Our secondary antibodies are prepared by hyper-immunizing animals in a manner that produces high-affinity antibodies. These are then purified by an affinity chromatography procedure designed to remove any low-affinity antibodies. Cross-reactivities that can interfere with specific labeling are removed by solid-phase adsorption techniques. The final product is then subjected to phase binding assays and IHC tissue staining. These unconjugated antibodies are used to generated our other secondary antibody conjugates.