Cy5.5 hydrazide (non-sulfonated)

Cy5.5 hydrazide is a reactive dye for the labeling of biomolecules containing carbonyl groups, such as ketone and aldehydes. This dye pocesses a hydrazide group that can be used to label glycans at their reducing end or other reducing sugars, forming a hydrazone linkage. Hydrazide-containing Cyanine Dyes can react with glycoproteins and other glycoconjugates specifically via their carbohydrate groups without interfering binding site or active centers. Glycoproteins also can be labeled after periodate oxidation to form aldehyde groups. Therefore, this dye is especially applicable for the labeling of antibody. Moreover, Cy5.5 is a near infrared fluorophore with prominent ability of tissue penetration, so it is suitable for the applications which require low fluorescence background, and for the in vivo NIR imaging. For biomolecule labeling, the labeling regent has low aqueous solubility, using of organic co-solvent to dissolve this molecular is necessary for efficient reaction. First, Cyanine dye should be dissolved in organic solvent and then added to a solution of biomolecule in appropriate aqueous buffer.