In the article by J. D. Reynolds and K. D. Cook in the March/April issue of the journal, there is an error in the second column of page 154. The last paragraph also approach this limiting value, they must do so at should read as follows. lower fluxes. This suggests that the current at which this li
Improving fast atom bombardment mass spectra: The influence of some controllable parameters on spectral quality
โ Scribed by Johnny D. Reynolds; Kelsey D. Cook
- Publisher
- Elsevier Science
- Year
- 1990
- Tongue
- English
- Weight
- 815 KB
- Volume
- 1
- Category
- Article
- ISSN
- 1044-0305
No coin nor oath required. For personal study only.
โฆ Synopsis
The relative effects of adjustable fast atom bombardment (FAB) parameters (choice of matrix, primary atom flux, and primary atom energy) on the appearance of FAB spectra (including signal-to-noise, signal-to-background, and signal-to-matrix ratios) of several organic dyes have been investigated. Beam-induced chemical damage is minimized by lowering the primary atom flux, by raising the primary atom energy, and by selecting a matrix with radical scavenging properties (e.g., m-nitrobenzyl alcohol). The relative importance in minimizing this chemical damage is choice of matrix > primary atom flux > (nominal) primary atom energy, but optimization of the parameters involves a trade-off between sensitivity and damage. The effect of these parameters on thermal damage (fragmentation) is much less. It can be concluded from comparison of the dyes that the extent of beam damage does not depend simply on the standard reduction potential of the analyte. (
๐ SIMILAR VOLUMES
When mass-analysed ion kinetic energy (MIKE) spectra are required to discriminate between isomeric ions formed under conditons of fast atom bombardment (FAB) in the ion source, severe interference may be observed. The interfering peaks in MIKE spectra obtained with a reversed-geometry instrument can