title: Trace Detection of RDX, HMX and PETN Explosives Using a Fluorescence Spot Sensor.
abstract: 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and pentaerythritol tetranitrate (PETN), the major components in plastic explosives, pose a significant threat to public safety. A quick, sensitive, and low-cost detection method for these non-volatile explosives is eagerly demanded. Here we present a fluo-spot approach, which can be employed for in situ detection of trace amount of explosives. The sensor molecule is a charge-transfer fluorophore, DCM, which is strongly fluorescent in its pristine state, but non-fluorescent after the quick reaction with NO2· (or NO2(+)) generated from the UV photolysis of RDX, HMX (or PETN). When fabricated within silica gel TLC plate, the fluo-spot sensor features high sensitivity owing to the large surface area and porous structure of the substrate. The sensor reaction mechanism was verified by various experimental characterizations, including chromatography, UV-Vis absorption and fluorescence spectroscopy, MS and (1)H NMR spectrometry. The fluo-spot also demonstrated high selectivity towards RDX, HMX and PETN, as no significant fluorescence quenching was observed for other chemical compounds including common nitro-aromatic explosives and inorganic oxidative compounds. The DCM sensor can also be used as an economical spray kit to directly spot the explosives by naked eyes, implying great potential for quick, low-cost trace explosives detection.
authors.affiliation: Nano Institute of Utah and Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA.
authors.forename: Chen
authors.initials: C
authors.lastname: Wang
authors.affiliation: Nano Institute of Utah and Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA.
authors.forename: Helin
authors.initials: H
authors.lastname: Huang
authors.affiliation: Nano Institute of Utah and Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA.
authors.forename: Benjamin R
authors.initials: BR
authors.lastname: Bunes
authors.affiliation: Nano Institute of Utah and Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA.
authors.forename: Na
authors.initials: N
authors.lastname: Wu
authors.affiliation: Nano Institute of Utah and Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA.
authors.forename: Miao
authors.initials: M
authors.lastname: Xu
authors.affiliation: Nano Institute of Utah and Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA.
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Yang
authors.affiliation: Key Laboratory of Colloid and Interface Chemistry, Shandong University, Ministry of Education, Jinan 250100, PR China.
authors.forename: Li
authors.initials: L
authors.lastname: Yu
authors.affiliation: Nano Institute of Utah and Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA.
authors.forename: Ling
authors.initials: L
authors.lastname: Zang
mesh_terms: D001392:Azocines / Q000032:analysis*; D002623:Chemistry Techniques, Analytical; D053834:Explosive Agents / Q000032:analysis*; D005453:Fluorescence; D010417:Pentaerythritol Tetranitrate / Q000032:analysis*; D014227:Triazines / Q000032:analysis*; D014466:Ultraviolet Rays
chemical_list: D001392:Azocines; D053834:Explosive Agents; D014227:Triazines; D010417:Pentaerythritol Tetranitrate; C007950:octogen; C009160:cyclonite