A highly sensitive electrochemical method for the determination of Sudan I at polyvinylpyrrolidone modified acetylene black paste electrode based on enhancement effect of sodium dodecyl sulphate

Abstract

A novel electrochemical method for the sensitive determination of trace Sudan I at a polyvinylpyrrolidone (PVP) modified acetylene black carbon paste electrode (PVP/CPE) based on the enhancement effect of sodium dodecyl sulphate (SDS) was reported. Compared with the poor response at a bare acetylene black paste electrode (CPE), a well-defined oxidation peak of Sudan I was observed at the PVP modified CPE. The oxidation peak current of Sudan I was further enhanced with the addition of SDS, which was attributed to the enhancement effect of SDS at PVP/CPE. Under optimal working conditions, the oxidation peak current of Sudan I was proportional to its concentration in the range of 2.0 × 10⁻⁷–8.0 × 10⁻⁶ mol L⁻¹, with a low detection limit of 1.0 × 10⁻⁸ mol L⁻¹. The proposed method was successfully applied to the detection of Sudan I in chilli products.

Keywords:

• Sudan I
• polyvinylpyrrolidone
• sodium dodecyl sulphate
• acetylene black paste electrode
• enhancement effect

Acknowledgement

The authors acknowledge financial support by the National Nature Science Foundation of China (Nos. 60571042, 30770549, 20805035 and 90817103).