Sulfo-Cy3 azide is a sulfonated, hydrophilic and highly water soluble dye for Click Chemistry. For labeling of various molecules in aqueous phase for brightness and photostability of fluorophore, sulfo-Cy3 azide is an ideal choice. Click reaction can be carried out in pure water without need to use organic co-solvent. For labeling proteins and even intact biological objects, no organic co-solvent is needed. In life science, the sulfonate groups make the Cy dyes soluble in water and also reduce fluorescence-quenching which can arise from dye–dye interactions.
In vitro, sulfo-Cy3 azide was used for fluorescent microscopy staining. Human U87MG glioblastoma cells that overexpress uPAR were just stained by Cy3-AE105 conjugate [1].
Reference:
[1] Sun, L. Gai, Y. Anderson, C.J.; Zeng, D. Highly-efficient and versatile fluorous-tagged Cu (I)-catalyzed azide–alkyne cycloaddition ligand for preparing bioconjugates. Chemical Communications, 2015, 51, 17072–17075.