• Product name
    Anti-Fluorescein antibody (HRP)
    See all Fluorescein primary antibodies
  • Description
    Goat polyclonal to Fluorescein (HRP)
  • Conjugation
  • Specificity
    This antibody reacts with FITC-conjugated proteins.
  • Tested applications
    Suitable for: ELISA, IHC-P, IHC-Fr, WBmore details
  • Immunogen

    Fluorescein conjugated to Goat IgG


  • Form
  • Storage instructions
    Shipped at 4°C. Store at +4°C.
  • Storage buffer
    pH: 7.2
    Preservative: 0.1% Gentamicin sulphate
    Constituents: 0.42% Potassium phosphate, 0.87% Sodium chloride, 1% BSA
  • Concentration information loading...
  • Purity
    Affinity purified
  • Purification notes
    This product was prepared from monospecific antiserum by immunoaffinity chromatography using Fluorescein IgG coupled to agarose beads followed by solid phase adsorption(s) to remove any unwanted reactivities.
  • Clonality
  • Isotype
  • Research areas


Our Abpromise guarantee covers the use of ab6656 in the following tested applications.

The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.

Application Abreviews Notes
ELISA 1/200000.
IHC-P Use at an assay dependent concentration.
IHC-Fr Use at an assay dependent concentration.
WB 1/1000 - 1/5000.


  • Relevance
    Fluorescein is a fluorophore commonly used to label proteins - protein-fluorescein conjugates are not usually susceptible to precipitation. In addition to its relatively high absorptivity, excellent fluorescence quantum yield and good water solubility, fluorescein has an excitation maximum of 494 nm that closely matches the 488 nm spectral line of the argon-ion laser, making it an important fluorophore for confocal laser-scanning microscopy and flow cytometry applications. Its fluorescence is pH sensitive and is significantly reduced below pH 7. Fluorescein emits most strongly between 500 and 550 nm, but it has a relatively broad emission spectrum reaching to over 600 nm. Several derivatives of fluorescein are commonly used, including FITC (fluorescein isothiocyanate), carboxylates and succinimidyl esters.
  • Alternative names
    • FI antibody
    • FITC antibody
    • fluorescein isothyocianate antibody
    • fluorescyl antibody


  • Immunohistochemical analysis of Mouse thymus in which the medullary epithellai cells are labelled with fluorescein-conjugated UEA1 lectin with ab6656. Tissue was fixed with paraformaldehyde and blocked with 1% BSA for 40 minutes at 20°C. Samples were incubated with primary antibody (1/1000) for 1 hour at 20°C.

    See Abreview

  • ab6656 staining GFP in Mouse mammary carcinoma metastasis tissue sections by Immunohistochemistry (IHC-Fr - frozen sections). Perfusion fixed tissue with 4% paraformaldehyde, blocked with 0.5% Perkin-Elmer TNB blocking reagent for 30 minutes at 25°C  and permeabilized with 0.1% Triton X-100. Samples were incubated with primary antibody (1/500) for 30 minutes at 25°C

    Micrograph demonstrates use of ab6662 for detection of GFP-positive tumor cells (LEFT) and an adjacent section after amplification with ab6656 (RIGHT). Images were taken with identical settings on a Leica confocal microscope.

    See Abreview


This product has been referenced in:
  • de Lucas M  et al. Transcriptional Regulation of Arabidopsis Polycomb Repressive Complex 2 Coordinates Cell-Type Proliferation and Differentiation. Plant Cell 28:2616-2631 (2016). In situ hybridization ; Arabidopsis thaliana . Read more (PubMed: 27650334) »
  • Lin WR  et al. The Influence of Bone Marrow-Secreted IL-10 in a Mouse Model of Cerulein-Induced Pancreatic Fibrosis. Biomed Res Int 2016:4601532 (2016). Read more (PubMed: 27314021) »

See all 5 Publications for this product

Customer reviews and Q&As

Abcam guarantees this product to work in the species/application used in this Abreview.
Immunohistochemistry (Formalin/PFA-fixed paraffin-embedded sections)
Mouse Tissue sections (thymus)
Antigen retrieval step
Yes - Tween20
Blocking step
BSA as blocking agent for 40 minute(s) · Concentration: 1% · Temperature: 20°C

Abcam user community

Verified customer

Submitted Feb 29 2016

Thank you for your inquiry and support of our products. The antibody is only tested and guaranteed against derivatives of FITC (Fluorescein isothiocyanate) but it may react with other forms as well. It has not been tested against 6’-FAM. The ant...

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Thank you for contacting us.

Without a direct comparison, it is a little difficult to choose between the two. The ab6656 datasheet also has a review of IHC with TSA amplification on frozen tissue, after applying the antibody at a dilution of...

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Thank you for your enquiry. The concentration of this antibody is 1.000 mg/ml, however the working dilution/concentration needs to be determined since the signal depends on several factors (such as expression levels of the target, sample preparatio...

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Thank you for your phone call today and for your patience while I was in contact with the lab. The lab confirmed that ab6656 has been tested on FITC-conjugated proteins, and so the antibody is appropriate for your studies. I hope this informatio...

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Abcam guarantees this product to work in the species/application used in this Abreview.
Immunohistochemistry (Frozen sections)
Mouse Tissue sections (mouse mammary carcinoma metastasis)
mouse mammary carcinoma metastasis
Yes - 0.1% Triton X-100
Blocking step
Perkin-Elmer TNB Blocking Reagent as blocking agent for 30 minute(s) · Concentration: 0.5% · Temperature: 25°C

Abcam user community

Verified customer

Submitted May 01 2009

Thank you for your enquiry. Yes, I would consider it highly likely that you will be able to use an anti-fluorescein antibody to immunoprecipitate cross linked chromatin associated with your small molecule. You may also wish to consider NChIP as thi...

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Thank you for your enquiry. Yes, the chromogen AEC kit is used after using the HRP conjugated fluorescein antibody in immunohistochemical techniques. If you are doing ELISA then a TMB kit is better.

Sorry, we do not have any data on the specific activity of the HRP.


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