High-sensitivity detection of hydrogen sulfide and water content using a Triphenylamine-based fluorescent probe: Applications in food safety monitoring

This study reports the design and synthesis of a fluorescent probe TPA-ACL based on the triphenylamine (TPA) structure for the dual detection of hydrogen sulfide (H₂S) and water content. In the presence of H₂S, TPA-ACL exhibits a pronounced “turn-on” fluorescence response, demonstrating excellent selectivity and high sensitivity with a detection limit (LOD) of 2.02 nM. Furthermore, TPA-ACL enables real-time detection of H₂S using test strips, allowing for visual monitoring of H₂S gas generated during food spoilage, indicated by a color change from pale yellow to deep yellow. The probe was also successfully applied for the quantitative analysis of trace water content in food samples, with a detection limit (LOD) of 70.7 ppm (0.0071 vol%) in tetrahydrofuran (THF). This study provides a sensitive, efficient, and practical tool for detecting H 2 S and water content, demonstrating significant potential for applications in food safety monitoring.