The electro-oxidation of epinephrine (EPI), acetaminophen (ACT) and Mefenamic acid (MEF) has been investigated by application of nickel hydroxide nanoparticles / multi-walled carbon nanotubes modified glassy carbon electrode (MWCNT-NHNPs/GCE) using cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry (CA) methods. The modified electrode showed suitable electrochemical responses for EPI, ACT and MEF determination. Under the optimum conditions the electrode provides a linear response versus EPI, ACT and MEF concentrations in the range of 0.5-180 μM, 0.1-180 μM, and 0.1-85 respectively using the DPV method. Application of CA method showed linear responses for EPI and ACT concentrations in the range of 1-600 μM and 1-500 μM respectively. The CA results for MEF showed two linear range of 1-50 μM and 60-600 μM. The modified electrode was used for determination of EPI, ACT and MEF in human serum and urine with satisfactory results.
