Session: Advances in Electrochemistry:

TATP (triacetone triperoxide, or 3,3,6,6,9,9-hexamethyl-1,2,4,5,7,8-hexaoxanonane) is a peroxide explosive that has been exploited in terrorism activities rather than military use in the last few decades due to its thermodynamic instability, easy preparation from simple and cheap raw materials, and enormous explosive power. TATP has neither nitro groups nor aromatic functionalities, making it difficult to analyze with conventional analytical methods compared to other high explosives 2,4,6-trinitrotoluene (TNT) (nitroaromatic type explosive) or cyclotrimethylenetrinitramine (RDX) (nitramine type explosive). Different analytical techniques have been reported for the determination of TATP such as spectroscopy, fluorometry, liquid or gas chromatography (LC or GC) coupled to mass spectrometry (LC/MS and GC/MS), and thin-layer chromatography (TLC). On the other hand, these techniques are expensive, time-consuming, and solvent wasting. Additionally, spectroscopic and fluorometric techniques are not directly applicable to TATP determination. As an alternative to these methods, electrochemical methods are preferable because of their high selectivity and sensitivity, low cost, easy operation, fast response, and portability.
In this work, the surface of the glassy carbon (GC) electrode was coated with polycarbazole (PCz) conductive polymer using electropolymerization by cyclic voltammetry, performed within the potential range 0.0 – 1.6 V with a 20 mV s^-1 scan rate for 5 cycles. After the preparation of the working electrode, differential pulse voltammetry (DPV) was performed within the 10-100 mg L^-1 concentration range for TATP using the GC/PCz electrode. Reduction potential of TATP was found at - 0.95 V, and the calibration of TATP gave a linear dependence of current intensity versus concentration; I _{-0,95 V} = 5.48×10⁻² C_TATP + 14.16 (r = 0.995) where I _{-0,95 V} was the peak current intensity (µA) at -0.95 V potential and C_TATPwas the TATP concn. (mg L^-1). The limit of detection (LOD) for TATP was 3 mg L^-1. The direct electrochemical determination of TATP was successfully applied in the presence of nitroaromatic and nitramine explosives using the proposed DPV method and GC/PCz working electrode. The distinctive characteristics of the method are its capability for intact TATP determination (without acid hydrolysis) and hydrogen-bonding preconcentration of analyte on the electrode surface.

Aysem Arda

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