Applications of thermospray liquid chromatography/mass spectrometry

Abstract

Thermospray liquid chromatography/mass spectrometry using a double-focusing magnetic sector mass spectrometer has been studied. The quality of the thermospray mass spectra were often a function of the solvent mixture used, and use of gradients affected the quality of some thermospray mass spectra. High resolution mass measurements using peak matching gave excellent results for pure compounds and mixtures which did not have 13C isotope interferences. When 3C isotope interference was a problem high-performance liquid chromatographic separation together with magnetic scanning was used.

Use of protic and aprotic solvents of high volatility as matrices in analytical low-temperature fast-atom bombardment mass spectrometry

“…Initially, glycerol was the only matrix used 5 but before long other organic solvents of low volatility were found to yield improved spectra; among them 3-nitrobenzyl alcohol (3-NBA) 6-8 2-nitrophenyl octyl ether (2-NPOE), 6,9 paraffin, [10][11][12] sulpholane, [13][14][15] concentrated sulfuric acid 16 and others. 9,17,18 Since that time several reviews on the matrix aspect [19][20][21][22][23] and on the processes of desorption and ion formation [24][25][26] under FAB conditions have appeared. It is commonly accepted that a good matrix for FAB-MS has to meet the following requirements: 19,22 1) The samples must be soluble in the matrix, otherwise addition of co-solvents like dimethyl formamide (DMF) or dimethyl sulphoxide (DMSO) becomes necessary.…”

“…9,17,18 Since that time several reviews on the matrix aspect [19][20][21][22][23] and on the processes of desorption and ion formation [24][25][26] under FAB conditions have appeared. It is commonly accepted that a good matrix for FAB-MS has to meet the following requirements: 19,22 1) The samples must be soluble in the matrix, otherwise addition of co-solvents like dimethyl formamide (DMF) or dimethyl sulphoxide (DMSO) becomes necessary. 2) Only low vapor pressure solvents can be easily used.…”

Negative-ion low-temperature fast-atom bombardment mass spectrometry of monomeric and dimeric [60]fullerene compounds

“…7 Thus, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) represents the only mass spectrometric technique for most of the dimers so far. 4,[8][9][10][11][12][13] However, MALDI-TOFMS exhibits limitations in the case of the rather unstable C 120 5,6 and it does not provide the unambigous identification of C 120 OS 13 because this cannot be distinguished from C 120 O 3 under these conditions.Good solubility of the sample in the matrix is a prerequisite for FAB-MS. [17][18][19][20] Consequently, the problems with FAB-MS arise from the extremely low solubility of the [60]fullerene dimers in conventional FAB matrices. Recently, a technique was introduced which employs volatile solvents, e.g.…”