A multifunctional fluorescent probe for dual-color visualization of intracellular mitochondria and lipid droplets and monitoring of SO2 in vivo

•A SO2-dependent strategy was first proposed to construct multifunctional probes.•MLD-SO2 was used for dual-color visualization of intracellular mitochondria-LDs.•MLD-SO2 displayed excellent sensitivity and high selectivity to SO2.•MLD-SO2 has been successfully applied to detect SO2 in cells and zebrafish.•The detection of SO2 in bean sprouts was realized for the first time by MLD-SO2.