Surface chemical ionization mass spectrometry

Hansen, G.E.; Munson, Burnaby

doi:10.1021/ac50030a031

Cited by 57 publications

(29 citation statements)

References 23 publications

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“…A field desorption spectrum exhibits the MH+ ions as the base peak (25), but the cationized molecule such as (M + Na)+ was reported also as the dominant peak (2,26). Severe temperature (and heating rate) dependence of the mass spectrum has been reported (17,27). Therefore sucrose was examined by the LI method in order to clarify the characteristics of the method and to investigate the effects of a high electric field and additives.…”

Section: Methodsmentioning

confidence: 99%

Liquid ionization mass spectrometry of nonvolatile organic compounds

Tsuchiya¹,

Kuwabara²

1984

Anal. Chem.

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Characterlstlcs of a technique termed liquid ionization mass spectrometry for organic compounds are described. I n particular the use of additives (solvent, matrix, and reagent) for nonvolatile compounds and ease of sample handling are reported. Metastable argon atoms are used to lonlze compounds at atmospheric pressure. Samples are placed on a needle tip posltloned near an aperture ieadlng to the mass analyzer. The needle Is heated and a hlgh voltage (about 1 kV) is applied to the needle. Mass spectra obtained by this method showed ions characterlstlc of the molecular weight and the structure of the compounds. Liquld aikane(s) is a good matrix for nucleosides, while glycerol Is good for phosphatldyichoilnes. A minute amount of a reagent such as ethanoiamlne Increases the abundance of MH' Ions of sucrose, resulting in reproduclble mass spectra. The use of several reagents (e.g., D,O) for one compound Is suggested in order to obtain additional structural information. The advantages of the method are also described.In recent years, nonvolatile and/or thermally labile organic compounds have been successfully investigated by several soft methods of ionization such as field desorption (FD) ( I ) , laser desorption (2), plasma desorption (3), secondary ion mass spectrometry (SIMS) (4), fast atom bombardment (FAB) (5), atmospheric pressure ionization (API) (6, 7), and direct exposure techniques such as direct CI (8), in-beam E1 and CI (9, lo), emitter CI ( I l ) , and so on. There are, however, many compounds whose mass spectra cannot be obtained satisfactorily by using any of these techniques, especially when such compounds are present in an actual sample. The influence of coexisting compounds has to be investigated not only for obtaining a good mass spectrum of a compound but also for applying the rapidly developing method termed mass spectrometry/mass spectrometry (MS/MS) (12) to nonvolatile compounds.Many efforts to combine a liquid chromatograph with a mass spectrometer (LC/MS) have been made in recent years (6, 13-16) and commercial instruments are now available. There is, however, still difficulty in measuring nonvolatile compounds reliably by LC/MS combinations presently available. Therefore, it is important to understand the mechanism of ionization and desorption (1 7) and the effects of experimental parameters in order to develop new techniques in mass spectrometry.We have developed a method which we call "liquid ionization" (referred to as LI in this paper) for ionizing organic compounds present as a liquid or in aolution at atmospheric pressure (1419). Thus, the method (LI) is a variation of the atmospheric pressure ionization (API) developed by Horning and his co-workers (13). The main differences in the principles of the method (LI) from that of Horning and other API methods (6, 7) involve the technique of ionization and the sample introduction system. There are two techniques of ionization in the LI method, one of which utilizes proton transfer reactions from cluster ions of water, (H20),Ht, to sample mol...

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Section: Methodsmentioning

confidence: 99%

Liquid ionization mass spectrometry of nonvolatile organic compounds

Tsuchiya¹,

Kuwabara²

1984

Anal. Chem.

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“…Instrument development in the cotter laboratory at the Johns Hopkins university School of Medicine began in the late 1970s amidst a flurry of interest in the so-called rapid-heating methods as alternatives to field desorption 1 for the mass spectral analysis of non-volatile compounds. these techniques included the direct electron ionization (EI) method of McLafferty and Baldwin in 1973, 2 flash volatilization by Doyle Daves in 1977, 3 in-beam EI of ohashi 4 and direct chemical ionization (CI) by Hansen and Munson in 1978 5 and the direct exposure CI method from cotter and fenselau. 6,7 All of these studies were motivated by the suggestion of Buehler and friedman 8 that a crossover in the Arrhenius plots for the decomposition vs desorption of non-volatiles was such that rapid heating to a very high temperature would render the desorption process more favorable.…”

Section: Journal Of Mass Spectrometrymentioning

confidence: 99%

Time-of-Flights and Traps: From the Histone Code to Mars

Cotter

Swatkoski

Becker

et al. 2010

Eur J Mass Spectrom (Chichester)

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Two very different analytical instruments are featured in this perspective paper on mass spectrometer design and development. The first instrument, based upon the curved-field reflectron developed in the Johns Hopkins Middle Atlantic Mass Spectrometry Laboratory, is a tandem time-of-flight mass spectrometer whose performance and practicality are illustrated by applications to a series of research projects addressing the acetylation, deacetylation and ADP-ribosylation of histone proteins. The chemical derivatization of lysine-rich, hyperacetylated histones as their deuteroacetylated analogs enables one to obtain an accurate quantitative assessment of the extent of acetylation at each site. Chemical acetylation of histone mixtures is also used to determine the lysine targets of sirtuins, an important class of histone deacetylases (HDACs), by replacing the deacetylated residues with biotin. Histone deacetylation by sirtuins requires the co-factor NAD+, as does the attachment of ADP-ribose. The second instrument, a low voltage and low power ion trap mass spectrometer known as the Mars Organic Mass Analyzer (MOMA), is a prototype for an instrument expected to be launched in 2018. Like the tandem mass spectrometer, it is also expected to have applicability to environmental and biological analyses and, ultimately, to clinical care.

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“…In the 1980s, “desorption to gas phase by rapid heating” gained attention through the efforts of several groups that had obtained some encouraging results. These include Franz Röllgen6, 7 of Germany, Mamoru Ohashi8 of Japan, and Louis Friedman,9 Don Hunt,10 Burnaby Munson,11 and Robert Cotter12 of the USA. A simple description of the principle is depicted in Figure 12.…”

Section: Ionization Technologymentioning

confidence: 99%

The Origin of Macromolecule Ionization by Laser Irradiation (Nobel Lecture)

Tanaka

2003

Angew Chem Int Ed

172

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Without fragmentation: The mass spectrometric analysis of biological macromolecules can be achieved without fragmentation of the parent molecule by using the technique of soft laser (matrix‐assisted laser desorption/ionization (MALDI; see scheme, UFMP=ultrafine metal‐powder matrix). The development of this technique was greatly influenced by the work of Koichi Tanaka for which he was awarded the Nobel Prize for Chemistry in 2002.

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Surface chemical ionization mass spectrometry

Cited by 57 publications

References 23 publications

Liquid ionization mass spectrometry of nonvolatile organic compounds

Liquid ionization mass spectrometry of nonvolatile organic compounds

Time-of-Flights and Traps: From the Histone Code to Mars

The Origin of Macromolecule Ionization by Laser Irradiation (Nobel Lecture)

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