Integrating photoinduced gold nanoparticle formation inhibition and salt-assisted microextraction for colorimetric sensing of 2-mercaptobenzothiazole

The detection of 2-mercaptobenzothiazole (MBT), a widely used industrial compound posing significant environmental and health risks, demands efficient and practical solutions. Here, we present a novel colorimetric sensor integrating photoinduced gold nanoparticles (AuNPs) formation inhibition with salt-assisted liquid–liquid microextraction (SALLME) for rapid and sensitive MBT detection. This approach eliminates the need for AuNP seeds, enabling simple and cost-effective analysis at room temperature. The sensor demonstrated a wide linear range (5–640 μM, R 2  = 0.990) and an impressive limit of detection (LOD) of 0.024 μM, outperforming several conventional methods. Spiked recovery tests using river water and soil samples yielded recovery rates of 94.0–107.5 % with relative standard deviations below 7.1 %, confirming its analytical accuracy and robustness in complex matrices. This study offers a promising pathway for developing practical MBT detection techniques with broad environmental applicability.