Pharmaceutical Electrochemistry: the Electrochemical Behaviour of Paracetamol at ZnO Nanoparticales/1, 2-Napthaquinone-4-Sulphonic Acid Glassy Carbon Modified Electrode

The development of a new modified glassy carbon electrode with ZnO nanoparticales and a polymer film of 1, 2-napthaquinone-4-sulphonic acid have been reported. The electrochemical behaviour of paracetamol in pharmaceutical form at ZnONPs-Nq/GC modified electrode using cyclic and linear sweep voltammetry was investigated. The modified electrode exhibited excellent electrocatalytic activity for the behaviour of PA. The anodic and cathodic peak currents of PA at ZnONPs-Nq/GCME increased significantly when compared with that at a bare glassy carbon electrode and ZnONPs/GCE, also its potential shifted to more negative value. The effect of pH, concentration and scan rate were also investigated. The anodic peak current was linearly proportional to the concentration of PA in the range from 0.088 to 1.1 mM with detection and quantification limits of 30.03×10-6 and 10.01×10-5 M respectively. The pH 7.6 is the gives value for studying the behaviour of PA at the modified electrode. Some parameters such as the diffusion coefficient (D), the electron transfer rate constant (ks) and the electron transfer coefficient (α) were calculated and found for the PA oxidation to be 5.998×10-6 cm2 s–1, 11.279 s-1 and 0.721 respectively. The modified electrode shows high selectivity, satisfied stability and good reproducibility for the detection of PA. This modified electrode was successfully applied to PA determination in pharmaceuticals tablets samples.