Tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) dichloride ([Ru(dpp)3]2+) is an electrochemiluminescent (ECL) probe and oxygen-sensitive sensor. Tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) dichloride can be used to modify electrode surfaces for the detection of sulfates (S2O82-) and oxalates, based on electrochemical reactions that generate excited-state species, releasing photons through irreversible redox reactions. Tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) dichloride utilizes the oxygen quenching of fluorescence mechanism, where fluorescence intensity reflects the metabolic rate of living microorganisms or oxygen levels within cells/tumors, allowing for real-time detection. Tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) dichloride's main applications include microbial detection, antibacterial activity studies, and tumor microenvironment research.