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CF®568 Dye

Outshines Alexa Fluor® 568

Much brighter conjugates than Alexa Fluor® 568
Excellent photostability for demanding imaging applications
Compatible SIM, TIRF, and multicolor STORM

Figure 1. Normalized absorption and emission spectra of CF®568 goat anti-mouse antibody conjugate in PBS.

CF®568 is a red fluorescent dye with an excitation spectrum optimally matching the 568 nm laser line. Antibody conjugates of the dye are much brighter than those of Alexa Fluor® 568. CF®568 is also more photostable than Alexa Fluor® 568, making CF®568 a much better choice for demanding applications, such as confocal and single molecule imaging. CF®568 has been validated in super-resolution imaging by SIM, TIRF, and multicolor STORM, and produces better STORM images than Cy®3b (learn more about CF® Dyes for Super-Resolution Imaging). See CF®568 product lines below.

CF®568 Technical Summary

  • Abs/Em maxima: 562/583 nm
  • Extinction coefficient: 100,000
  • Molecular weight: ~714
  • Excitation laser line: 532 nm or 568 nm
  • Direct replacement for: Alexa Fluor® 568, ATTO 565, Rhodamine Red

Figure 2. CF®568 produces brighter antibody conjugates than Alexa Fluor® 568. Jurkat cells were stained with mouse anti-CD3 or isotype control, followed by CF®568 or Alexa Fluor® 568 goat anti-mouse conjugates with varying degrees of labeling (DOL, dye molecules per protein molecule). Fluorescence was analyzed on a BD FACSCalibur™ flow cytometer in the FL2 channel; bars represent geometric mean fluorescence.
Figure 3. CF®568 is more photostable than Alexa Fluor® 568. Jurkat cells were stained with biotinylated anti-CD3 antibody followed by CF®568 or Alexa Fluor®568 streptavidin conjugate. Cells were continuously exposed to mercury arc lamp excitation through a Cy®3 filter cube. Images were captured every 15 seconds for 5 minutes, and fluorescence intensity was normalized to time zero.

Figure 4. MCF-7 cells stained with CF®568 monoclonal anti-Ep-CAM (EGP40/826) (red) and Hoechst (blue).
Figure 5. HeLa cells stained with NucSpot® 470 (green) and CF®568 phalloidin (red).
Figure 6. Section of rat intestine stained with CF®568 phallodin (red). Nuclei are stained with DAPI (blue).

CF is a registered trademark of Biotium, Inc; Alexa Fluor is a registered trademark of Thermo Fisher Scientific.

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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.

Secondary & Anti-Tag Antibodies

Wide selection of species reactivities and anti-tag antibodies. Choose from more than 20 CF® dyes, R-PE, APC, HRP, AP or biotin. Highly cross-adsorbed, F(ab’)2 fragments, and isotype-specific options. Affordable 50 uL trial sizes.

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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