Designing and characterization of a novel sensing platform based on Pt doped NiO/MWCNTs nanocomposite for enhanced electrochemical determination of epinephrine and tramadol simultaneously

In the present study, we have designed a novel sensing platform based on Pt doped NiO nanoparticles and multi-walled carbon nanotubes (MWCNTs) modified glassy carbon electrode (Pt-NiO/MWCNTs/GCE) to determine epinephrine (EP) and tramadol (TR) simultaneously. To synthesize Pt doped NiO nanoparticles, a simple sol-gel procedure was applied. The structures of the synthesized Pt doped NiO nanoparticles and Pt doped NiO/MWCNTs nanocomposite were characterized using field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX) techniques. According to electrochemical studies, the fabricated sensor could accelerate electron transfer reactions of EP and TR and boost their oxidation signal. Under the optimal conditions, the Pt-NiO/MWCNTs/GCE displayed wide linear dynamic ranges of 0.5-300 mu M and 1.0-240 mu M with low detection limits of 0.035 mu M and 0.084 mu M towards EP and TR, respectively. The proposed sensor has several advantages including high effective surface area, comfortable preparation, excellent sensitivity, stability and satisfiable reproducibility towards EP and TR determination. The results suggested that the Pt-NiO/MWCNTs/GCE is a hopeful sensor to determine EP and TR in biological and pharmaceutical samples with a significant recovery.