Used as a near-infrared (NIR) fluorescent dye in biological imaging and sensing applications. Its strong absorption and emission in the NIR region make it suitable for deep tissue imaging with minimal autofluorescence and light scattering. Commonly employed in in vivo imaging, cell labeling, and as a photosensitizer in photodynamic therapy research. Also utilized in optical sensors and imaging agents due to its stability and high quantum yield in non-aqueous environments.