Used as a photosensitizer in photodynamic therapy for cancer treatment, Purpurin 18 effectively generates reactive oxygen species when exposed to light, enabling targeted destruction of tumor cells. It is also employed in dye-sensitized solar cells due to its strong absorption in the near-infrared region, enhancing light-harvesting efficiency. Additionally, it serves as a fluorescent probe in biological imaging, allowing visualization of cellular structures with high contrast. Its natural origin and biodegradability make it suitable for eco-friendly dye applications in textiles and coatings.