Analytical Facets of Gas Phase Ion Reactions

Improvements in threshold applications of IMS have arisen from improved sampling methods, more sensitive and rugged instrumentation, and better data-processing techniques. These are seen with advances in the detection of explosives with handheld as well as with fixed or stationary analyzers. Parallel advances have occurred with instrumentation and procedures requiring quantitative determinations. These have occurred with the increased availability of drift tubes that exhibit fast response, low memory effects, and reproducible delivery of sample to the ion source. Together, these applications have resulted in enhanced precision, sensitivity, and linear range compared with previous generations of analyzers. 

Measurements with ion mobility methods depend on the identity of the gas, the ion, and the interactions of this ion with the supporting gas atmosphere. When collision frequencies are large and ions are often found at thermal energies, gaseous ions are influenced fundamentally and strongly by a range of parameters. Virtually every 

At a level of practical or routine use, mobility spectrometers provide high value in analytical chemistry with control of experimental parameters made through good engineering and measurement procedures. This performance is good enough that lives of soldiers depend on the reliability of in-field findings with handheld version of ion mobility instruments, and desktop instruments are central to international commercial aviation security. 

Beegle, L.W. Kanik, L, Investigation of drift gas selectivity in high resolution ion mobility spectrometry with mass spectrometry detection, J. Am. Soc. Mass Spectrom. 2002, 13, 300-307. 

Revercomb, H.E. Mason, E. A., Theory of plasma chromatography/gaseons electrophoresis, Rev. Anal. Chem. 1975,47(7), 970-983. 

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