Used in bioconjugation for labeling and detecting biomolecules due to its reactive maleimide group that selectively binds to thiol groups in cysteine residues. Commonly applied in fluorescence imaging and flow cytometry because of its bright fluorescence and photostability. Ideal for tracking protein interactions, cellular uptake, and localization in live and fixed cells. Also utilized in developing diagnostic assays and fluorescent probes where high sensitivity and specificity are required.