ICG Dichlorotriazine is a hydroxyl reactive near infrared (NIR) fluorescent dye and used to generate a stable fluorescence signal in bioimaging. NIR fluorescence allows to observe the deep image from the surface of skin and being utilized in a wide range of research fields. The maxima of Ex/Em values are at 785/811 nm. ICG might be excited using 750-800 nm laser line or LED and displays excellent optical property. Dichlorotriazines are among the few reactive groups that are reported to react directly with polysaccharides and other alcohols in aqueous solution, provided that the pH is >9 and other nucleophiles are not present. Hydroxyls irreversibly displace one of chlorines at triazine ring to yield an aryl ether linkage. We offer ICG dichlorotriazine for labeling of polysaccharides and alcohols on biomolecules for cellular labeling and detection.