The application of nanomaterials in various fields of science and technology has been extensively developed due to the unique properties of these materials [1–3]. Many electrodes have been modified by Ni, NiO2, Ni(OH)2 particles and nanoparticles on traditional electrode surfaces. In contrast to Ni nanomaterials which are unstable and easily oxidized in air and solution, hydroxide (or oxide) of these materials are relatively stable. Dopamine (DA) is an important neurotransmitter of the catecholamine group and is well characterized by its electrochemical activity [4]. Piroxicam (PRX) is a nonsteroidal anti inflammatory drug (NSAID) that also possesses analgesic and antipyretic properties. This drug has been widely used in the treatment of rheumatoid arthritis and other inflammatory disorders [5]. It has been found that PRX produced dual effects on dopamine-related behaviors in rats [6]. Therefore it would be useful to study simultaneous determination of DA and PRX . In this work the synthesized nickel hydroxide nanoparticles (NHNPs) / multi walled CNTs (MWCNTs) composite film-modified glassy carbon (GC) electrode was fabricated as a new modified electrode. The electro-oxidation of dopamine (DA) and piroxicam (PRX) has been investigated by application of the modified electrode using cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry (CA) methods. The modified electrode showed excellent electrochemical responses for DA and PRX determinations. Under the optimum conditions the electrode provides a linear response versus DA and PRX concentrations in the range of 1.0to100.0 M and 1.0to 110.0 M and with a detection limit of 0.72 and 0.53 M respectively, using the DPV method. The interfering study of some species showed no significant interference with determination of DA and PRX could be observed at the modified electrode. The modified electrode was used for determination of DA and PRX in human urine and blood serium with satisfactory resul
