Gold nanoparticles-carbon nanotubes modified sensor for electrochemical determination of organophosphate pesticides

An electrochemical sensor was developed for the detection of organophosphate pesticides based on electrodeposition of gold nanoparticles on a multi-walled carbon nanotubes modified glassy carbon electrode. Cyclic voltammetry was employed in the process of electrodeposition. Field emission scanning electron microscope and X-ray diffraction techniques were used for characterization of the composite. Organophosphate pesticides (e.g. parathion) were determined using linear scan voltammetry. A highly linear response to parathion in the concentration range from 6.0 × 10−5 to 5.0 × 10−7 M was observed, with a detection limit of 1.0 × 10−7 M estimated at a signal-to-noise ratio of 3. The method has been applied to the analysis of parathion in real samples.