Inkjet-Printed Silver Nanoparticle Paper Detects Airborne Species from Crystalline Explosives and Their Ultratrace Residues in Open Environment

Abstract

An electronic nose can detect highly volatile chemicals in foods, drugs, and environments, but it is still very much a challenge to detect the odors from crystalline compounds (e.g., solid explosives) with a low vapor pressure using the present chemosensing techniques in such way as a dog's olfactory system can do. Here, we inkjet printed silver nanoparticles (AgNPs) on cellulose paper and established a Raman spectroscopic approach to detect the odors of explosive trinitrotoluene (TNT) crystals and residues in the open environment. The layer-by-layer printed AgNP paper was modified with p-aminobenzenethiol (PABT) for efficiently collecting airborne TNT via a charge-transfer reaction and for greatly enhancing the Raman scattering of PABT by multiple spectral resonances. Thus, a Raman switch concept by the Raman readout of PABT for the detection of TNT was proposed. The AgNPs paper at different sites exhibited a highly uniform sensitivity to TNT due to the layer-by-layer printing, and the sensitive limit could reach 1.6 × 10(-17) g/cm(2) TNT. Experimentally, upon applying a beam of near-infrared low-energy laser to slightly heat (but not destruct) TNT crystals, the resulting airborne TNT in the open environment was probed at the height of 5 cm, in which the concentration of airborne species was lower than 10 ppt by a theoretical analysis. Similarly, the odors from 1.4 ppm TNT in soil and 7.2, 2.9, and 5.7 ng/cm(2) TNT on clothing, leather, and envelope, respectively, were also quickly sensed for 2 s without destoying these inspected objects.

A positively charged silver nanowire membrane for rapid on-site swabbing extraction and detection of trace inorganic explosives using a portable Raman spectrometer

“…requires analytical methods with high speed and sensitivity [2,3]. Numerous analytical methods, such as laser photoacoustic spectroscopy [4], fluorescence [5][6][7], surface-enhanced Raman spectroscopy (SERS) [8,9], nano-electrical devices [10], mass spectrometry, ion mobility spectroscopy, and X-ray imaging [11] have been used or proposed as suitable methods for the detection and quantification of nitro-explosives, such as 2,4,6-trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), cyclo-1,3,5-trimethylene-2,4,6-trinitramine (RDX) and 2,4,6-trinitrophenol (TNP) et al Capillary electrophoresis (CE) [12], ion chromatography (IC) [13], electrospray ionization mass spectrometry (ESI-MS) [14], and electrospray ionization ion mobility spectrometry (ESI-IMS) [15] have been employed to detect characteristic ions of inorganic explosives, such as ClO 4 − , ClO 3 − , or NO 3 − [16,17], which are known for their high stability and non-volatility. Recently, the capability of thermal desorption ion mobility spectrometry (TD-IMS) for the on-site sensitive detection of typical nitro-explosives such as TNT and RDX has been demonstrated.…”

Fabrication of cube-like Fe3O4@SiO2@Ag nanocomposites with high SERS activity and their application in pesticide detection

“…The enormous SERS enhancement effect has enabled this technology to be widely applied in biology, medicine pharmacy, environmental monitoring, national security and other fields over the decades (Ye et al 2012;Zong et al 2012;Yang et al 2014;Wang et al 2014a). Recently, the combination of magnetic materials and noble metals as SERS substrates is of special interest because the as-obtained magnetic nanocomposites can simultaneously attain dual functions of both fast magnetic response and local surface plasmon resonance.…”

Nanomaterials for luminescence detection of nitroaromatic explosives

“…Although detection techniques for explosive materials have been highly developed and employed, such as liquid and gas chromatography mass spectrometry (LC/GC-MS) [4], Fourier-transform infrared (FTIR), surface-enhanced Raman spectroscopy (SERS) [5,6], ion-mobility spectrometry, enzymatic assays, optodes and electrochemistry [7], they are confined to sophisticated instruments in the laboratory and time-consuming with a certain cost, and they are not conveniently applied to in-field and real-time detection of explosives [8]. Reliable methods for the rapid, sensitive determination of nitroaromatic explosives are in great demand.…”