Detection and identification of
environmental toxins, pesticides, explosives and landmines
This device can selectively detect and identify nitroaryl compounds, which may be found in pesticides and explosives, using polymer-encapsulated single-walled carbon nanotubes (SWNT).
The detection of compounds containing cyclic rings and nitrogen atoms can be desirable for a variety of applications. For example, nitroaryl-containing compounds are used in many relatively dangerous products such as pesticides and explosives. This system presents a device and method to effectively detect such compounds. Semiconducting SWNTs emit photoluminescence (PL) in the near-infrared (nIR) region of the electromagnetic spectrum. This PL is environmentally responsive, and it is made selectively responsive by specific polymer coatings adhered to the walls of the SWNT. The mechanisms of signal transduction include charge transfer interactions, which alter the PL intensity, and solvatochromic shifts, which shift the wavelength of the PL. These two responses constitute multiple modes of detection from the same nanotube emission band. A single nanotube can therefore respond to multiple analytes and produce different signals allowing the ability to distinguish between different analytes. Additionally, mixtures of several semiconducting SWNT species are used, wrapped by the same or different polymers, which result in analyte-dependent differentiable responses. The set of different responses can effectively obtain a molecular fingerprint for each analyte that elicits a response. The encapsulating polymer is used to create response selectivity in the nanotube, resulting in specific interactions with a finite number of analytes. The sensing occurs in real-time, allowing immediate reporting of detection events.
Allows identification of the hazardous
compounds , as well as their quantity
Allows remote real-time monitoring, ensuring the
safety of the user
immediate reporting of detection events