Simultaneous Determination Of Six Explosives In Dust And Water Samples By Liquid Chromatography Coupling With Atmospheric Pressure Chemical Ionization Mass Spectrometric

Along with the development of explosive production technique, organicexplosives were commonly used in military, industrial and civil areas. However, dueto its rapidity, convenience and causing huge damage, they were always utilized forterror attacks by terrorists. Nowadays, terror attacks become more inconspicuous anddiverse,and much harder to detect. So the qualitative determination of explosiveresidues in crime scenes is the important clue in solving crimes. At the same time,most of the explosives are toxic and carcinogenic, and it is important to monitor theexplosives concentration in the contaminated environment. Thus, the development ofa valid method for the determination of organic explosives is desirable.In this dissertation, a new method for the simultaneous determination of tracesix explosives including HMX,RDX,PETN,CE,NQ,TNT in spiked dust and watersamples was established. The method was based on the first extraction withASE(accelerated solvent extraction), followed by purification with GPC (GelPermeation Chromatography), and then determination with LC/APCI/MS. The resultswere as follows:Firstly, the method for the determination of explosives including HMX, RDX,PETN, CE, NQ,TNT by LC/APCI/MS was established. These six explosives werefirstly separated with LC, and then detected with MS after ionizing by APCI. It wasfound that HMX,RDX and NQ could be ionized with formic acid to formcorresponding adduct ions [M+HCOO]-. However, the other explosives, such asPETN,CE and TNT,couldn’t be ionized with formic acid. With LC/APCI/MS, the MDLs for HMX, RDX, PETN, CE, NQ and TNT were found to be0.78,1.44,1.69,0.77,1.06and1.72ng/mL,respectively.Secondly, the procedure for the pretreatment of the spiked dust and watersamples were developed based on the ASE and GPC methods. The tested explosiveswere firstly extracted from the spiked samples with ASE instrument, followed bypurification with GPC instrument. The experimental conditions for both ASE andGPC procedure were also optimized. Finally, under the optimum conditions, therecoveries of the six explosives in spiked dust and water samples were found to be49%~88.4%and46.7%~89.4%with the RSD of3.5%~10.3%and1.6%~10.5%,respectively.The newly developed method is valid, rapid and sensitive with excellentselection in the determination of these six organic explosives. It also could be appliedin analysis of explosives in the environment samples.