Electrochemical determination of acetaminophen in the presence of propranolol using an electrode modified with a Schiff base from 2-hydroxy-1-naphthaldehyde and ethylenediamine and multi-walled carbon nanotubes

A carbon paste electrode, modified with N,N′- bis -(2-hydroxy-1-naphthalidene)ethylenediamine and multi-walled carbon nanotubes ( HNED-MWCNPE ), was used for the determination of acetaminophen ( ACOP ) and propranolol ( PP ). Cyclic voltammetry ( CV ), chronocoulometry, chronoamperometry and differential pulse voltammetry ( DPV ) techniques were employed to study electro-oxidation of ACOP. The results revealed that the modified electrode showed an electrocatalytic activity toward the anodic oxidation of acetaminophen by a marked enhancement in the current response in buffered solution at pH 8.0. Some kinetic parameters such as the electron transfer coefficient (α) were also determined for the ACOP oxidation. The linear concentration range of 1 × 10 −3 −1 × 10 −6 M with a detection limit of 4.6 × 10 −8 M ( n = 16) for ACOP was obtained using DPV (pH 8.0). The modified electrode shows good sensitivity, selectivity and stability. The prepared electrode was also applied for the determination of ACOP in human blood serum.