NiO nanoparticle/1-hexyl-3-methylimidazolium hexafluorophosphate composite for amplification of epinephrine electrochemical sensor

In this research study, NiO nanoparticle (NiO-NPs) was synthesis using a simple strategy method (chemical precipitation), then it was utilized for amplification of paste electrode (PE) at the presence of paraffin oil and 1-hexyl-3-methylimidazolium hexafluorophosphate (HPF6). NiO nanoparticle was characterized using the transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS) method. The NiO-NPs/HPF6/PE was used as electrochemical sensor for determination of epinephrine in pharmaceutical and urine samples. The sensor improved the oxidation signal of epinephrine about 2.87 times. The pH investigation confirmed that the electro-oxidation of epinephrine was relative to pH changing in the presence two electrons and two protons. The square wave voltammetric investigation showed that the oxidation current of epinephrine has linear relation with its concentration in the range 1.0 nM-300 µM with detection limit 0.5 nM.