The increased use of peroxide-based explosives (PBEs) in criminal and terrorist activity has created a demand for continued
innovation in the detection of these agents. This review provides an update to a previous 2006 review on the detection of
PBEs, with a focus in this report on luminescence and fluorescence methods, infrared and Raman spectroscopy, mass spectrometry,
and electrochemical techniques. Newer developments in gas chromatography and high performance liquid chromatography methods
are also discussed. One recent trend that is discussed is an emphasis on field measurements through the use of portable instruments
or portable assay formats. An increase in the use of infrared spectroscopy and mass spectrometry for PBE analysis is also
noted. The analysis of triacetone triperoxide has been the focus in the development of many of these methods, although hexamethylene
triperoxide diamine has received increased attention in PBE detection during the last few years.
"Liquid materials such as hazardous liquid fuel, liquid explosives and precursor chemicals are deserved special attention by security screening. Many different approaches have been proposed to address the challenge of liquid identification for security screening, including Raman scattering , gas chromatography/mass spectrometry , magnetic resonance  , terahertz spectroscopy , Hilbert spectroscopy  and ion mobility spectrometry . Unfortunately, some of these highly sensitive methods are expensive and required sophisticated instrumentation ; furthermore, some approaches require direct contact with the liquid samples generally stored in containers that cannot be opened routinely for inspection. "
[Show abstract][Hide abstract] ABSTRACT: Application of the energy dispersive X-ray scattering (EDXRS) for the identification of pure liquid materials was reported for the first time. Three liquid systems of primary alcohols, benzene homologues and chloromethanes were carefully probed and the scattering spectra were described. On the basis of the different structures and compositions of these compounds, the scattering profiles of all media exhibit characteristic shapes, which implies that the EDXRS profile is unique to the specific material and significant differences of profiles amongst various liquid substances can be observed. Moreover, the result suggests that non-invasive EDXRS approach would be quite promising in the field of liquid discrimination/recognition.
[Show abstract][Hide abstract] ABSTRACT: Energy dispersive X-ray scattering (EDXRS) has been successfully applied for the identification of liquid materials for the first time. Three liquid systems of primary alcohols, ketones compounds and acids are carefully investigation and the scattering spectra are described. Based on structural and compositional differences of compounds, the scattering profiles of all samples exhibit characteristic shapes, indicating that EDXRS profile is unique to each specific liquid material. These findings imply that EDXRS would be promisingly applied as a non-invasive inspection for liquid identification.
[Show abstract][Hide abstract] ABSTRACT: The two members of peroxide-based explosives, triacetone triperoxide (TATP) and hexamethylene triperoxide diamine (HMTD), can be manufactured from readily accessible reagents, and are difficult to detect by conventional analytical methods. TATP and HMTD were securely synthesized, taken up with acetone, hydrolyzed with 4 M HCl to hydrogen peroxide, the acidic solution containing H(2)O(2) was neutralized, and assayed by the copper(II)-neocuproine spectrophotometric method. The chromophore of the reaction was the Cu(I)-neocuproine chelate responsible for light absorption at 454 nm. The molar absorptivity (epsilon) of the method for TATP and HMTD was 3.45 x 10(4) and 4.68 x 10(4) L mol(-1) cm(-1), respectively. The TATP recovery from a synthetically contaminated loamy clay soil was 91-99%. The colorimetric method was also applied to a Cu(ii)-neocuproine-impregnated polymeric Nafion membrane sensor developed for the first time in this work for peroxide explosive assay. The absorbance-concentration response was perfectly linear, and the limit of detection (LOD) of the procedure for both TATP and HMTD was approximately 0.2 mg L(-1). Neither common soil ions (Ca(2+), K(+), Cl(-), SO(4)(2-), Mg(2+) and NO(3)(-)) at 100-fold amounts nor military-purpose nitro-explosives of TNT, RDX, and PETN at 10-fold amounts interfered with the proposed assay. Active oxygen constituents of laundry detergents (perborates and percarbonates), which normally interfered with the assay, could easily be separated from the analytes by solubility differences. The method was statistically validated against standard reference methods of TiOSO(4) colorimetry and GC-MS.
The Analyst 08/2010; 135(8):2085-91. DOI:10.1039/b925653a · 4.11 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.