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CF®647 Dye

A highly fluorescent far-red dye

Brighter than Cy®5
Water soluble & pH-insensitive
Validated in multi-color STORM

Figure 1. Normalized absorption and emission spectra of CF®647 goat anti-mouse conjugate in PBS.

CF®647 is a cyanine-based far-red fluorescent dye spectrally similar to Cy®5 and Alexa Fluor® 647, with excellent brightness. CF®647 has been validated in multi-color super-resolution imaging by STORM (learn more about CF® dyes for super-resolution imaging). For far-red dyes with excellent brightness and photostability for microscopy applications other than STORM, see CF®633 or CF®640R.

CF®647 Technical Summary

  • Abs/Em Maxima: 650/665 nm
  • Extinction coefficient: 240,000
  • Molecular weight: ~836
  • Laser line: 633 or 635 nm
  • Direct replacement for: Cy®5, Alexa Fluor® 647, DyLight® 649

Figure 2. Apoptotic Jurkat cell stained with NucView® 488 (green) and CF®647 Annexin V (magenta).
Figure 3. Comparison of microtubule imaging using conventional wide-field microscopy with STORM using CF®647 dye conjugate. Images courtesy of Sam Kenny and Professor Ke Xu, College of Chemistry, University of California, Berkeley.

CF is a registered trademark of Biotium. Alexa Fluor and DyLight are registered trademarks of Thermo Fisher Scientific; Cy Dye is a registered trademark of GE Healthcare.

CF®640R Dye < Previous           CF® Dyes Overview           Next > CF®660C & CF®660R Dyes


Lectins, proteins, nucleotides, toxins, and other probes conjugated to our bright & photostable CF® dyes and other labels.

Primary Antibodies

Growing collection of more than 1000 monoclonal antibodies validated in IHC and other applications. Available with bright and photostable CF® dyes, R-PE, APC, PerCP, HRP, AP, biotin, or purified. Affordable 100 uL trial sizes.

CF® Dye Labeled & Biotinylated Secondary Antibodies

Many host/target species and cross-absorption options, featuring a wide spectrum of our bright & photostable CF® dyes or biotin.

CF® Dye Single Label Conjugates for STORM

Secondary antibody conjugates of our STORM-compatible CF® dyes, with an average degree of labeling (DOL) of one, specifically designed for super-resolution imaging by STORM.

Mix-n-Stain™ Antibody Labeling Kits

Mix-n-Stain™ kits use revolutionary technology that dramatically simplifies antibody labeling and requires no purification. The labeling is covalent and stable. Available with your choice of 24 CF® dyes, biotin, FITC, fluorescent proteins, enzymes, or haptens.

CF® Dye Protein Labeling Kits

Everything you need to label and purify antibodies or other proteins. Choose from 19 bright & photostable CF® dyes or biotin.

Reactive CF® Dyes

Our bright, photostable, highly water soluble CF® dyes with a wide selection of colors and functional groups.

Additional conjugates or reactive dye forms may be added on request, contact to inquire.

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CF® Dyes

See our CF® Dye Quick Reference Table for a list of dyes and summary of their features. Our CF® Dye Selection Guide has more detailed information on each CF® dye, and ordering information for our various CF® dye product lines. You can download CF® dye normalized absorption and emission data in Excel format.

Category: Mix-n-Stain™ Antibody Labeling Kits, CF® Dyes

← FAQs
CF® initially was an abbreviation for Cyanine-based Fluorescent dyes. These were the first patented CF® dyes based on cyanine dye structures. Since then, our CF® dye patent portfolio has expanded to include four different fluorescent dye core structures that cover the fluorescence spectrum from UV to NIR.

Category: CF® Dyes

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The exact chemical structures of CF® dyes are currently confidential but will be fully disclosed at a later stage when pending patents become granted. In general terms, the structure of a CF® dye may be divided into two parts: a) dye core structure (i.e. the aromatic ring skeleton that defines the dye’s color or absorption/emission wavelengths), and b) core structure-modifying elements. At present, CF® dyes bear the core structures of coumarin, pyrene, rhodamine or cyanine dyes. Blue fluorescent CF® dyes are based on coumarin or pyrene dye core structure, while green to near-IR CF® dyes are based on either cyanine or rhodamine dye core structures. Core structure-modifying elements refer to various chemical attachments to the core structure and are a key aspect of the CF® dye invention that makes CF® dyes superior to other commercial dyes.

Category: CF® Dyes

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