| Abs/Em Maxima | 678/694 nm |
| Extinction Coefficient | 190,000 |
| Flow Cytometry Laser Line | 633 nm or 647 nm |
| Microscopy Laser Line | 633 nm or 647 nm |
| Spectrally Similar Dyes | Alexa Fluor® 680, IRDye® 680RD, CF™ 680 Dye |
Cy5.5 Maleimdie (also sold under sulfo-Cyanine5.5 Maleimide name) is a bright and photostable near-IR dye that is spectrally similar to Alexa Fluor® 680, DyLight® 680, and IRDye® 680 dye. Cy5.5 NHS Ester is completely water-soluble and often a reagent of choice for labeling antibodies, peptides, and proteins that are sensitive toward organic co-solvents. Cy5.5 conjugates are pH insensitive from pH 4 to pH 10 and produce 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.
Cy5.5 spectrally is almost identical to Alexa Fluor® 680, CF® 680 Dye, IRDye® 680 or any other Cyanine5.5 based fluorescent dyes, and can be used as a less expensive alternative to these dyes.
This sulfonated dye is also known as sulfo-Cyanine5.5 Maleimdie.
