Used as a near-infrared fluorescent probe in biological imaging due to its strong absorption and emission in the NIR region. Ideal for detecting cellular structures and monitoring biological processes in real time, especially in deep tissue imaging where longer wavelengths reduce background autofluorescence and light scattering. Its carboxyl groups allow for easy conjugation to biomolecules such as antibodies, peptides, or proteins, enabling targeted labeling in immunoassays and molecular sensing. Also applied in photodynamic therapy research and as a sensor in fluorescence-based detection systems for metal ions or pH changes in living cells.