Highly Sensitive and Selective Dynamic Light-Scattering Assay for TNT Detection Using p-ATP Attached Gold Nanoparticle

Abstract

TNT is one of the most commonly used nitro aromatic explosives for landmines of military and terrorist activities. As a result, there is an urgent need for rapid and reliable methods for the detection of trace amount of TNT for screening in airport, analyzing forensic samples and environmental analysis. Driven by the need to detect trace amounts of TNT from environmental samples, this article demonstrates a label-free, highly selective and ultra sensitive para-aminothiophenol (p-ATP) modified gold nanoparticle based dynamic light scattering (DLS) probe for TNT recognition in 100 pico molar (pM) level from ethanol:acetonitile mixture solution. Due to the formation of strong π-donor–acceptor interaction between TNT and p-ATP, para-aminothiophenol attached gold nanoparticles undergo aggregation in the presence of TNT, which changes the DLS intensity tremendously. A detailed mechanism for significant DLS intensity change has been discussed. Our experimental results show that TNT can be detected quickly and accurately without any dye tagging in 100 pM level with excellent discrimination against other nitro compounds.

Sensitive Colorimetric Visualization of Perfluorinated Compounds Using Poly(ethylene glycol) and Perfluorinated Thiols Modified Gold Nanoparticles

“…12−26 However, the establishment of colorimetric assays for PFCs has not been reported yet. Actually, the applications of colorimetric assays based on Au NPs for environmental pollutants are scarce, and only very few colorimetric assays have been designed for TNT, 27,28 organophosphorus and carbamate pesticides, 29 and phthalates. 30 Selective isolation of fluorinated targets from convoluted mixtures has become increasingly popular using liquid−liquid separations, solid−liquid separations (such as fluorous solidphase extraction), and fluorous chromatography.…”

Functionalized CdSe/ZnS QDs for the Detection of Nitroaromatic or RDX Explosives

“…[ 17 ] Also, the aggregation of donor-modifi ed Au nanoparticles in the presence of the TNT acceptor substrate was used for the optical detection of TNT. [ 18 ] Quantum dots were, similarly, applied for the development of TNT [ 19 ] or RDX [ 20 ] luminescence biosensors. Anti-TNT antibodymodifi ed QDs were used as optical sensors for TNT using a competitive assay that employed a dye-labeled TNT as FRET quencher.…”

Dense aqueous colloidal gold nanoparticles prepared from highly concentrated precursor solution

“…If aggregates with diameters larger than 500 nm are allowed to form in a controlled fashion, their color varies systematically from pink through violet to blue [30][31][32][33]. However, the red color remained during formation of the gold nanoparticles (Fig.…”