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AF Dye-CD Antibody Conjugates
AF Dye-CD antibody conjugates are primary antibodies pre-labeled with our XFD dye series. These conjugates are designed for direct immunofluorescence detection of cluster of differentiation (CD) markers on cell surfaces. XFD dyes are spectrally equivalent to Alexa Fluor® dyes, providing researchers with high-quality, ready-to-use reagents for flow cytometry, immunofluorescence microscopy, and immunophenotyping applications. These conjugates eliminate the need for secondary antibody staining, simplifying multicolor panel design and reducing experimental time.
Fluorophore
Ex/Em (nm)
Laser Line
Best For
Common Filters
XFD488
493/517
488 nm (Blue)
High brightness, standard green channel
FITC
XFD532
532/553
532 nm (Green)
Yellow-green emission, multiplex panels
Cy3
XFD555
555/580
532/561 nm
Orange emission, excellent photostability
TRITC/Cy3
XFD594
590/617
561/594 nm
Red emission, low background autofluorescence
Texas Red
XFD647
650/668
633/640 nm (Red)
Far-red emission, minimal spectral overlap
Cy5/APC
XFD700
696/719
633/640 nm (Red)
Near-IR emission, extended multiplex panels
Cy5.5
XFD750
749/775
633/640 nm (Red)
Near-IR, deep tissue imaging applications
Cy7
AF Dye-CD Antibody Conjugates Overview

AF Dye-conjugated CD antibodies are directly labeled primary antibodies targeting cluster of differentiation antigens expressed on immune cells and other cell types. These conjugates utilize AAT Bioquest's XFD dye series, which are bright, photostable fluorescent dyes that are spectrally equivalent to Alexa Fluor® dyes, offering researchers reliable performance for immunophenotyping, cell sorting, and multicolor flow cytometry applications.
  • Direct detection format — No secondary antibody required, reducing protocol steps and potential background
  • Validated for flow cytometry — Optimized dye-to-protein ratios ensure consistent, reproducible results
  • Broad spectral coverage — Available in multiple fluorophore options (XFD488, XFD555, XFD594, XFD647, XFD700, XFD750) for flexible panel design
  • Spectrally matched to Alexa Fluor® dyes — Compatible with existing instrument configurations and filter sets
  • High photostability — Excellent resistance to photobleaching for extended imaging sessions
  • Low background — Minimal non-specific binding for improved signal-to-noise ratios
Common CD Marker Applications

CD markers serve as critical identifiers for characterizing immune cell populations. The table below summarizes common CD targets and their primary applications in immunophenotyping research.
CD Marker
Synonyms
Primary Cell Types
Common Applications
CD3
T3
T lymphocytes
Pan-T cell marker, T cell activation studies
CD4
T4, Leu-3
Helper T cells, monocytes
T helper cell identification, HIV research, immunocompetence assessment
CD8
T8, Leu-2
Cytotoxic T lymphocytes, NK cells
CTL identification, immune monitoring, tumor-infiltrating lymphocyte analysis
CD14
LPS receptor, Monocyte marker
Monocytes, macrophages
Monocyte gating, inflammation studies, bacterial response assessment
CD19
B4
B lymphocytes
Pan-B cell marker, lymphoma typing, B cell lymphoma classification
CD20
B1, Bp35
B lymphocytes
B cell development, rituximab therapy monitoring, B cell malignancy detection
CD25
IL-2Ralpha
Activated T cells, regulatory T cells (Tregs)
Regulatory T cell identification, T cell activation marker, immunosuppression studies
CD34
Mucosialin
Hematopoietic stem and progenitor cells
Stem cell enumeration, transplant monitoring, hematopoietic assessment
CD45
LCA (Leukocyte Common Antigen)
All leukocytes
Pan-leukocyte gating, lymphoma diagnosis, immune cell enumeration
CD56
NCAM (Neural Cell Adhesion Molecule)
Natural killer (NK) cells, NKT cells
NK cell identification, immunotherapy monitoring, cancer immunology studies
AF Dye-CD Antibody Product Table

The table below lists all available AF Dye-CD antibody conjugates organized by CD target. AF Dye-CD antibody conjugates utilize AAT Bioquest's XFD dyes, which are chemically similar and spectrally equivalent to Alexa Fluor® dyes (Alexa Fluor® is a trademark of ThermoFisher Scientific). Click any clone name to view the product page.
iFluor® Dyes for Superior Performance

For researchers seeking superior fluorescence performance, AAT Bioquest's iFluor® dye series offers enhanced brightness and photostability compared to traditional fluorophores. iFluor® conjugates are available across the full visible spectrum and represent next-generation alternatives to Alexa Fluor® and other conventional dyes.
  • Superior brightness — Up to 2× brighter than comparable Alexa Fluor® dyes in many applications
  • Enhanced photostability — Extended imaging without significant signal loss
  • Excellent water solubility — Minimal aggregation and non-specific binding
  • Optimized for biological applications — Designed specifically for antibody conjugation and cellular imaging

This document (01.0281.251203r1) was last updated on Thu Feb 12 2026. All trademarks and registered trademarks mentioned herein are the property of their respective owners.