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Blocking Reagents


ChemiBlock™ Reagents

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ChemiBlock™ reagents, acquired by us from Chemicon in 2006, are well recognized for their ability to block human anti-mouse antibodies (HAMA) and other HAMA-like agents in patient samples. We are proud to announce the availability of new, reinforced reagents designed to minimize interfering antibody effects on immunoassays. These reagents contain proprietary additives that actively combine with interfering antibodies to knock out HAMA, heterophilic, and other interfering antibodies.

View Our Scientific Poster Presented at AACC 2012:
EC50 of Reagents Used in Blocking Heterophilic Interference in Immunoassays

Read our Brochure:
Controlling Interfering Antibodies in Diagnostic Assays

For more information on blocking:
Probumin® BSA Products

Active Blocking Reagents
Designed to actively block interfering antibodies (HAAAs, RF, Heterophiles) by neutralizing them, allowing the binding of analyte/antigen to capture and detector antibodies to occur. Since active blocking reagents contain specific antibodies, they may typically be used in lower concentrations than passive blocking reagents.
Super ChemiBlock™ Heterophile Blocking Agent Catalog No. CBS-K
Goat anti-Human IgG Fc Fragment (Gamma Globulin Fraction) Catalog No. AB728-K
Goat anti-Human IgG Fc Fragment. Affinity purified. (Gamma Globulin Fraction) Catalog No. AP113-K

Passive Blocking Reagents
Passive blocking reagents comprise normal animal immunoglobulins and other components that essentially overwhelm and reduce the concentration of interfering antibodies by providing alternate binding sites to those of the detector and capture antibodies. Passive blocking reagents may be combined and/or used with active blockers to optimize formulations for specific assays.
ChemiBlock™ II Heterophile Blocking Agent Catalog No. CBII-K
Mouse IgG (Purified) Catalog No. PP54-K
Rabbit IgG (Gamma Globulin Fraction) Catalog No. PP63-K
Rabbit IgG (Purified) Catalog No. PP64-K
Equine IgG (Gamma Globulin Fraction) Catalog No. PP301-K

Isotype Specific Mouse IgG
Purified Mouse IgG1. Affinity purified. Catalog No. PP100-K
ChemiBlock™ Blend Heterophile Blocking Agent. Affinity purified. Catalog No. PP1230-K

Eliminate False Positives with ChemiBlock™ Reagents


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