Mix-n-Stain™ CF® Dye Small Ligand Labeling Kits

For CF® dye, cyanine dye, FITC, biotin, DNP, and dig kits, see the Mix-n-Stain™ Kit Compatibility and Protocol Selection Flowchart, below. We also recommend downloading the updated Product Protocol and completing the pre-labeling checklist to find the right protocol and kit size to use for each antibody you wish to label. Learn more about CF® dyes on our CF® Dye Technology Page, or download the CF® Dye Brochure.

Note that Mix-n-Stain™ Maxi 1 mg Scale Kits, Mix-n-Stain™ Fluorescent Protein Labeling Kits (R-PE, APC, PerCP, or tandem dye), Mix-n-Stain™ Enzyme Labeling Kits (AP, HRP, GOx) have different compatibility requirements and labeling protocols. Check the protocol for your kit to verify that your antibody is compatible with labeling, then choose a kit size that matches your the amount of antibody you wish to label.

Category: Mix-n-Stain™ Antibody Labeling Kits

CF® dyes are highly water soluble, small organic dyes designed by scientists at Biotium for labeling proteins and nucleic acids. With a series of over 20 colors (and growing), many of our CF® dyes are brighter and more photostable than competing dyes. For more information please see the product flyers for individual CF® dyes, the CF® Dye Selection Guide, and our CF® Dye FAQs.

Category: Mix-n-Stain™ Antibody Labeling Kits

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

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

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

There is no simple answer to this question as the quantum yield of a fluorescent dye can vary widely, depending on the dye’s micro-environment. For example, the quantum yield of a dye attached to a protein may be very different from the quantum yield of the free dye. For dyes attached to a protein, the quantum yield is highly dependent on how many molecules of the dye are attached to the protein (i.e. degree of protein labeling). In general, a higher degree of protein labeling leads to a lower dye quantum yield due to fluorescence quenching via dye-to-dye interaction. For this reason, as the degree of labeling increases, fluorescence intensity of the labeled protein will eventually reach a maximum and start to decline thereafter. In fact, one of the best ways to compare the relative quantum yields of different dyes is to plot the total fluorescence of the labeled proteins as a function of degree of labeling by the dyes as we have done with CF® dyes and other commercial dyes. CF® dyes generally give higher slopes than other commercial dyes in the plots, suggesting less quantum yield decline with increasing degree of protein labeling.

Category: CF® Dyes