Cy5.5 Alkyne

Unit Size
Price (USD)
Cat.#: 1346-1
Unit size: 1 mg
in stock
Cat.#: 1346-5
Unit size: 5 mg
in stock
Cat.#: 1346-25
Unit size: 25 mg
in stock
Cat.#: 1346-100
Unit size: 100 mg
in stock

Cy5.5 Alkyne (also sold as sulfo-Cyanine5.5 Alkyne) is a bright and photostable near-IR dye that is spectrally similar to Alexa Fluor® 680, DyLight® 680, and IRDye® 680 dye. The Cy5.5 Alkyne is water-soluble, hydrophilic dye often a reagent of choice for assay where minimal non-specific binding and exceptional brightness is required. Cy5.5 Alkyne is pH insensitive from pH 4 to pH 10 and produces minimal autofluorescence of biological specimens in this region of the spectrum. Fluorescence of this long-wavelength Cyanine dye is not visible to the human eye but is readily detected by most imaging systems.

The NIR-fluorescent Cy5.5 Alkyne reacts with azide via a copper-catalyzed click reaction (CuAAC) to form a stable triazole linker. After the click reaction with the conjugate is still remains very bright, water-soluble, and pH-insensitive. A probe for copper-less detection (Cy5.5 DBCO) is also available for application where the presence of copper is not acceptable.

Azide, picolyl azide
Abs/Em Maxima
675/694 nm
Extinction coefficient
190,000 cm-1M-1
Water, DMSO, DMF
Spectrally similar dyes
Alexa Fluor® 680, DyLight® 680, IRDye® 680
Molecular weight
Storage conditions
Shipping conditions
Ambient temperature

Cy®Dye is a trademark of GE Healthcare.