• Product name

    Anti-IgM Affibody® Molecule
  • Specificity

    This product binds to human IgM.
  • Tested applications

    Suitable for: ELISA, Othermore details
  • Species reactivity

    Reacts with: Human
  • General notes

    This product is a recombinant protein produced in E.coli.

    What are Affibody Molecules?
    Affibody® affinity ligands are unique research reagents, produced using innovative protein-engineering technologies. They are small, simple proteins composed of a three-helix bundle based on the scaffold of one of the IgG-binding domains of Protein A. Protein A is a surface protein from the bacterium Staphylococcus aureus. This scaffold has excellent features as an affinity ligand and can be designed to bind with high affinity to any given target protein. The domain consists of 58 amino acids, 13 of which are randomized to generate Affibody® libraries with a large number of ligand variants. Thus, the libraries consist of a multitude of protein ligands with an identical backbone and variable surface-binding properties. In function, Affibody® Molecules mimic monoclonal antibodies. Compared to antibodies, the most striking dissimilarity of Affibody® Molecules is the small size. Affibody® Molecules have a molecular weight of 6kDa, compared to the molecular weight of antibodies, which is 150kDa. In spite of its small size, the binding site of Affibody® Molecules is similar to that of an antibody. The advantages of Affibody® Molcules over antibodies are: -their small size -the simple structure of the molecules -its robust physical properties; able to withstand a broad range of analytical conditions, including extreme pH and elevated temperature -its ability to fold correctly intracellularly -the fast and cost effective production in bacteria -the potential to couple Affibody® Molecules in multimeric constructs Affibody® Molecules have highly competitive properties for applications within affinity purification, sample preparation, protein detection and in vitro diagnostics.

    This Anti-Fibrinogen Affibody® Molecule is modified with a unique C-terminal cysteine for directed single-point chemical modification, facilitating coupling to matrices. However, tail-to-tail dimers are spontaneously generated via a disulphide bridge between the C-terminal cysteines. Prior to coupling via the C-terminal the Affibody® Molecule needs to be reduced to expose the reactive cysteine residue. Recommended reducing condition is 20mM DTT at a pH above 7.5 and incubation at room temperature for 2 hours. Remove excess DTT by passage through a desalting column, not by dialysis. ab50345 is a secondary antibody suitable for use in the process of detecting this Affibody® Molecule.



  • Form

  • Storage instructions

    Shipped at 4°C. Store at +4°C short term (1-2 weeks). Store at -20°C or -80°C. Avoid freeze / thaw cycle.
  • Storage buffer

    pH: 7.4
    Constituent: PBS
  • Concentration information loading...
  • Purification notes

    The purity of this product is >98% as determined by SDS-PAGE and RP-HPLC analysis.
  • Research areas

  • Relevance

    IgM normally constitutes about 10% of serum immunoglobulins. IgM antibody is prominent in early immune responses to most antigens and is largely confined to plasma due to it's large size. Monomeric IgM is expressed as a membrane bound antibody on the surface of B cells and as a pentamer when secreted by plasma cells. Due to it's high valency IgM is more efficient than other isotypes is binding antigens with repeating epitopes (virus particles and red blood cells) and is more efficient than IgG in activiating the complement pathway. The gene for the mu constant region contains four domains separated by short intervening sequences. IgM measurement yields information about the body's immediate resistance and response to infection as well as information related to specific diseases. Decreased levels are associated with immune deficiency states, hereditary deficiencies, and myeloma. Increased levels can be associated with Waldenstrom's macroglobulinemia, chronic infection and hepatocellular disease.
  • Cellular localization

    Cell Membrane and Secreted
  • Alternative names

    • Immunoglobin heavy chain constant region mu
    • AGM1
    • Constant region of heavy chain of IgM
    • DKFZp686I15196
    • DKFZp686I15212
    • FLJ00385
    • Ig mu chain C region
    • IGHM
    • IgM heavy chain constant region
    • Immunoglobin heavy constant mu
    • Immunoglobulin mu
    • MGC104996
    • MGC52291
    • MU
    • VH
    see all
  • Database links


Our Abpromise guarantee covers the use of ab36088 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
AP Use at an assay dependent concentration.
ELISA Use at an assay dependent concentration.
Other Use at an assay dependent concentration.

This Anti-IgM Affibody® Molecule is an ideal affinity ligand as capture reagent in ELISA and as capture molecule in affinity chromatography.


  • Results quantitative ELISA

    The Anti-IgM Affibody® molecule can be used as capture reagent in a sandwich ELISA in combination with a mouse anti- IgM antibody as the detection reagent. Titration of IgM gives a sigmoid curve with a sensitivity of 2.0 ng IgM/ml (defined as two times background value).


This product has been referenced in:

  • Gomes de Castro MA  et al. Differential organization of tonic and chronic B cell antigen receptors in the plasma membrane. Nat Commun 10:820 (2019). Read more (PubMed: 30778055) »
  • Somerfield J  et al. A novel strategy to reduce the immunogenicity of biological therapies. J Immunol 185:763-8 (2010). Read more (PubMed: 20519651) »
See all 2 Publications for this product

Customer reviews and Q&As

1-2 of 2 Q&A


Expiration date: 18/07/2012
I am very pleased to hear you would like to accept our offer and test ab36088 in IP (mouse, rat, human). This code will give you 1 free PRIMARY ANTIBODY before the expiration date. To redeem this offer, please submit an Abreview for IP (mouse, rat, human) and include this code in the “Additional Comments” section so we know the Abreview is for this promotion. For more information on how to submit an Abreview, please visit the site: www.abcam.com/Abreviews.
Remember, we publish both positive and negative Abreviews on our datasheets so please submit the results of your tests. The code will be active once the Abreview has been submitted and can be redeemed in one of the following ways: 1) Call to place your order and mention the code to our customer service department; 2) Include the code in your fax order; 3) Place your order on the web and enter the promotional code.
Any feedback that you can provide will be greatly appreciated, whether positive or negative. If you have any further questions, please do not hesitate to contact us. We look forward to receiving your Abreview and wish you luck with your research.
The terms and conditions applicable to this offer can be found here: www.abcam.com/collaborationdiscount.

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Thank you for your enquiry and your interest in products.
If the customer wants to use IgM for immunoprecipitation, and for some reason wants to use Affibody® Molecules rather than Anti-Anti-IgM Antibodies, we recommend testing to use Anti-IgM Affibody® Molecule, biotinylating this at the C-terminal Cys and coupling it to some type of streptavidin coated beads. We have not tested this ourselves but we predict it would work. IgM will still be active when bound to Anti-IgM Affibody® Molecule.
The other questions are not relevant if the customer uses this approach, but the answers would be that Affibody® Molecules do not bind to Protein A, G or L.
Affibody® Molecules are based on the 58 aa three-helix bundle of Domain B of Protein A. Some of the amino acids in the binding site of that domain have been replaced. That is, the Anti-IgM Affibody® Molecule, as all Affibody® Molecules, is an engineered protein.
I hope this will be useful.

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