Used as a fluorescent probe in biological imaging due to its strong near-infrared (NIR) emission. It readily penetrates cell membranes and localizes in mitochondria, making it ideal for tracking mitochondrial activity and membrane potential in live cells. Its photostability allows for long-term imaging with minimal signal loss. Also employed in photodynamic therapy research for targeted cell illumination and detection in deep tissues owing to its NIR absorption. Commonly conjugated to biomolecules for targeted detection in immunoassays and molecular sensing.