ISSN:
0935-6304
Keywords:
Microbore capillary gas chromatography/mass spectrometry
;
Detection limits in scanning and non-scanning modes
;
Microchannel plate array detector
;
Ion counting vs. current amplification
;
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Identification and detection limits for scanning and non-scanning mass spectrometers are discussed. It is theoretically deduced and experimentally confirmed that these limits are on the low pico-and femtogram levels, respectively, when using conventional secondary electron multiplier-amplifier systems. The sensitivity can be increased at least tenfold by pulse-counting techniques, instead of current amplification, provided the chemical noise is sufficiently low. The potential advantages of a detection system for simultaneous ion detection in a significant mass range, for obtaining complete mass spectra in fast GC/MS analyses, are demonstrated. A double focusing mass spectrometer was constructed, using the well-proven Mattauch-Herzog principles. By application of an “electronic photoplate”, substance identification in the low femtogram range on a millisecond time scale, so far only accessible for single ion monitoring techniques, is feasible.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jhrc.1240121004
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