✦ LIBER ✦

Field desorption mass spectra of the cyclic depsipeptide valinomycin: Energy deficits in ion formation

✍ Scribed by Margaret M. Sheil; Peter J. Derrick

Publisher: John Wiley and Sons
Year: 1992
Tongue: English
Weight: 532 KB
Volume: 27
Category: Article
ISSN: 1076-5174
DOI: 10.1002/oms.1210271008

No coin nor oath required. For personal study only.

✦ Synopsis

The formation of ions of the cyclic depsipeptide valinomycin by field desorption has been investigated in detail. The ratio of molecular ions M+' to protonated molecules (M + HI+ has been found to be independent of emitter heating current and the nature of particular additives to the solution. In contrast, the abundance of sodiated [M + Nal+ ions compared with the molecular ions and protonated molecules was strongly dependent on the heating current. The energy deficits for M+' and [ M + HI + ions were similar, but were significantly larger than the energy deficits for IM + Nal + ions. There appeared to be no relationship between the abundance of cationized species generated by field desorption and the selectivity of valinomycin for monovalent cations in solution. The implications of these observations for the mechanism of field desorption are discussed.

📜 SIMILAR VOLUMES

Four-sector tandem mass spectrometry: A

Four-sector tandem mass spectrometry: A comparison of the molecular and quasi-molecular ions of the cyclic depsipeptide valinomycin formed using electron impact, chemical ionization, fast atom bombardment, field desorption and electrospray lonizatfion

✍ Jonathan M. Curtis; Caroline D. Bradley; Peter J. Derrick; Margaret M. Sheil 📂 Article 📅 1992 🏛 John Wiley and Sons 🌐 English ⚖ 606 KB

Four-sector tandem mass spectra of the molecular and quasi-molecular ions of the cyclic depsipeptide valinomycin (RMM 1110.6) were compared. Electron impact (EI), chemical ionization (CI), fast atom bombardment (FAB), field desorption (FD) and electrospray ionization were used to create M", (M + HI'

Formation of complexes with divalent ion

Formation of complexes with divalent ions as a means of extending the mass scale in field desorption mass spectrometry

✍ Gordon W. Wood; Wing Fung Sun 📂 Article 📅 1980 🏛 John Wiley and Sons 🌐 English ⚖ 182 KB 👁 2 views

Fragment-molecule adduct ion formation i

Fragment-molecule adduct ion formation in the mass spectra of cyclic N-acetylamines and related nitramines

✍ Elizabeth P. Burrows 📂 Article 📅 1991 🏛 John Wiley and Sons 🌐 English ⚖ 428 KB

Mass spectra of seven related N-heterocyclics, introduced by direct exposure probe, were determined in electron impact (EI) and positive-and negative-ion chemical ionization (PCI and NCI) modes. Proton adducts were the predominant molecular ion species in the EI and PCI modes. In addition, a variety

Field-induced Ion Chemistry Leading to t

Field-induced Ion Chemistry Leading to the Formation of (M-2nH)+· and (2M-2mH)+· Ions in Field Desorption Mass Spectrometry of Saturated Hydrocarbons

✍ Klesper, G.; Röllgen, F. W. 📂 Article 📅 1996 🏛 John Wiley and Sons 🌐 English ⚖ 500 KB

The formation of [ M -2HI" ions has been reported in the field desorption mass spectrometry of saturated hydrocarbons. It is shown that these ions predominantly have an alkene structure and that a field-induced ion chemistry in multimolecular or condensed layers produce [M -2nHI + ' and [2M -2rnH]+'