Substitution group effects of 2-mercaptobenzothiazole on gold nanoparticles toward electrochemical oxidation and sensing of tetrabromobisphenol A

The electrochemical behaviors of tetrabromobisphenol A (TBBPA) on the surface of electrochemically deposited gold nanoparticles (AuNPs) in the presence of 2-mercapto-benzothiazole (MBT) and MBT with different groups on C-6 position were studied. It was found that the substitution groups on C-6 position of MBT molecule had remarkable influences on the oxidation activity of TBBPA. Double potential-step chronocoulometry experiments indicated that the substitution groups exhibited obvious influences on the accumulation ability of TBBPA on AuNPs surface. Based on the substitution group-related signal amplification strategy, a highly sensitive electrochemical sensing platform was developed for TBBPA. The linear range was from 20.0 ng L⁻¹ to 40.0 μg L⁻¹, and the detection limit was 7.2 ng L⁻¹ (i.e. 13.2 pM). This new sensing system was used in e-waste and waste water samples, and the results consisted with the values that obtained by high-performance liquid chromatography.