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Updated: Jan 3, 2026
A Method for Selecting Structure-switching Aptamers Applied to a Colorimetric Gold Nanoparticle Assay
Published on: February 28, 2015
Selective colorimetric detection of pentaerythritol tetranitrate (PETN) using arginine-mediated aggregation of gold
Zahra Taefi1, Forough Ghasemi2, M Reza Hormozi-Nezhad3
1Department of Chemistry, Sharif University of Technology, Tehran 111559516, Iran.
Abstract:
Detection of pentaerythritol tetranitrate (PETN) as an explosive has been of great interest because of public safety and military concerns. Here, we have presented a simple, selective and sensitive colorimetric method for direct detection of PETN. The gold nanoparticles (AuNPs) were first exposed to arginine which has primary amines in its structure. Electron deficient -NH2 groups from arginine could strongly interact with -NO2 groups of PETN as electron donors. Hydrogen bonding happens between the -NO2 group of PETN and -NH2 group of arginine molecules. Therefore, selective aggregation of AuNPs happened because of the donor-acceptor and hydrogen bonding interactions. Due to the aggregation, the color of reddish AuNPs turned to blue or purple depend on PETN concentration. A good linear relationship was achieved between the aggregation signal (absorbance ratio of A650/A520) of the probe and the concentration of PETN with a limit of detection of 0.169 μmol L-1. Furthermore, we have found that the developed probe can detect PETN in complex matrices of groundwater and soil samples.
