Electropolymerization of ferulic acid on multi-walled carbon nanotubes modified glassy carbon electrode as a versatile platform for NADH, dopamine and epinephrine separate detection

The polymerization of ferulic acid (poly-FA) on multi-walled carbon nanotubes (MWCNT) modified glassy carbon electrode was performed and the modified platform applied for the determination of NADH, epinephrine (EP) and dopamine (DA), one at a time. Cyclic voltammetry and chronoamperometry were employed to investigate the electrocatalytic oxidation of NADH, EP and DA on the modified electrode, in aqueous solutions. The obtained analytical curves for NADH, EP, and DA showed linear ranges between 59-1560, 73-1406, and 5-120 μmol L− 1, respectively. The detection limits were 17.7, 22.2 and 2.2 μmol L− 1 for NADH, EP and DA, respectively. The catalytic constant for the oxidation of NADH, EP and DA on the modified electrode were 5.56 × 103, 6.99 × 103 and 1.15 × 104 L mol− 1 s− 1, respectively. The obtained versatile electrode was applied to the successful determination of EP, in epinephrine hydrochloride injection and DA in pharmaceutical samples.