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Receptor-Based Detection of 2,4-Dinitrotoluene Using Modified Three-Dimensionally Ordered Macroporous Carbon Electrodes
journal contribution
posted on 2012-09-26, 00:00 authored by Melissa
A. Fierke, Eric J. Olson, Philippe Bühlmann, Andreas SteinDetection of explosives, such as 2,4,6-trinitrotoluene
(TNT), is
becoming increasingly important. Here, 2,4-dinitrotoluene (DNT, a
common analogue of TNT) is detected electrochemically. A receptor
based electrode for the detection of DNT was prepared by modifying
the surface of the walls of three-dimensionally ordered macroporous
(3DOM) carbon. Nitrophenyl groups were first attached by the electrochemical
reduction of 4-nitrobenzenediazonium ions, followed by potentiostatic
reduction to aminophenyl groups. Chemical functionalization reactions
were then performed to synthesize the receptor, which contains two
urea groups, and a terminal primary amine. Detection of DNT using
cyclic voltammetry was impeded by a large background current that
resulted from the capacitance of 3DOM carbon. Detection by square
wave voltammetry eliminated the background current and improved the
detection limit. Unfunctionalized 3DOM carbon electrodes showed no
response to DNT, whereas the receptor-modified electrodes responded
to DNT with a detection limit of 10 μM. Detection of DNT was
possible even in the presence of interferents such as nitrobenzene.