Electrochemical determination of cyanuric acid using the signal suppression of melamine on an overoxidized Poly-(para-aminophenol) coated glassy carbon electrode

Cyanuric acid (CA) is known as an important environmental and human toxin with low electroactivity. Therefore, it is an attractive issue to develop an electrochemical sensor for CA determination. Here, we reported a novel electrochemical sensor for the indirect electrochemical determination of CA using the complex formation between CA and melamine (MEL), for the first time. Firstly, the electrochemical conversation of MEL to electroactive polymelamine was conducted using a glassy carbon electrode modified with overoxidized Poly-(para-aminophenol) film. MEL was chosen as a probe for indirect determination, and its current intensity was recorded. CA was then added to the medium, and the decline in the current intensity was considered as the sensor response. The calibration curve within the range of 100-2500 mu mol L-1 was constructed from sensor response against CA concentration using square wave voltammetry. The limit of detection was found to be 80.28 mu mol L-1. Moreover, the proposed mechanism for the indirect determination of CA was investigated based on the quantum theory of atoms in molecules analysis. Finally, the developed method was able to exhibit an excellent recovery range (91.2-101.0%) for the real sample analysis. [GRAPHICS] .

Automated summary

We reported a novel electrochemical sensor for the indirect determination of cyanuric acid (CA) using the complex formation between CA and melamine (MEL) for the first time. The sensor utilized the electrochemical conversion of MEL to electroactive polymelamine, with the decline in current intensity upon the addition of CA serving as the sensor response. A calibration curve was constructed using square wave voltammetry, with a limit of detection of 80.28 mu mol L-1. The proposed method showed excellent recovery range (91.2-101.0%) for real sample analysis.