Electrochemical sensor based on molybdenum oxide nanoparticles for detection of dopamine

Water nanocolloids of molybdenum oxide were synthesized by using a laser writing of a solid molybdenum target by a focused picosecond pulsed laser beam. The molybdenum oxide nanoparticles are then used to fabricate modified screen-printed carbon paste electrode. Morphology and compositional-structural properties of the samples were investigated by Scanning Transmission Electron Microscopy and X-ray diffraction spectroscopy. The sensors tested show enhanced electro-catalytic behavior for dopamine detection (also in presence of KCl, NaCl, glucose, uric acid, ascorbic acid and folic acid), in phosphate buffered saline (pH= 7). Under the optimal conditions, the peak current of dopamine increases linearly with the concentration in the 10–500 μM range, with the lowest detection limit of 43 nM. All these data indicate an excellent selectivity of this type of sensor towards main interferents, made it as a potential candidate for the detection of dopamine in pharmaceutical and clinical preparations.