Used as a near-infrared fluorescent probe in biological imaging due to its strong absorption and emission in the NIR range. Enables deep tissue visualization with minimal background autofluorescence. Commonly conjugated to targeting molecules for in vivo tumor detection and real-time monitoring of cellular processes. Exhibits good photostability and water solubility, making it suitable for long-term live-cell imaging. Also applied in immunoassays and molecular diagnostics where high sensitivity and low interference are required.