What is the difference between an IgG purification and an affinity purification?
• An IgG purification isolates all IgG in the serum, regardless of the specificity. This is advantageous for applications where removing serum proteins will help reduce background noise, but affinity purification against the immunizing protein isn’t possible. The affinity purification, by contrast, is advantageous for isolating only those antibodies that recognize a specific epitope. With a peptide, this can yield antibodies that have the same specificity as monoclonal antibodies.