Omalizumab mAb-Based ELISA Assay


The Omalizumab ELISA Assay Kit is an enzyme immunoassay for the specific and precise measurement of free Omalizumab in serum and plasma samples. This assay utilizes the specific monoclonal antibodies as the coating material on the microtiter plate so this assay specifically measures only Omalizumab and no other TNF-a therapeutic.  The Eagle Biosciences Omalizumab ELISA Assay Kit is for research use only and not to be used in diagnostic procedures.

Omalizumab mAb-Based ELISA Assay

The Omalizumab mAb-Based ELISA Assay is For Research Use Only

Size: 1 x 96 wells
Sensitivity: 1 ng/mL
Dynamic Range: 3 – 100 ng/mL
Incubation Time: 2 hours
Sample Type:  Serum, Plasma
Sample Size: 10 µL
Alternative Name: Xolair

Assay Background

Omalizumab (trade name Xolair®) is a recombinant DNA-derived humanized IgG1κ monoclonal antibody and it binds to human immunoglobulin E (IgE). The molecular weight of omalizumab is 149 kilodlatons and is produced by Chinese hamster ovary cell suspension culture. Omalizumab inhibits the binding of IgE to IgE receptor (FcεRI) on the surface of mast cells and basophils. Therefore, the Omalizumab is expected to limit the degree of release of mediators of the allergic response from the FcεRI bearing cells.

This ImmunoGuide Omalizumab ELISA (mAb-based) is developed for the specific measurement of Omalizumab in serum, plasma and other biological fluids by the advantage of using a site-directed IG-Ulkr4H1 mouse monoclonal antibody (mAb) specific for Omalizumab only. Binding of Omalizumab to the solid phase, pre-coated with IG-Ulkr4H1, is inhibited by human IgE in a concentration dependent manner. Therefore, the ImmunoGuide Omalizumab ELISA (mAb-based) measures the free form of Omalizumab only. The choice of specifically measuring the free form allows investigators to analyze the concentration-effect relationship. The ImmunoGuide Omalizumab ELISA  (mAb-based) kit can be efficiently used for measuring free Omalizumab levels in serum and plasma.

The kit is shipped at ambient temperature and should be stored at 2-8°C. Keep away from heat or direct sun light. The microtiter strips are stable up to the expiry date of the kit in the broken, but tightly closed bag when stored at 2–8°C.

Related Products

Omalizumab (Xolair) ELISA Assay Kit
Anti-Omalizumab (Xolair) ELISA Assay Kit
Ranibizumab mAb-based ELISA Assay

Additional Information

Assay Principle

This Eagle Biosciences ELISA Assay Kit is based on Omalizumab-specific monoclonal antibody (catcher Ab, ImmunoGuide clone Ulkr4H1). Standards and diluted samples are incubated in the microtiter plate coated with IG-Ulkr4H1 mAb. After incubation, the wells are washed. A horseradish peroxidase (HRP)-conjugated anti-human IgG monoclonal antibody is added and binds to the Fc part of Omalizumab. Following incubation, wells are washed and the bound enzymatic activity is detected by addition of a chromogen-substrate. The color developed is proportional to the amount of Omalizumab in the sample or standard. Results of samples can be determined by using the standard curve. Binding of Omalizumab to the solid phase, precoated with IG-Ulkr4H1, is inhibited by human IgE in a concentration dependent manner. Therefore, the ImmunoGuide Omalizumab ELISA (mAb-based) measures the free form of Omalizumab only.

Typical Standard Curve

Omalizumab mAb-Based ELISA Assay


Product Manual


Please note: All documents above are for reference use only and should not be used in place of the documents included with this physical product. If digital copies are needed, please contact us.



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