Electrochemical Determination of TNT, DNT, RDX, and HMX with Gold Nanoparticles/Poly(Carbazole-Aniline) Film–Modified Glassy Carbon Sensor Electrodes Imprinted for Molecular Recognition of Nitroaromatics and Nitramines

Abstract

Since nitroaromatic- and nitramine-type energetic materials, mostly arising from military activities, are persistent pollutants in soil and groundwater, on-site sensing of these hazardous chemicals has gained importance. A novel electrochemical sensor was designed for detecting nitroaromatic- and nitramine-type energetic materials, relying on gold nanoparticles (Au), modified glassy carbon (GC) electrode coated with nitro-energetic memory-poly(carbazole-aniline) copolymer (Cz- co-ANI) film (e.g., TNT memory-GC/P(Cz- co-ANI)-Au modified electrode). Current was recorded against concentration to build the calibration curves that were found to be linear within the range of 100-1000 μg L for 2,4,6-trinitrotoluene (TNT) and 2,4-dinitrotoluene (DNT): 50-1000 μg L for 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX). The corresponding limits of detection were 25 μg L for TNT, 30 μg L for DNT, and 10 μg L for both RDX and HMX, using nitro-energetic memory-GC/P(Cz- co-ANI)-Au electrodes. These electrodes were used separately, and specific determinations were made in various mixtures of nitro-energetic materials. The developed method could be efficiently used in electroanalyzing nitroaromatics and nitramines in military explosives (i.e., comp B, octol, and comp A5). The sensor electrodes were specific for the tested nitro-energetic compounds and did not respond to paracetamol-caffeine-based analgesic drug, acetylsalicylic acid (aspirin), sweetener, and sugar that can be used as camouflage materials in passenger belongings. The developed method was statistically validated against the standard LC-MS reference method in contaminated clay soil samples containing TNT and RDX explosives.

Fe‐enriched Clay‐coated and Reduced Graphene Oxide‐modified N‐doped Polymer Nanocomposite: A Natural Recognition Element‐based Sensing Electrode for DNT

“…In support of such a test, Saglam et al. also selectively detected DNT and other nitro‐compounds in contaminated clay soil by electrochemical method using Au NP and poly (carbazole‐aniline) impregnated GCE . They validated the electro‐chemical measurements with the conventional LC‐MS measurements and recommended future use of electrochemical methods for the detection of nitro‐compounds.…”

Recent Advances in Electrochemical Sensors Based on Molecularly Imprinted Polymers and Nanomaterials

“…Thus, the electropolymerization could be an alternative method with very attractive features to overcome the difficulties of producing MIPs for macromolecules such as proteins . The electrosynthesis of MIPs involves the use of various kinds of electroactive monomers as previously reported in literature such as pyrrole , aniline , thiophene , 3,4 ethylenedioxythiophene , dopamine .…”

Selective Electrochemical Determination of Dopamine with Molecularly Imprinted Poly(Carbazole‐co‐Aniline) Electrode Decorated with Gold Nanoparticles

“…Additionally, the working electrode can be modified with different polymeric materials and nanoparticles . Nanoparticles have advantages such as improved surface activity, excellent electrical/optical properties and high specific surface area .…”