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iFluor® Labeling Dyes
AAT Bioquest iFluor® dyes are a series of highly water-soluble fluorescent dyes for covalently labeling biomolecules such as proteins, antibodies, peptides, and nucleic acids. Available in a variety of excitation–emission profiles spanning the UV–visible to near-infrared spectrum, there is an iFluor® dye to match any instrument setup and many combinations for multiplex detection. Conjugates made with iFluor® dyes exhibit superior brightness and photostability, matching or exceeding Alexa Fluor® conjugates and other spectrally similar conjugates. Use iFluor® products for immunofluorescence assays, cell imaging, and flow cytometric applications.
Fig. 1
ifluor staining
Actin filaments visualized with Phalloidin-iFluor® conjugates. F-actin, nucleus, and lysosomes were stained with Phalloidin iFluor® 488, Nuclear Blue™ DCS1, and LysoBrite™ Red, respectively.
iFluor® Reactive Dyes
iFluor® reactive dyes may be covalently labeled to biomolecules without self-quenching, producing intensely fluorescent conjugates. They are widely used to modify amino acids, peptides, proteins (in particular antibodies), oligonucleotides, nucleic acids, carbohydrates and other biological molecules. iFluor® reactive dye formats include amine-reactive succinimidyl ester, thiol-reactive maleimide, and more.
The figure and tables below show the range of available iFluor® reactive dyes, their excitation and emission maxima, and their fluorophore equivalents to assist you in selecting the best fluorophore for labeling proteins, antibodies, and other biopolymers, as well as derivatizing low molecular weight molecules.
Fig. 2
Fig. 2
Emission spectra of iFluor® fluorescent dye family, ranging from NUV to IR. Click here to compare iFluor® spectra.
ReadiLink™ Rapid and xtra Rapid iFluor® Antibody Labeling Kits
ReadiLink™ Rapid iFluor® Antibody Labeling Kits and BSA-compatible ReadiLink™ xtra Rapid iFluor® Antibody Labeling Kits provide a quick and convenient method to label microscale volumes of antibodies with our superior iFluor® dyes. The unique chemistry of ReadiLink™ kits enables researchers to effortlessly label and recover 100% of their antibodies without a purification step. Since ReadiLink™ conjugates are covalently labeled, they are stable for long-term storage. They are ideal for demanding applications, including fluorescent microscopy, multi-color imaging, multiplex flow cytometry, primary detection, IHC, FISH, ELISAs, and more. Also available are ReadiLink™ Rapid and xtra Rapid Antibody Labeling kits for conjugation of mFluor™ dyes, Alexa Fluor® dyes, other fluorescent dyes, biotin, BSA, and KLH.
Key Features of ReadiLink™ Rapid Antibody Labeling Kits
  • ReadiLink™ xtra Rapid iFluor® Antibody Labeling Kits are compatible with BSA and other stabilizing proteins
  • Label monoclonal antibodies, polyclonal antibodies, or other proteins
  • Quick and simple two-step labeling protocol, no chemistry or conjugation experience necessary
  • Useful for labeling 100 µg of antibody (two separate labeling reactions of 50 µg antibody)
  • 100% antibody recovery, NO purification of the product is required
Fig. 3
ReadiLinkWorkflow
ReadiLink™ Rapid Antibody Labeling Kit workflow (figure drawn in BioRender).
Additional Resources
Custom Conjugation and Synthesis Services
AAT Bioquest offers a wide selection of labels for bioconjugation, including iFluor® dyes, traditional fluorophores, hapten molecules, and enzymes, along with a choice of labeling chemistries to satisfy any research need. In addition to our catalog products, we offer custom services, for both bioconjugation and dye development and synthesis. For a list of our custom services, please see here.
Fluorescence Spectrum Viewer
Need assistance selecting the best fluorophore for your experiment? Use our Fluorescence Spectrum Viewer to:
  • View and compare fluorophores and fluorescent proteins for biological applications
  • Check spectral compatibility
  • Add multiple excitation and emission filters
  • Save spectra configuration as a PNG or hyperlink
This document (01.0102.211211r2) was last updated on Sat Feb 28 2026. All trademarks and registered trademarks mentioned herein are the property of their respective owners.
Featured products
NameExcitation (nm)Emission (nm)
iFluor® 488 succinimidyl ester491516
iFluor® 860 succinimidyl ester853878
iFluor® 350 succinimidyl ester345450
iFluor® Labeling Dyes
iFluor® Reactive Dyes
ReadiLink™ Rapid and xtra Rapid iFluor® Antibody Labeling Kits
Additional Resources
Custom Conjugation and Synthesis Services
Fluorescence Spectrum Viewer