Chitosan-PEG-Cy3 is a fluorescent labeling reagent that combines the Cy3 fluorescent dye with Chitosan and polyethylene glycol (PEG). Cy3 fluorophores are frequently utilized in applications like immunolabeling, nucleic acid labeling, fluorescence microscopy, and flow cytometry. The maximum emission wavelength of Cy3 is approximately 562-570 nm. Chitosan exhibits antimicrobial activity against various bacteria and fungi.