Smartphone-Assisted Sensing of Trinitrotoluene by Optical Array

Abstract

Here we report the design and fabrication of an array-based sensor, containing functionalized Carbon Dots, Bodipy’s and Naphthalimide probes, that shows high fluorescence emissions and sensitivity in the presence of low amounts of TNT explosive. In particular, we have fabricated the first sensor device based on an optical array for the detection of TNT in real samples by using a smartphone as detector. The possibility to use a common smartphone as detector leads to a prototype that can be also used in a real-life field application. The key benefit lies in the possibility of even a nonspecialist operator in the field to simply collect and send data (photos) to the trained artificial intelligence server for rapid diagnosis but also directly to the bomb disposal unit for expert evaluation. This new array sensor contains seven different fluorescent probes that are able to interact via noncovalent interactions with TNT. The interaction of each probe with TNT has been tested in solution by fluorescence titrations. The solid device has been tested in terms of selectivity and linearity toward TNT concentration. Tests performed with other explosives and other nitrogen-based analytes demonstrate the high selectivity for TNT molecules, thus supporting the reliability of this sensor. In addition, TNT can be detected in the range of 98 ng∼985 μg, with a clear different response of each probe to the different amounts of TNT.

Nanomaterials for Cortisol Sensing

“…In recent years, nanomaterials have been widely used for the chemical sensing of many species [ 32 , 33 , 34 , 35 ]. In particular, cortisol sensing by nanostructured species can be performed by different classes of nanosystems: gold nanoparticles, carbon nanoparticles, graphene oxide, metal nanoflowers, nanowires, nanoflakes, and metal nanorods.…”

Explosive and pollutant nitroaromatic sensing through a Cd(II) based ladder shaped 1D coordination polymer

“…There is a general perception among the common people about the explosive nature of TNT and through the print as well as electronic media we are more familiar with the term TNT [ [39] , [40] , [41] , [42] , [43] ], but 2,4,6 trinitrophenol by no means exhibits lesser potential as an explosive compared to TNT [ 44 , 45 ]. Therefore, designing a suitable chemosensor that can effectively detect TNP has extreme importance in the field of forensic science.…”

Rapid Detection of Trace Nitro-Explosives under UV Irradiation by Electronic Nose with Neural Networks

“…The artificial olfactory system, also called the electronic nose (E-nose), which consists of a sensor array with pattern recognition, has been developed to mimic the mammalian olfactory system for ETD. − Some kinds of sensor arrays have been designed, such as a multichannel colorimetric sensor array, , optoelectronic nose, − effect transistors, , and chemiresistors. , Zhao et al designed a dynamic multichannel colorimetric sensor array; the sensor array exhibited different absorption peaks at 456, 504, 552, 612, 754, and 906 nm; then 10 kinds of explosives can be discriminated based on it; and the detection limit achieved 1.5 μM . Askim et al reported an optoelectronic nose consisting of 40-element to distinguish several explosives and related compounds in the gas-phase, and the resulting 14 out of 16 groups achieved 100% accuracy .…”