Fabrication of a carbon paste electrode modified with multi-walled carbon nanotube with some polyaromatic hydrocarbons for stripping voltammetric determination of TNT explosive in the environmental samples

In this study, a new modified carbon paste electrode (CPE) based on multi-walled carbon nanotubes andfluoranthene (a polyaromatic hydrocarbon) is described. To fabricate new kind of modified carbon pasteelectrode sensitive to 2,4,6-trinitrotoluene (TNT), the interaction between some polyaromatic hydrocarbons andTNT characterized by UV-visible spectroscopy. UV-visible spectra of TNT and fluoranthene theoretically provefluoranthene is a better receptor to TNT. Electrochemical experiments indicated that fluoranthene-MWCNTsmodifiedcarbon paste electrode remarkably enhances the sensitivity of the voltammetric method and providesmeasurements of this explosive to the trace level. The effective parameters in the sensor response wereexamined. Under optimized operational conditions, a linear response range from 50–1000 ng mL-1 was obtained.The detection limit for TNT determination was 2 ng mL-1. For 7 successive determinations of 100.0 ng mL-1 ofTNT, relative standard deviation of 5.2% was obtained. The procedure was applied for the determination of TNTin water spiked samples; recoveries were higher than 94% in all cases.

Keywords:

Multi-wall carbon nanotubes (MWCNT) , Environmental monitoring , 2 , 4 , 6-Trinitrotoluene (TNT) , Voltammetry , Fluoranthene