CF™640R is a rhodamine-based far-red fluorescent dye with excitation and emission maxima very similar to those of Cy®5 and Alexa Fluor® 647 (Figure 1). CF™640R is much brighter than Cy®5 and at least as bright as Alexa Fluor® 647 (Figure 2). A major advantage of CF™640R over Cy®5 and Alexa Fluor® 647 is its exceptional photostability. Cy®5 and Alexa Fluor® 647 are cyanine-based dyes and, like other cyanine dyes in general, have intrinsically poor photostability.
CF™640R is also superior to ATTO™ 647N, another spectrally similar dye frequently used in single-molecule imaging. As shown in Figures 2 and 3, CF™640R is significantly brighter and more photostable than the ATTO™ dye. The combination of excellent brightness and photostability makes CF™640R ideal for confocal microscopy, single- molecule imaging and other demanding applications based on fluorescence detection.
A full selection of reactive dyes, secondary antibodies, antibody labeling kits, and other bioconjugates including phalloidins, Annexin V and α-bungarotoxin are available for CF™ dyes.
- Abs/Em Maxima: 642/662 nm
- Extinction coefficient: 105,000
- Molecular weight: ~832
- Flow cytometry laser line: 633, 635 or 640 nm
- Microscopy laser line: 633, 635 or 640 nm
- Direct replacement for: Cy®5, Alexa Fluor® 647 and ATTO™ 647N
- Has the best photostability among dyes with Cy®5-like spectra
- Yields highly fluorescent protein conjugates
- Very water-soluble and pH-insensitive