Abstract:
NiCo2O4/Nano-ZSM-5 nanocomposite materials were prepared by the calcination of a physical mixture of
NiCo2O4 and Nano-ZSM-5. The materials were characterized by the complementary combination of X-ray
diffraction, N2-adsorption and electron microscopic techniques. An electrochemical sensor based on
NiCo2O4/Nano-ZSM-5 nanocomposite was constructed for the simultaneous determination of ascorbic
acid, dopamine, uric acid, and tryptophan. Among the materials investigated in this study, the NiCo2O4
(30%)/Nano-ZSM-5 modified glassy carbon electrode exhibited the highest electrocatalytic activity with
excellent stability, sensitivity, and selectivity. Under the optimum conditions, wide linear ranges were
obtained from 1–1200 mM for ascorbic acid, 0.6–900 mM for dopamine, 0.9–1000 mM for uric acid, and
0.9–1000 mM for tryptophan. The detection limits were found to be 0.8, 0.5, 0.7 and 0.7 mM for ascorbic
acid, dopamine, uric acid, and tryptophan, respectively. The analytical performance of the developed sensor
was demonstrated in the determination of ascorbic acid and dopamine in commercial pharmaceutical
preparations (vitamin C tablets and dopamine injections) and uric acid in human urine samples.
