A laser desorption ion-mobility increment spectrometer for detection of ultralow concentrations of nitro compounds. Instruments and Experimental Techniques Volume 56, Issue 3, May 2013, Pages 309-316

A compact instrument that implements for the first time a method for analyzing substances, in which laser desorption of analyzed molecules and laser ionization of an air sample are combined with the ionmobility increment spectroscopy, is described. Pulse radiation of the fourth harmonic of a portable (2.6 kg) GSGG: Cr3 : Nd3 laser (λ = 266 nm) is used. The detection limit of the developed laser desorption spectrometer of the ion-mobility increment is 40 pg for trinitrotoluene (TNT), and the linear dynamic range for TNT is 0.1-20.0 ng. The results from detection of nitro compounds are presented: trinitrotoluene, cyclotrimethylene trinitramine (RDX), and octogen (HMX). It is shown that laser desorption of nitro compounds from a metal is accompanied by their decomposition on the surface and emission of fragments. An ion signal is obtained for nitro compounds that were ionized outside the spectrometer. © 2013 Pleiades Publishing, Ltd.
Indexed keywords
Cyclotrimethylene trinitramine; Detection limits; Fourth harmonics; Laser desorption; Laser ionization; Linear dynamic ranges; Nitro compounds; Pulse radiation