All Purified Antibodies are NOT Created Equal

One of the key issues with polyclonal antibody quality is the purity of the antibody preparation. Polyclonal antibodies are sold in many different preparations including “crude serum” and “purified”. Crude serum has an IgG concentration of about 10 mg/ml, but the concentration of any specific antibody in that pool of IgG is rarely more than […]

Secondary Antibody Issues are Often Overlooked in Immunochemistry

The Choice of Secondary Antibody is one of the Most Overlooked Issues in Immunochemistry. After the tissue of interest has been incubated with the primary antibody, the next critical step involves incubating the tissue in a labeled secondary antibody to detect the presence of the primary antibody. The choice of the secondary antibody has to […]

Are Monoclonal Antibodies Really More Specific?

It is common to see references to the “specificity” or “greater specificity” of monoclonal antibodies compared to polyclonal antibodies. Is that claim justified? No one would dispute the fact that a monoclonal is directed toward a single site or epitope of the target protein, while a polyclonal may contain antibodies directed toward multiple epitopes on […]

Antibody Specificity: The Use of a Blocking Control has only Limited Value

Antibody specificity:  The use of a blocking control has only limited value Antibody specificity is one of the key issues in determining whether you have an antibody that works.  How does one determine that the antibody specifically recognizes only the target of interest?  There are a number of control procedures one can use to be […]