Charge–transfer interaction between melamine and quinones: Towards voltammetric determination of melamine

This communication describes a new voltammetric method for the determination of melamine based on the charge–transfer interaction between quinones and melamine. Three types of quinones, i.e., tetrachloro-p-benzoquinone (TCBQ), benzoquinone (BQ), and vitamin K1 (VK1) were employed in this study. The charge–transfer interaction activity of quinones with melamine was found to depend on the structure of quinones, of which TCBQ with four electron-withdrawing chloro groups exhibits the highest interaction activity with melamine. Such a property was further employed for the voltammetric determination of melamine based on the decrease in the redox peak currents of TCBQ/TCBQ− caused by the pre-consumption of TCBQ with melamine. Under the conditions employed in this study, the decrease in the peak current of TCBQ was linear with the concentration of melamine within a concentration range from 10 μM to 1.0 mM.

► UV–vis spectroscopic and electrochemical demonstration on the charge–transfer interaction between TCBQ and melamine
► Calculation of kinetics and thermodynamics of the interaction
► A facile and straightforward approach to voltammetric detection of melamine.