Lyso-Tracker Green is a fluorescent small-molecule probe designed specifically for labeling lysosomes in living cells As a weakly basic fluorophore it accumulates selectively in acidic cellular compartments primarily lysosomes due to protonation under low pH conditions Unlike conventional dyes such as acridine orange or neutral red Lyso-Tracker Green exhibits superior organellar selectivity and requires only nanomolar concentrations to produce robust fluorescent labeling It is widely utilized in biomedical research for imaging lysosomal localization and analyzing cellular physiology in live-cell assays but is not compatible with fixed-cell staining protocols