Used in photodynamic therapy as a photosensitizer due to its ability to generate reactive oxygen species under light exposure. Its carboxylic acid groups enhance water solubility and allow for easy conjugation to nanoparticles or biomolecules, making it suitable for targeted cancer treatment. Also applied in dye-sensitized solar cells and as a catalyst in organic reactions. Its strong absorption in the visible light range improves efficiency in light-driven applications.