US EPA

864529 

Journal Article 

Photofragmentation of nitro-based explosives with chemiluminescence detection 

Monterola, MP; Smith, BW; Omenetto, N; Winefordner, JD 

2008 

Yes 

Analytical and Bioanalytical Chemistry
ISSN: 1618-2642
EISSN: 1618-2650 

SPRINGER HEIDELBERG 

HEIDELBERG 

391 

7 

2617-2626 

English 

18551285 

10.1007/s00216-008-2177-7 

WOS:000258083900025 

A simple, fast, reliable, sensitive and potentially portable explosive detection device was developed employing laser photofragmentation (PF) followed by heterogeneous chemiluminescence (CL) detection. The PF process involves the release of NO(x(x = 1,2)) moieties from explosive compounds such as TNT, RDX, and PETN through a stepwise excitation-dissociation process using a 193 nm ArF laser. The NO(x(x = 1,2)) produced upon PF is subsequently detected by its CL reaction with basic luminol solution. The intensity of the CL signal was detected by a thermoelectrically cooled photomultiplier tube with high quantum efficiency and negligible dark current counts. The system was able to detect trace amounts of explosives in various forms in real time under ambient conditions. Detection limits of 3 ppbv for PETN, 2 ppbv for RDX, and 34 ppbv for TNT were obtained. It was also demonstrated that the presence of PETN residue within the range of 61 to 186 ng/cm(2) can be detected at a given signal-to-background ratio of 10 using a few microjoules of laser energy. The technique also demonstrated its potential for the direct analysis of trace explosive in soil. An LOD range of 0.5-4.3 ppm for PETN was established, which is comparable to currently available techniques. 

nitro-based explosives; photofragmentation; chemiluminescence; TNT; RDX; PETN