A simple colorimetric method using gold nanoparticles for the detection of 2-mercaptobenzothiazole in aqueous solutions, soil and rubber

In this study, ultraviolet–visible (UV–Vis) spectrophotometry approach was developed to measure the trace amounts of 2-mercaptobenzothiazole (2-MBT) in aqueous solutions, soil, and rubber using surface plasmon resonance (SPR) property of gold nanoparticles (AuNPs). The presence of 2-MBT leads to aggregation of AuNPs with red-to-blue colour shifts. The experimental parameters such as pH, buffer, the concentration of AuNPs solution, surfactant, contact time, amount of 2-MBT, electrolyte were optimised. This method showed good linearity for the determination of 2-MBT in the range of 10–100 μg L−1 with the coefficient of determination (R2) of 0.999. The limit of detection (LOD) was 2 μg L−1. Relative standard deviation (RSD) was obtained 1.5% and 3%. The measurement of 2-MBT was successfully performed in the water of the Karun river, drinking water of Ahvaz city, wastewater of the Karun river, the soil of Ramin Power Plant, and rubber. Simple, low-cost, accurate, and without need separation steps is the superiorities of the proposed spectrophotometry method compared to the other methods.