Ag Nanocluster/DNA Hybrids: Functional Modules for the Detection of Nitroaromatic and RDX Explosives

作者：Enkin Natalie; Sharon Etery; Golub Eyal; Willner Itamar^*

来源：Nano Letters, 2014, 14(8): 4918-4922.

DOI：10.1021/nl502720s

• Sensor
• nanoparticle
• luminescence
• TNT
• picric acid
• RDX

Luminescent Ag nanoclusters (NCs) stabilized by nucleic acids are implemented as optical labels for the detection of the explosives picric acid, trinitrotoluene (TNT), and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). The sensing modules consist of two parts, a nucleic acid with the nucleic acid-stabilized Ag NCs and a nucleic acid functionalized with electron-donating units, including L-DOPA, L-tyrosine and 6-hydroxy-L-DOPA, self-assembled on a nucleic acid scaffold. The formation of donor-acceptor complexes between the nitro-substituted explosives, exhibiting electron. acceptor properties, and the electron-donating sites, associated with the sensing modules, concentrates the explosives in close proximity to the Ag NCs. This leads to the electron-transfer quenching of the luminescence of the Ag NCs by the explosive molecule. The quenching of the luminescence of the Ag NCs provides a readout signal for the sensing process. The sensitivities of the analytical platforms are controlled by the electron-donating properties of the donor substituents, and 6-hydroxy-L-DOPA was found to be the most sensitive donor. Picric acid, TNT, and RDX are analyzed with detection limits corresponding to 5.2 X 10(-12) M, 1.0 x 10(-12) M, and 3.0 x 10(-12) M, respectively, using the 6-hydroxy-L-DOPA-modified Ag NCs sensing module.

• 出版日期2014-8