Determination of nitrite with the electrocatalytic property to the oxidation of nitrite on thionine modified aligned carbon nanotubes

A thionine modified aligned carbon nanotubes (ACNTs) electrode was fabricated and was used to electrochemically determine nitrite. The thionine modified ACNTs electrode exhibited enhanced electrocatalytic behavior to the oxidation of nitrite. The electrochemical mechanism of the thionine/ACNTs electrode towards the oxidation of nitrite was discussed. The thionine modified ACNTs electrode exhibited fast response towards nitrite with a detection limit of 1.12 × 10−6 mol L−1 and a linear range of 3 × 10−6 – 5 × 10−4 mol L−1. The proposed method was successfully applied in the detection of nitrite in real samples. Keywords: Thionine, Aligned carbon nanotubes, Nitrite, Modified electrode, Electrocatalytic oxidation