A graphitic carbon nitride (g-C3N4/Fe3O4) nanocomposite: an efficient electrode material for the electrochemical determination of tramadol in human biological fluids
In the present study, a graphitic carbon nitride/Fe3O4 (g-C3N4/Fe3O4) nanocomposite/carbon paste electrode was used as a highly sensitive sensor for the voltammetric determination of tramadol (Tr) in an aqueous solution. The g-C3N4/Fe3O4 nanocomposite was synthesized by simple calcination of g-C3N4 and ferrite (Fe3O4) magnetic nanoparticles, which was then utilized to fabricate a modified carbon paste electrode (g-C3N4/Fe3O4-CPE). The nanocomposite was thoroughly characterized by various techniques including field emission scanning electron microscopy, energy dispersive X-ray analysis, X-ray diffraction and Fourier transform infrared spectroscopy. The effects of some parameters, such as the solution pH, scan rate, accumulation time and potential, interferents and concentration of Tr, were studied to optimize the experimental conditions; under the optimized conditions, the proposed electrode showed significant detection efficiency for Tr determined using differential pulse voltammetry over the concentration ranges of 0.2–14.0 μM and 14.0–120.0 μM and a detection limit of 0.1 μM. The proposed sensor was successfully applied for the determination of Tr in various real samples without any complex sample pretreatment.