rProtein A Sepharose(R) 4 Fast Flow is a well established antibody affinity medium designed for the purification of monoclonal and polyclonal antibodies at both laboratory and process scale.rProtein A Sepharose(R) 4 Fast Flow is based on the well established Sepharose(R) Fast Flow platform and is used in many approved monoclonal antibody (MAb) processes. It is composed of recombinant protein A coupled to the cross-linked 4% agarose base matrix. The recombinant protein A is produced in E. coli and has been specially engineered to favour an oriented coupling giving a matrix with enhanced binding capacity. The epoxy based coupling ensures low ligand leakage. The specificity of the recombinant protein A for the Fc region of IgG is similar to native protein A giving a high purification factor in a single step. The high capacity low ligand leakage and a well established base matrix makes rProtein A Sepharose(R) 4 Fast Flow suitable for purification of monoclonal antibodies at both laborat