Proton transfer mass spectrometry of underivatized peptides

Beuhler, R. J.; Flanigan, Everett; Greene, Lewis Joel; Friedman, L.

doi:10.1021/bi00721a030

Cited by 38 publications

(14 citation statements)

References 12 publications

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“…These higher mass ions decreased in relative abundance with increasing repeller voltage; so we consider that they result in part from gaseous ion-molecule reactions. Table I1 shows the in-beam/CI spectrum of arginine obtained at 260 "C. As mentioned earlier, it is quite similar to the rapid heating spectrum obtained using a heating rate of 5 "C/s (9,10).…”

Section: Resultssupporting

confidence: 70%

Surface chemical ionization mass spectrometry

Hansen¹,

Munson²

1978

Anal. Chem.

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1'0DC129 Vlcm Torr %TIC 3 0 30 (155.,,,,,'" 0 1 0 3 Torr % T I C 2 0 '0 4 0 60 8 3 803 2 0 ETHYL BUTYRATE 2 o L _ _ . d 1 0 43 60 8 0 1 0 3 1 2 0 "ROPYL PRCP OluA-E Flgure 3.Water CI spectra of ethyl butyrate and propyl propionate obtained in the drift-tube CI source with water reagent gas at 110 OC and 0.103 Torr. The drift field strength was 129 Vkm-Torr, sufficient to produce substantial amounts of fragmentation characteristic of these two structural isomers preferential solvation of the product ion favors formation of RCOOH2+-OH2 from (RCOOR')H+.OH, over formation of RCOOH2+ from (RCOOH')H+. Inasmuch as the origins and analytical utility of all of the various ions observed in the CI spectra of esters have been discussed extensively in previous work (6,8,14), there is no ease of identifying esters from their water CI spectra at high E / P in the drift tube source, Figure 3 compares the spectra of ethyl butyrate and propyl propionate at 129 V/cm-Torr. The MH+ ions at m / e 117 are present for both esters, but none of the other peaks are identical. The fragment ions in ethyl butyrate are R+ ( m / e 43), RCO' ( m / e 711, RCOOH2+ ( m / e 89), and RCOOH2+.0H2 ( m / e 107), while the fragment ions \ need to repeat that information here. As an example of the The use of "in-beam" sample introduction to obtain chemical ionization (CI) mass spectra of thermally labile compounds and salts of low volatilHy is descrlbed. Samples are introduced on the surface of Teflon tubing and the effects of changing the sample position in the source are shown. The time and temperature dependence of some CI mass spectra are shown.

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Section: Resultssupporting

confidence: 70%

Surface chemical ionization mass spectrometry

Hansen¹,

Munson²

1978

Anal. Chem.

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“…(2) Friedman has suggested that the nonequilibrium evaporation of intact molecules is enhanced by the lower intermolecular forces present when the sample is in the form of a thin film. 24,25 In our case the volatility appears to be increased by coating the sample on the Vespel@ surface, rather than relying upon vaporization of molecules from crystals located in a sample holder outside the source. It is also possible that the use of an 'inert' material such as Vespel@ aids the desorption process.…”

Section: Evaluation Of the Role Of The Heating Rate In The Ionizationmentioning

confidence: 92%

The effects of heating rate and sample size on the direct exposure/chemical ionization mass spectra of some biological conjugates

Cotter

Fenselau

1979

Biol. Mass Spectrom.

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A direct exposure probe has been used to obtain mass spectra of underivatized guanosine, deoxyguanosine, sucrose and the p-nitrophenyl-beta-D-glucuronide. In all cases, a protonated molecular ion is produced with good relative abundance. The effects of heating rate and sample size on the production of the [MH]+ ION ARE EXAMINED IN DETAIL FROM TOTAL ION ANd single ion currents produced during rapid, repetitive scanning of the spectra after probe insertion. From this data we conclude that protonated molecular ions are produced as a result of the enhanced volatility of neutral molecules on the probe surface, followed by chemical ionization, and not by surface ionization.

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“…36 The system falls between conventional direct insertion probe and desorption CI in its ability to handle thermally labile and low volatility compounds.37 Sensitivity is difficult to define since it is dependent on the compounds studied and the form of the high performance liquid chromatographic peaks. In general it appears to be comparable with the direct introduction of a portion of the high performance liquid chromatographic eluant approach, in that full spectra are obtained in the on-line mode from upwards of 100 ng of sample injected on the high performance liquid chromatograph and in the selected ion monitoring mode high pg-low ng samples can be handled.…”

Section: Removal Of Solvent From High Performance Liquid Chromatograpmentioning

confidence: 99%

Combined high performance liquid chromatography mass spectrometry

Games¹

1981

Biol. Mass Spectrom.

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Combined gas chromatography mass spectrometry, because of its ability to provide both high sensitivity and specificity, has become a vital technique for the identification and quantitation of natural and synthetic chemicals in a wide variety of areas. Unfortunately, a very large number of organic compounds are not directly amenable to gas chromatography since they are thermally labile and/or of low volatility. Chemical modification of compounds of interest can assist in some cases, but it is not universally applicable. High performance liquid chromatography has been increasingly utilized for studies of compounds of these types since heat is not usually involved in the analysis. Combined liquid chromatography mass spectrometry would lend a new dimension to these studies, enabling the separating ability of the liquid chromatograph to be combined with the sensitivity and specificity of the mass spectrometer. Approaches to liquid chromatography mass spectrometry are discussed. Using examples from our liquid chromatographic mass spectrometric studies of natural compounds, drugs and pesticides, the current abilities of such systems to identify and quantify natural and synthetic chemicals present in a complex matrix of other chemicals are described.

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Proton transfer mass spectrometry of underivatized peptides

Abstract: Proton transfer spectra of the following underivatized peptides have been studied in a tandem mass spec-

Cited by 38 publications

References 12 publications

Surface chemical ionization mass spectrometry

Surface chemical ionization mass spectrometry

The effects of heating rate and sample size on the direct exposure/chemical ionization mass spectra of some biological conjugates

Combined high performance liquid chromatography mass spectrometry

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