title: Electrochemiluminescence detection of TNT by resonance energy transfer through the formation of a TNT-amine complex.
abstract: 2,4,6-Trinitrotoluene (TNT) is a widely used nitroaromatic explosive with significant detrimental effects on the environment and human health. Its detection is of great importance. In this study, both electrochemiluminescence (ECL)-based detection of TNT through the formation of a TNT-amine complex and the detection of TNT through electrochemiluminescence resonance energy transfer (ECRET) are developed for the first time. 3-Aminopropyltriethoxysilane (APTES)-modified [Ru(phen)3](2+) (phen=1,10-phenanthroline)-doped silica nanoparticles (RuSiNPs) with uniform sizes of (73±3) nm were synthesized. TNT can interact with APTES-modified RuSiNPs through charge transfer from electron-rich amines in the RuSiNPs to the electron-deficient aromatic ring of TNT to form a red TNT-amine complex. The absorption spectrum of this complex overlaps with the ECL spectrum of the APTES-modified RuSiNPs/triethylamine system. As a result, ECL signals of the APTES-modified RuSiNPs/triethylamine system are turned off in the presence of TNT owing to resonance energy transfer from electrochemically excited RuSiNPs to the TNT-amine complex. This ECRET method has been successfully applied for the sensitive determination of TNT with a linear range from 1×10(-9) to 1×10(-6) M with a fast response time within 1 min. The limit of detection is 0.3 nM. The method exhibits good selectivity towards 2,4-dinitrotoluene, p-nitrotoluene, nitrobenzene, phenol, p-quinone, 8-hydroxyquinoline, p-phenylenediamine, K3[Fe(CN)6], Fe(3+), NO3(-), NO2(-), Cr(3+), Fe(2+), Pb(2+), SO3(2-), formaldehyde, oxalate, proline, and glycine.
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (P.R. China), Fax: (+86) 431-8526-2747; Graduate University of the Chinese Academy of Sciences, Beijing (P.R. China).
authors.forename: Wenjing
authors.initials: W
authors.lastname: Qi
authors.forename: Min
authors.initials: M
authors.lastname: Xu
authors.forename: Lei
authors.initials: L
authors.lastname: Pang
authors.forename: Zhongyuan
authors.initials: Z
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Saadat
authors.initials: S
authors.lastname: Majeed
authors.forename: Guobao
authors.initials: G
authors.lastname: Xu
mesh_terms: D000588:Amines / Q000737:chemistry*; D056831:Coordination Complexes / Q000737:chemistry; D053834:Explosive Agents / Q000032:analysis* / Q000737:chemistry; D031541:Fluorescence Resonance Energy Transfer; D008163:Luminescent Measurements; D053758:Nanoparticles / Q000737:chemistry; D010316:Particle Size; D011437:Propylamines; D012428:Ruthenium / Q000737:chemistry; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D014303:Trinitrotoluene / Q000032:analysis* / Q000737:chemistry
chemical_list: D000588:Amines; D056831:Coordination Complexes; D053834:Explosive Agents; D011437:Propylamines; D012821:Silanes; D014303:Trinitrotoluene; D012822:Silicon Dioxide; D012428:Ruthenium; C477625:amino-propyl-triethoxysilane
keywords: analytical methods; charge transfer; electrochemiluminescence; explosives; resonance-energy transfer