Cy3 azide is a non-sulfonated dye ready for the use in Click Chemistry reaction which can be detected by various fluorometers, imagers, and microscopes. The reagent can be detected by naked eye on gels because of inherently high extinction coefficient. For biomolecule labeling, using of organic co-solvent to dissolve this molecular is necessary for efficient reaction. Product is available both as solid compound, and as 10 mM solution in DMSO. First, Cyanine dye should be dissolved in organic solvent and then added to a solution of biomolecule in appropriate aqueous buffer. Water-soluble version of this reagent is also available. Most derivatives of non-sulfonated cyanines have low aqueous solubility except for hydrochlorides of hydrazides and amines.
In protein analysis, proteins labeled by Cy3 azide couple with Cy5 azide can substantially simplifies the target identification process than only one fluorescent dye [1].
Reference:
[1]. Park, H.; Koo, J.Y.; Srikanth, Y.V.V.; Oh, S.; Lee, J.; Park, J.; Park, S.B. Nonspecific protein labeling of photoaffinity linkers correlates with their molecular shapes in living cells. Chemical Communications, 2016, 52(34), 5828–5831.