Lysosomal-targeted fluorescent probe for detecting SO₂ derivatives in human umbilical vein endothelial cells

A fluorescent probe (NBC), constructed by benzothiazole-coumarin and naphthalimide derivatives, was developed for the detection of SO₂ derivatives using the FRET (Förster Resonance Energy Transfer) strategy. NBC presented large Stokes shift (180 nm), fast response (2 min), high sensitivity (LOD: 45 nM) and an excellent linear relationship in response to SO₂ derivatives. Moreover, NBC has been successfully applied to detect SO₂ derivatives in food samples and living cells. NBC holds significant potential for monitoring changes in both exogenous and endogenous SO₂ derivatives in human umbilical vein endothelial cells (HUVEC cells). Additionally, it demonstrates remarkable lysosomal-targeting capabilities, allowing for the observation of dynamic alterations within lysosomes.