with Laser Postionization for Mass Spectrometry. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2019; 12:225-245. [PMID: 30786215 DOI: 10.1146/annurev-anchem-061318-115447] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Lasers with pulse lengths from nanoseconds to femtoseconds and wavelengths from the mid-infrared to extreme ultraviolet (UV) have been used for desorption or ablation in mass spectrometry. Such laser sampling can often benefit from the addition of a second laser for postionization of neutrals. The advantages offered by laser postionization include the ability to forego matrix application, high lateral resolution, decoupling of ionization from desorption, improved analysis of electrically insulating samples, and potential for high sensitivity and depth profiling while minimizing differential detection. A description of postionization by vacuum UV radiation is followed by a consideration of multiphoton, short pulse, and other postionization strategies. The impacts of laser pulse length and wavelength are considered for laser desorption or laser ablation at low pressures. Atomic and molecular analysis via direct laser desorption/ionization using near-infrared ultrashort pulses is described. Finally, the postionization of clusters, the role of gaseous collisions, sampling at ambient pressure, atmospheric pressure photoionization, and the addition of UV postionization to MALDI are considered.
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Affiliation(s)
- Luke Hanley
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, USA;
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4
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Polat S, Sayan P. Impacts of UV Radiation on the Polymorphic Transformation of β Glycine to α Glycine. CRYSTAL RESEARCH AND TECHNOLOGY 2017. [DOI: 10.1002/crat.201700103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Sevgi Polat
- Chemical Engineering Department; Marmara University; Istanbul 34722 TURKEY
| | - Perviz Sayan
- Chemical Engineering Department; Marmara University; Istanbul 34722 TURKEY
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5
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Schwing K, Gerhards M. Investigations on isolated peptides by combined IR/UV spectroscopy in a molecular beam – structure, aggregation, solvation and molecular recognition. INT REV PHYS CHEM 2016. [DOI: 10.1080/0144235x.2016.1229331] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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6
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Pelster A, Körsgen M, Kurosawa T, Morita H, Arlinghaus HF. ToF-SIMS and Laser-SNMS Imaging of Heterogeneous Topographically Complex Polymer Systems. Anal Chem 2016; 88:9638-9646. [PMID: 27661389 DOI: 10.1021/acs.analchem.6b02415] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Heterogeneous polymer coatings, such as those used in organic electronics and medical devices, are of increasing industrial importance. In order to advance the development of these types of systems, analytical techniques are required which are able to determine the elemental and molecular spatial distributions, on a nanometer scale, with very high detection efficiency and sensitivity. The goal of this study was to investigate the suitability of laser postionization secondary neutral mass spectrometry (Laser-SNMS) with a 157 nm postionization laser beam to image structured polymer mixtures and compare the results with time-of-flight secondary ion mass spectrometry (ToF-SIMS) measurements using Bi3+ primary ions. The results showed that Laser-SNMS is better suited than ToF-SIMS for unambiguous detection and submicrometer imaging of the wide range of polymers investigated. The data also showed that Laser-SNMS has the advantage of being much more sensitive (in general higher by more than an order of magnitude and peaking at up to 3 orders of magnitude) than ToF-SIMS while also showing superior performance on topographically complex structured insulating surfaces, due to significantly reduced field effects and a higher dynamic range as compared to ToF-SIMS. It is concluded that Laser-SNMS is a powerful complementary technique to ToF-SIMS for the analysis of heterogeneous polymers and other complex structured organic mixtures, providing submicrometer resolution and high sensitivity.
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Affiliation(s)
- Andreas Pelster
- Physikalisches Institut, University of Münster , Wilhelm-Klemm-Str. 10, 48149 Münster, Germany
| | - Martin Körsgen
- Physikalisches Institut, University of Münster , Wilhelm-Klemm-Str. 10, 48149 Münster, Germany
| | - Takako Kurosawa
- Advanced Research Division, Panasonic Corporation , 3-1-1 Yagumo-naka-machi, Moriguchi City, Osaka 570-8501, Japan
| | - Hiromi Morita
- Advanced Research Division, Panasonic Corporation , 3-1-1 Yagumo-naka-machi, Moriguchi City, Osaka 570-8501, Japan
| | - Heinrich F Arlinghaus
- Physikalisches Institut, University of Münster , Wilhelm-Klemm-Str. 10, 48149 Münster, Germany
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7
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Sezer U, Wörner L, Horak J, Felix L, Tüxen J, Götz C, Vaziri A, Mayor M, Arndt M. Laser-induced acoustic desorption of natural and functionalized biochromophores. Anal Chem 2015; 87:5614-9. [PMID: 25946522 PMCID: PMC4455108 DOI: 10.1021/acs.analchem.5b00601] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Laser-induced acoustic desorption
(LIAD) has recently been established
as a tool for analytical chemistry. It is capable of launching intact,
neutral, or low charged molecules into a high vacuum environment.
This makes it ideally suited to mass spectrometry. LIAD can be used
with fragile biomolecules and very massive compounds alike. Here,
we apply LIAD time-of-flight mass spectrometry (TOF-MS) to the natural
biochromophores chlorophyll, hemin, bilirubin, and biliverdin and
to high mass fluoroalkyl-functionalized porphyrins. We characterize
the variation in the molecular fragmentation patterns as a function
of the desorption and the VUV postionization laser intensity. We find
that LIAD can produce molecular beams an order of magnitude slower
than matrix-assisted laser desorption (MALD), although this depends
on the substrate material. Using titanium foils we observe a most
probable velocity of 20 m/s for functionalized molecules with a mass m = 10 000 Da.
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Affiliation(s)
- Uğur Sezer
- †University of Vienna, Faculty of Physics, VCQ and QuNaBioS, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Lisa Wörner
- †University of Vienna, Faculty of Physics, VCQ and QuNaBioS, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Johannes Horak
- †University of Vienna, Faculty of Physics, VCQ and QuNaBioS, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Lukas Felix
- ‡University of Basel, Department of Chemistry, St. Johannsring 19, 4056 Basel, Switzerland
| | - Jens Tüxen
- ‡University of Basel, Department of Chemistry, St. Johannsring 19, 4056 Basel, Switzerland
| | - Christoph Götz
- §University of Vienna, Max F. Perutz Laboratories, Research Institute of Molecular Pathology, QuNaBioS, Doktor-Bohr-Gasse 7, 1030 Vienna, Austria
| | - Alipasha Vaziri
- §University of Vienna, Max F. Perutz Laboratories, Research Institute of Molecular Pathology, QuNaBioS, Doktor-Bohr-Gasse 7, 1030 Vienna, Austria
| | - Marcel Mayor
- ‡University of Basel, Department of Chemistry, St. Johannsring 19, 4056 Basel, Switzerland.,∥Karlsruhe Institute of Technology (KIT), Institute of Nanotechnology, P.O. Box 3640, 76021 Karlsruhe, Germany
| | - Markus Arndt
- †University of Vienna, Faculty of Physics, VCQ and QuNaBioS, Boltzmanngasse 5, 1090 Vienna, Austria
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8
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Sezer U, Schmid P, Felix L, Mayor M, Arndt M. Stability of high-mass molecular libraries: the role of the oligoporphyrin core. JOURNAL OF MASS SPECTROMETRY : JMS 2015; 50:235-239. [PMID: 25601698 PMCID: PMC4322477 DOI: 10.1002/jms.3526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 09/19/2014] [Accepted: 10/13/2014] [Indexed: 06/04/2023]
Abstract
Molecular beam techniques are a key to many experiments in physical chemistry and quantum optics. In particular, advanced matter-wave experiments with high-mass molecules profit from the availability of slow, neutral and mass-selected molecular beams that are sufficiently stable to remain intact during laser heating and photoionization mass spectrometry. We present experiments on the photostability with molecular libraries of tailored oligoporphyrins with masses up to 25,000 Da. We compare two fluoroalkylsulfanyl-functionalized libraries based on two different molecular cores that offer the same number of anchor points for functionalization but differ in their geometry and electronic properties. A pentaporphyrin core stabilizes a library of chemically well-defined molecules with more than 1600 atoms. They can be neutrally desorbed with velocities as low as 20 m/s and efficiently analyzed in photoionization mass spectrometry.
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Affiliation(s)
- Uĝur Sezer
- University of Vienna, Faculty of Physics, VCQ and QuNaBioSBoltzmanngasse 5, 1090, Vienna, Austria
| | - Philipp Schmid
- University of Vienna, Faculty of Physics, VCQ and QuNaBioSBoltzmanngasse 5, 1090, Vienna, Austria
| | - Lukas Felix
- Department of Chemistry, University of BaselSt. Johannsring 19, 4056, Basel, Switzerland
| | - Marcel Mayor
- Department of Chemistry, University of BaselSt. Johannsring 19, 4056, Basel, Switzerland
- Karlsruhe Institute of Technology (KIT), Institute of NanotechnologyP.O. Box 3640, 76021, Karlsruhe
| | - Markus Arndt
- University of Vienna, Faculty of Physics, VCQ and QuNaBioSBoltzmanngasse 5, 1090, Vienna, Austria
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9
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Dörre N, Rodewald J, Geyer P, von Issendorff B, Haslinger P, Arndt M. Photofragmentation beam splitters for matter-wave interferometry. PHYSICAL REVIEW LETTERS 2014; 113:233001. [PMID: 25526125 DOI: 10.1103/physrevlett.113.233001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Indexed: 06/04/2023]
Abstract
Extending the range of quantum interferometry to a wider class of composite nanoparticles requires new tools to diffract matter waves. Recently, pulsed photoionization light gratings have demonstrated their suitability for high mass matter-wave physics. Here, we extend quantum interference experiments to a new class of particles by introducing photofragmentation beam splitters into time-domain matter-wave interferometry. We present data that demonstrate this coherent beam splitting mechanism with clusters of hexafluorobenzene and we show single-photon depletion gratings based both on fragmentation and ionization for clusters of vanillin. We propose that photofragmentation gratings can act on a large set of van der Waals clusters and biomolecules which are thermally unstable and often resilient to single-photon ionization.
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Affiliation(s)
- Nadine Dörre
- University of Vienna, Faculty of Physics, VCQ & QuNaBioS, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Jonas Rodewald
- University of Vienna, Faculty of Physics, VCQ & QuNaBioS, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Philipp Geyer
- University of Vienna, Faculty of Physics, VCQ & QuNaBioS, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Bernd von Issendorff
- University of Freiburg, Faculty of Physics, Stefan-Meier-Strasse 21, D-79104 Freiburg, Germany
| | - Philipp Haslinger
- University of Vienna, Faculty of Physics, VCQ & QuNaBioS, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Markus Arndt
- University of Vienna, Faculty of Physics, VCQ & QuNaBioS, Boltzmanngasse 5, A-1090 Vienna, Austria
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10
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Juffmann T, Ulbricht H, Arndt M. Experimental methods of molecular matter-wave optics. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2013; 76:086402. [PMID: 23907707 DOI: 10.1088/0034-4885/76/8/086402] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We describe the state of the art in preparing, manipulating and detecting coherent molecular matter. We focus on experimental methods for handling the quantum motion of compound systems from diatomic molecules to clusters or biomolecules.Molecular quantum optics offers many challenges and innovative prospects: already the combination of two atoms into one molecule takes several well-established methods from atomic physics, such as for instance laser cooling, to their limits. The enormous internal complexity that arises when hundreds or thousands of atoms are bound in a single organic molecule, cluster or nanocrystal provides a richness that can only be tackled by combining methods from atomic physics, chemistry, cluster physics, nanotechnology and the life sciences.We review various molecular beam sources and their suitability for matter-wave experiments. We discuss numerous molecular detection schemes and give an overview over diffraction and interference experiments that have already been performed with molecules or clusters.Applications of de Broglie studies with composite systems range from fundamental tests of physics up to quantum-enhanced metrology in physical chemistry, biophysics and the surface sciences.Nanoparticle quantum optics is a growing field, which will intrigue researchers still for many years to come. This review can, therefore, only be a snapshot of a very dynamical process.
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11
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Schmid P, Stöhr F, Arndt M, Tüxen J, Mayor M. Single-photon ionization of organic molecules beyond 10 kDa. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2013; 24:602-8. [PMID: 23444050 PMCID: PMC3622019 DOI: 10.1007/s13361-012-0551-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 11/27/2012] [Accepted: 11/30/2012] [Indexed: 05/15/2023]
Abstract
The volatilization and soft ionization of complex neutral macromolecules at low energies has remained an outstanding challenge for several decades. Most volatilization techniques in mass spectrometry produce ions already in the source and most of them lead to particle velocities in excess of several hundred meters per second. For many macromolecules, post-ionization is inefficient since electronic or optical excitations can be followed by competing non-ionizing internal conversion, electron recapture, or fragmentation processes. Here, we explore the laser-assisted volatilization of neutral perfluoroalkyl-functionalized tetraphenylporphyrins as well as their single-photon ionization using vacuum ultraviolet (VUV) light at 157 nm. A systematic investigation of the ionization curves allows us to determine the molecular velocity distribution and ionization cross sections. We demonstrate the detection of single photon ionized intact organic molecules in excess of 10 kDa from a slow molecular beam.
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Affiliation(s)
- Philipp Schmid
- University of Vienna, Faculty of Physics, VCQ Vienna, Austria
| | - Frederik Stöhr
- University of Vienna, Faculty of Physics, VCQ Vienna, Austria
| | - Markus Arndt
- University of Vienna, Faculty of Physics, VCQ Vienna, Austria
| | - Jens Tüxen
- Department of Chemistry, University of Basel, Basel, Switzerland
| | - Marcel Mayor
- Department of Chemistry, University of Basel, Basel, Switzerland
- Karlsruhe Institute of Technology (KIT), Institute of Nanotechnology, Karlsruhe, Germany
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12
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Gasper GL, Takahashi LK, Zhou J, Ahmed M, Moore JF, Hanley L. Laser desorption postionization mass spectrometry of antibiotic-treated bacterial biofilms using tunable vacuum ultraviolet radiation. Anal Chem 2011; 82:7472-8. [PMID: 20712373 DOI: 10.1021/ac101667q] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Laser desorption postionization mass spectrometry (LDPI-MS) with 8.0-12.5 eV vacuum ultraviolet synchrotron radiation is used to single photon ionize antibiotics and extracellular neutrals that are laser desorbed both from neat and intact bacterial biofilms. Neat antibiotics are optimally detected using 10.5 eV LDPI-MS but can be ionized using 8.0 eV radiation, in agreement with prior work using 7.87 eV LDPI-MS. Tunable vacuum ultraviolet radiation also postionizes laser desorbed neutrals of antibiotics and extracellular material from within intact bacterial biofilms. Different extracellular material is observed by LDPI-MS in response to rifampicin or trimethoprim antibiotic treatment. Once again, 10.5 eV LDPI-MS displays the optimum trade-off between improved sensitivity and minimum fragmentation. Higher energy photons at 12.5 eV produce significant parent ion signal, but fragment intensity and other low mass ions are also enhanced. No matrix is added to enhance desorption, which is performed at peak power densities insufficient to directly produce ions, thus allowing observation of true VUV postionization mass spectra of antibiotic treated biofilms.
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Affiliation(s)
- Gerald L Gasper
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, USA
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13
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Akhmetov A, Moore JF, Gasper GL, Koin PJ, Hanley L. Laser desorption postionization for imaging MS of biological material. JOURNAL OF MASS SPECTROMETRY : JMS 2010; 45:137-45. [PMID: 20146224 PMCID: PMC2827192 DOI: 10.1002/jms.1716] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Vacuum ultraviolet single photon ionization (VUV SPI) is a soft ionization technique that has the potential to address many of the limitations of matrix-assisted laser desorption/ionization (MALDI) for imaging MS. Laser desorption postionization (LDPI) uses VUV SPI for postionization and is experimentally analogous to a MALDI instrument with the addition of a pulsed VUV light source. This review discusses progress in LDPI-MS over the last decade, with an emphasis on imaging MS of bacterial biofilms, analytes whose high salt environment make them particularly resistant to imaging by MALDI-MS. This review first considers fundamental aspects of VUV SPI including ionization mechanisms, cross sections, quantum yields of ionization, dissociation and potential mass limits. The most common sources of pulsed VUV radiation are then described along with a newly constructed LDPI-MS instrument with imaging capabilities. Next, the detection and imaging of small molecules within intact biofilms is demonstrated by LDPI-MS using 7.87 eV (157.6 nm) VUV photons from a molecular fluorine excimer laser, followed by the use of aromatic tags for detection of selected species within the biofilm. The final section considers the future prospects for imaging intact biological samples by LDPI-MS.
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Affiliation(s)
- Artem Akhmetov
- Department of Chemistry, m/c 111, University of Illinois at Chicago, Chicago, IL 60607-7061
| | - Jerry F. Moore
- MassThink, 500 East Ogden Avenue, Suite 200, Naperville, IL 60563-3281
| | - Gerald L. Gasper
- Department of Chemistry, m/c 111, University of Illinois at Chicago, Chicago, IL 60607-7061
| | - Peter J. Koin
- Department of Bioengineering, m/c 111, University of Illinois at Chicago, Chicago, IL 60607-7061
| | - Luke Hanley
- Department of Chemistry, m/c 111, University of Illinois at Chicago, Chicago, IL 60607-7061
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14
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Marksteiner M, Divochiy A, Sclafani M, Haslinger P, Ulbricht H, Korneev A, Semenov A, Gol'tsman G, Arndt M. A superconducting NbN detector for neutral nanoparticles. NANOTECHNOLOGY 2009; 20:455501. [PMID: 19822928 DOI: 10.1088/0957-4484/20/45/455501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We present a proof-of-principle study of superconducting single photon detectors (SSPD) for the detection of individual neutral molecules/nanoparticles at low energies. The new detector is applied to characterize a laser desorption source for biomolecules and allows retrieval of the arrival time distribution of a pulsed molecular beam containing the amino acid tryptophan, the polypeptide gramicidin as well as insulin, myoglobin and hemoglobin. We discuss the experimental evidence that the detector is actually sensitive to isolated neutral particles.
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