A portable and efficient chemical dosimeter for rapid visual analysis of 3-Monochloropropane-1,2-diol (3-MCPD) in food samples

3-Chloro-1,2-propanediol (3-MCPD) is a common contaminant in food and has been classified as a Group 2B carcinogen. Given growing food safety concerns, rapid and effective analytical methods are urgently needed. This study designed a new chemical dosimeter based on a benzothiazole derivative (BT-NH2) for high-sensitivity, rapid 3-MCPD analytical in food. The chemical dosimeter quantitatively analyzes 3-MCPD via nucleophilic substitution of its chlorine atom by BT-NH2's amino group, causing fluorescence quenching. Experimental results showed BT-NH2 exhibited a fast response (completed within 4 s), excellent linearity, good specificity, and a low detection limit of 0.048 mg/L for 3-MCPD. Furthermore, a test strip immobilized with BT-NH2 was developed for the visual analysis of 3-MCPD, showing outstanding performance. This study proposed an innovative 3-MCPD analytical method with the characteristics of high sensitivity, selectivity, ultrafast response, simple operation, and on-site visual observation, which addresses the urgent need for food safety monitoring.