Highly sensitive determination of nitrite using a carbon ionic liquid electrode modified with Fe3O4 magnetic nanoparticle

A carbon ionic liquid electrode modified with Fe3O4 magnetic nanoparticle (Fe3O4NPs/CILE) was employed for nitrite determination by cyclic voltammetry. The results showed that the Fe3O4NPs/CILE exhibited a significant improvement in the oxidation peak current of nitrite. After optimizing the operational conditions, a linear response range from 10 to 900 µmol L−1 with a low detection limit of 0.70 µmol L−1 was obtained. The proposed sensor was stable with a sensitivity of 0.0402 μA μmol−1 L and good repeatability evaluated in terms of relative standard deviation (RSD < 2.1 % for n = 6). Possible interferences from several coexisting ions were evaluated. The sensor was applied for voltammetric determination of nitrite in some real samples. The results were consistent with those obtained with the standard spectrophotometric procedure.