Cy3.5 azide is a solid material dye ready for the use in Click Chemistry reaction. Most derivatives of non-sulfonated cyanines have low aqueous solubility except for hydrochlorides of hydrazides and amines. For biomolecule labeling, 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.
Cy3.5 azide could easily interfere with a radical polymerisation process as it contains a variety of double bonds. The Cy-3 modified initiator was then used to grow the modified PMPC-PDPA directly from the dye [1].
Reference:
[1] Gaitzsch, J. ; Delahaye, M.; Poma, A.; Du Prez, F.; Battaglia, G. Comparison of metal free polymer-dye conjugation strategies in protic solvents. Polymer Chemistry, 2016, 7(17), 3046–3055.