Products & Reviews

Whole IgG antibodies are isolated as intact molecules from antisera by affinity chromatography.

Normal serum can be used as a blocking agent to reduce background. Normal serums are lipid extracted to improve clarity, dialyzed against phosphate buffered saline (PBS) containing sodium azide, and freeze-dried. Normal serum diluted to 5% (v/v) in PBS is strongly recommended as a blocking agent to reduce background from non-specific, conserved-sequence, and/or Fc-receptor binding. Best results are obtained with diluted nor…

Using biotinylated secondary antibodies along with conjugated streptavidin is a robust means of signal amplification. Conjugates of streptavidin are recommended for use with Biotin-SP-conjugated affinity-purified secondary antibodies and Biotin-SP-conjugated ChromPure proteins. We offer a comprehensive list of fluorophores and enzymes conjugated to streptavidin for use in enzyme immunoassays, immunohistochemistry, flow c…

F(ab')2 fragments of antibodies are generated by pepsin digestion of whole IgG antibodies to remove most of the Fc region while leaving intact some of the hinge region. Used for specific applications, such as to avoid binding of antibodies to live cells with Fc receptors or to Protein A or Protein G. 

Fab fragment antibodies are generated by papain digestion of whole IgG antibodies to remove the entire Fc portion, including the hinge region. Block endogenous immunoglobulins on cells, tissues , or other surfaces. Block exposed immunoglobulins in multiple labeling experiments using primary antibodies from the same species. Fab-label primary antibodies in solution without compromising activity.

Bovine serum albumin (BSA) is used extensively as a carrier protein to dilute antibodies and as a general protein blocking agent in immunoassays and immunodetection protocols. Our IgG-free BSA, which is also protease-free, should alleviate many of the problems associated with using BSA. Many preparations of BSA, even some of the highest purity grades, contain IgG that may become an antigen for cross-reacting secondary an…

ChromPure is our trade name for highly purified proteins from the serum of non-immunized animals.

Antisera to Enzymes, Serum Proteins, & Whole Serums. Polyclonal antisera from immunized hosts are lipid extracted to improve clarity, salt fractionated, dialyzed against phosphate buffered saline containing sodium azide, and freeze-dried. Antisera against whole serums are obtained by immunizing host animals with whole serum. Antisera against whole IgG molecules [i.e. Anti-IgG (H+L)] are recommended for bridging PAP to prima…

Solid-Phase Immunoadsorbent Gels. Highly purified IgG from the serum of non-immunized animals is coupled to cyanogen bromide-activated 4% agarose gels for use in preparing affinity-purified antibodies or removing cross-reactive antibodies. Proteins are coupled at a concentration of 1 mg protein per ml of settled gel, and are packaged in phosphate buffered saline with sodium azide.

Peroxidase-Anti-Peroxidase (PAP) Soluble Immune Complexes. Whole antisera against IgG (H+L) are recommended for bridging PAP to primary antibodies. Antisera against IgG (H+L) or against the F(ab') 2 fragments of IgG will also bridge PAP to IgM primary antibodies (such as IgM monoclonal antibodies) by virtue of common light-chain recognition.