Cy7 azide is a labeling reagent that ready for the use in Click Chemistry labeling. This labeling dye is a near-infrared dye which has low aqueous solubility. For biomolecule labeling, the labeling reagent has low aqueous solubility, using of organic co-solvent to dissolve this molecules 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. This product can be used for the incorporation of Cy7 azide into various biomolecules and post-synthetic modification of oligonucleotides is also available.