Some studies show that various enzymes can be attached to antibodies and proteins using different coupling chemistries, among which the most common enzymes are horseradish peroxidase (HRP) and alkaline phosphatase (AP). Antibody-enzyme conjugates are the most extensive application of antibody conjugation. The conjugation of enzymes to antibodies is the formation of a stable, covalent linkage between an antigen-specific monoclonal or polyclonal antibody and enzyme. antibody polymer conjugation https://www.solutions.bocsci.com/antibody-enzyme-conjugate.htm