1H-Benz[e]indolium, 2-[5-[3-[6-[(3-azidopropyl)amino]-6-oxohexyl]-1,3-dihydro-1,1-dimethyl-2H-benz[e]indol-2-ylidene]-1,3-pentadien-1-yl]-1,1,3-trimethyl-, chloride (1:1)

Cy5.5 azide is a functionalized cyanine dye containing an azide group which can react with alkynes for copper-catalyzed Click Chemistry. Cyanine5.5 is a far-red dye working great for live organism imaging and applications requiring low fluorescence background.

Appearance: Dark blue solid
ex/em: 680/698 nm (PBS buffer)
Extinction coefficient (ε): 198000 Lmol1cm1
Quantum yield (Φ): 0.20

Cyanine 5.5 azide (CY 5.5 azide) is a potent fluorescent dye. Cyanine 5.5 azide can label DNA. Cyanine 5.5 azide can be used for NIR live organism imaging. (λex=684 nm, λem=710 nm)[1][2]. Cyanine 5.5 azide is a click chemistry reagent, it contains an Azide group and can undergo copper-catalyzed azide-alkyne cycloaddition reaction (CuAAc) with molecules containing Alkyne groups. It can also undergo strain-promoted alkyne-azide cycloaddition (SPAAC) reactions with molecules containing DBCO or BCN groups.

[1] Sun H, et, al. Zwitterionic Cross-Linked Biodegradable Nanocapsules for Cancer Imaging. Langmuir. 2019 Feb 5;35(5):1440-1449. DOI:10.1021/acs.langmuir.8b01633
[2] Damaj MI, et, al. In vivo characterization of a novel inhibitor of CNS nicotinic receptors. Eur J Pharmacol. 2005 Oct 3;521(1-3):43-8. DOI:10.1016/j.ejphar.2005.06.056