Reaction-based fluorescent probes for SO2 derivatives and their biological applications

As a well-known toxic air pollutant, SO2 and its derivatives can cause great harm to the human body, including respiratory responses, allergic reactions, cancer, neurological disorders and cardiovascular diseases. On the other hand, SO2 can be endogenously generated in mammals and serves as a gaseous signaling molecule. Evidences show that SO2 and its derivatives play crucial roles in modulating a wide range of physiological processes, including vasodilatation, antihypertension, regulation of cardiovascular function and intracellular redox status. The molecular mechanisms dictating the biological formation of SO2 and its role in many biological processes remain largely unclear. Reaction-based fluorescent probes offer powerful means to monitor the physiological actions of SO2 derivatives in their native environments with minimal perturbation to the living systems. This review shows up-to-date research trends on reaction-based fluorescent probes for SO2 derivatives. The design principles and chemical structures of the probes and their biological applications are highlighted.