Electrochemical sensing of 2-methyl-4, 6-dinitrophenol by nanomagnetic core shell linked to carbon nanotube modified glassy carbon electrode

Electrochemical behavior and sensing of 2-methyl-4, 6-dinitrophenol as an herbicide has been investigated by cyclic voltammetry (CV) and square wave voltammetry (SWV). We have synthesized a cefazolin (CEF) immobilized nanomagnetic core-shell (Fe3O4@SiO2-(CH2)(3)-CEF) and attached it on the modified glassy carbon electrode (GCE/MWCNT) through electrostatic adsorption (GCE/MWCNT/CEF-SiO2@Fe3O4). 2-Methyl-4, 6-dinitrophenol has an oxidation peak that is related to the formation of nitrosamine from hydroxylamine species. This peak was applied for quantifying determination of 2-methyl-4, 6-dinitrophenol. The electrochemical oxidation involves two electron transfers accompanied by two protons. The electrochemical process was controlled by adsorption. The good agreement between the obtained computational studies and the experimental results has demonstrated that outer sphere electron transfer occurred on modified electrode. The new electrochemical sensor was applied to determination of 2-methyl-4, 6-dinitrophenol by SWV in the range of 1.0 x 10(-10) to 1.5 x 10(-7) M with a detection limit of 0.1 nM. The proposed sensor was applied for determination of 2-methyl-4, 6-dinitrophenol in water samples.