AAT Bioquest's iFluor® dyes are a comprehensive family of water-soluble fluorescent dyes engineered for covalent labeling of proteins, antibodies, peptides, nucleic acids, and other biomolecules. With over 45 spectrally distinct dyes --- including the iFluor® Ultra series --- spanning from UV to near-infrared, iFluor® dyes deliver superior brightness, photostability, and water solubility compared to classic fluorophores such as FITC, Alexa Fluor®, Cy® dyes, and Texas Red®.

iFluor® dyes are trusted across a wide range of biological research applications:

iFluor® dyes consistently outperform legacy fluorophores in head-to-head comparisons across brightness, photostability, and conjugation yield.

iFluor® 488 is a direct replacement for FITC with dramatically higher fluorescence intensity and photostability in both microscopy and flow cytometry.

iFluor® 594 offers an exceptionally high extinction coefficient (200,000 M⁻¹cm⁻¹) and conjugation yield, making it the brightest option in the orange-red channel.

iFluor® 700 provides stronger 633 nm laser absorption and a higher stain index than Alexa Fluor® 700, making it ideal for multicolor flow cytometry panels.

Scientists use both extinction coefficient (EC) and quantum yield (QY) to evaluate fluorophore performance, as Brightness = EC x QY. The table below lists all iFluor® and iFluor® Ultra dyes with known spectral data, sorted by excitation wavelength.

ReadiLink™ kits let you label your own antibodies with iFluor® dyes in under 30 minutes with no purification required. They use Tide Quencher (TQ) technology to quench unreacted free dye, eliminating background fluorescence without column purification.

Buccutite™ kits are designed for conjugating phycobiliproteins (PE, APC) and enzymes (HRP, ALP), enabling custom PE and APC tandem conjugation with iFluor® dyes as energy-transfer acceptors.

iFluor® secondary antibody conjugates are available as goat anti-mouse IgG (H+L) and goat anti-rabbit IgG (H+L) in 20+ iFluor® colors, plus goat anti-human IgG in select colors. Optimized fluorophore-to-protein ratios provide maximum brightness with minimal quenching. Compatible with indirect immunofluorescence, Western blotting, ELISA, and tissue section imaging.

Phalloidin-iFluor® conjugates are high-affinity F-actin probes for visualizing and quantifying actin filaments in fixed, permeabilized cells and tissue sections. Phalloidin selectively binds F-actin over monomeric actin, stabilizing filaments and preventing depolymerization. Effective at nanomolar concentrations for high-contrast cytoskeletal imaging.

Available in 15 iFluor® colors: 350, 405, 488, 514, 532, 555, 568, 594, 633, 647, 660, 680, 700, 750, 790

Annexin V-iFluor® conjugates detect early-stage apoptosis by binding phosphatidylserine (PS) exposed on the outer leaflet of the plasma membrane --- detectable before morphological changes become observable. Compatible with both flow cytometry and fluorescence microscopy.

Available in 10 iFluor® colors: 350, 488, 555, 568, 594, 633, 647, 680, 700, 750

iFluor® streptavidin conjugates are high-affinity reagents for biotin-based detection systems. Used as second-step reagents with biotinylated primary antibodies for indirect immunofluorescent staining. Includes tandem variants such as APC-iFluor® 750 and RPE-iFluor® 647/750 streptavidin conjugates.

Available in 19+ iFluor® colors spanning UV to near-infrared (350 through 860)

Wheat germ agglutinin (WGA) conjugates bind N-acetyl-D-glucosamine and sialic acid residues. Applications include plasma membrane staining, yeast bud scar labeling, fibrotic scar tissue visualization, and Gram bacterial cell membrane labeling.

Available in 10 iFluor® colors: 350, 488, 532, 555, 594, 647, 680, 700, 750, 790

iFluor® dUTP conjugates are dye-modified deoxyuridine 5'-triphosphates for enzymatic incorporation into DNA via nick translation, reverse transcription, random primed labeling, or PCR. Used for FISH probe production and microarray-based experiments.

Available in 7 iFluor® colors: 350, 440, 488, 532, 560, 570, 647 --- plus PEG12-linked variants (488, 555, 647)

Pre-conjugated iFluor®-CD antibodies are ready for immunophenotyping by flow cytometry and fluorescence microscopy. Ready-to-use format with pre-validated specificity and optimized fluorophore-to-protein ratios.

iFluor® dyes serve as energy-transfer acceptors in tandem conjugates with PE, APC, and PerCP, extending the spectral range of these bright phycobiliproteins into far-red and near-infrared channels for multicolor flow cytometry.

Helixyte™ iFluor® dyes enable non-enzymatic fluorescent labeling of DNA, RNA, and oligonucleotides. The dyes react with the N7 position of guanine residues to form a stable coordination complex between the nucleic acid and the fluorophore, with no enzymatic incorporation required. Six fluorophore options are available for multiplexing.

Power Styramide™ (PSA™) is an enzymatic amplification technology that couples the brightness and photostability of iFluor® dyes to a horseradish peroxidase (HRP)-mediated Styramide™ reaction. Reactive Styramide™ radicals are generated locally and covalently deposited near the target site, producing over 100-fold signal enhancement compared to conventional ICC, IHC, or ISH methods with minimal background noise.

PSA™ is especially valuable for detecting low-abundance targets --- weakly expressed proteins, rare tumor markers, and circulating tumor cells in blood samples --- that might otherwise escape detection with conventional methods. Its robust, reproducible nature and high-throughput compatibility support large-scale analyses without compromising image quality.