“…These probes primarily follow two types of approaches for sensing Hg 2+ : (i) simple reversible chemosensors, which involve achieving equilibrium between the spirolactam form (nonfluorescent) and the ringopened amide form (fluorescent) due to Hg 2+ coordination [31][32][33], and (ii) chemodosimeters, which are based on irreversible mercury-promoted desulfurization reactions, including hydrolysis, cyclization and elimination reactions, due to the strong thiophilic character of Hg 2+ ions [34][35][36][37][38]. To date, various researchers have developed chemosensors (type i) that contain Page 6 of 43 A c c e p t e d M a n u s c r i p t 6 urea [39], naphthalimide [40], terphenyl [41], coumarin [42] and calix [4]arene [33] as binding functionalities due to their nucleophilic properties. However, many of these sensors are pH sensitive, which might result in poor affinity for Hg 2+ under physiological conditions.…”