C.I. Direct Violet 66 is a multifunctional dye. Dyes are essential tools in biological experiments, aiding researchers in observing and analyzing cell structures, tracking biomolecules, evaluating cell functions, distinguishing cell types, detecting biomolecules, studying tissue pathology, and monitoring microorganisms. Their applications span basic scientific research to clinical diagnostics. Dyes are also widely used in traditional fields such as textile dyeing, as well as emerging fields like functional textile processing, food pigments, and dye-sensitized solar cells.