Sulfo-Cyanine5.5 is a water-soluble, hydrophilic fluorophore which possesses emission in far red area of the spectrum, an analog of Cy5.5®. As other cyanine dyes, sulfo-Cyanine5.5 has an outstanding molar extinction coefficient which gives rise to its bright fluorescence.
The molecule contains four sulfo groups that provide hydrophilicity and negative charge to the fluorophore - this minimizes non-specific binding.
The azide group of sulfo-Cyanine5.5 azide can be conjugated with terminal alkynes in the presence of copper(I) catalyst, or with cycloalkynes in copper free strain promoted reaction.
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General properties
| Appearance: | dark colored solid | 
| Mass spec M+ increment: | 984.2 | 
| Molecular weight: | 1099.41 | 
| Molecular formula: | C43H45K3N6O13S4 | 
| Solubility: | good in water, DMF, DMSO | 
| Quality control: | NMR 1H, HPLC-MS (95%) | 
| Storage conditions: | Storage: 24 months after receival at -20°C in the dark. Transportation: at room temperature for up to 3 weeks. Avoid prolonged exposure to light. Desiccate. | 
  Spectral properties
| Excitation maximum, nm: | 673 | 
| ε, L⋅mol−1⋅cm−1: | 195000 | 
| Emission maximum, nm: | 691 | 
| CF260: | 0.09 | 
| CF280: | 0.11 |