In this study we report synthesis and application of NiO nanoparticle (NiO/NPs) carbon paste electrode (NiO/NPs/CPE) as high sensitive sensors for voltammetric determination of Nalbuphine (NB). The NiO/NPs was characterized with different methods such as SEM and XRD. The cyclic voltammogram showed an irreversible oxidation peak at 0.57 V (vs. Ag/AgClsat), which corresponded to the oxidation of NB. Compared to common carbon paste electrode, the electrochemical response was greatly improved. The electro-oxidation of NB occurred in a pH-dependent 1e− and 1H+ process, and the electrode reaction followed a diffusion-controlled pathway. Under the optimum conditions, the voltammetric oxidation peak current of NB showed linear dynamic ranges with a detection limit of 0.5 μM for NB. The novel sensor has been found selective and successfully implemented for the determination of NB in water, serum and urine samples.
