| Abs/Em Maxima | 553/569 nm |
| Extinction Coefficient | 150,000 |
| Flow Cytometry Laser Line | 532, 555 or 568 nm |
| Microscopy Laser Line | 532 or 555 nm |
| Spectrally Similar Dyes | Alexa Fluor® 555, Atto™ 555, CF® 555 Dye, DyLight®549 |
The maleimide derivative of Cy3 dye is the most popular tool for conjugating the dye to a thiol group on antibodies, cysteine-containing peptides and other thiol-containing molecules. The maleimide group specifically and efficiently reacts with reduced thiols (sulfhydryl groups, –SH) at pH 6.5 to 7.5 to form stable thioether bonds.
Cy3 Amine (also sold under Sulfo-Cyanine3 Amine) is a bright, water-soluble, and pH insensitive from pH 4 to pH 10 orange-fluorescent dye. Cy3 conjugates of antibodies, peptides, and proteins can be excited using the 532 nm or 555 nm laser line and visualized with TRITC (tetramethylrhodamine) filter sets. Cy3 conjugates give less background than TAMRA and most other commonly used fluorescent dyes.
This sulfonated dye is also known as sulfo-Cyanine3 Maleimide.
