iProtein G Purose 4 Fast Flow combines Purose 4 Fast Flow with the immunoglobulin-binding recombinant protein G ligand, which was removed the albumin binding region of native protein G to improve the purity of purification. Besides, we add more IgG-binding regions to improve the binding capacity of this medium. Recombinant Protein G can be used to purify mammalian monoclonal antibodies and polyclonal antibodies that do not bind well to protein A. Usually protein G has a greater affinity than protein A for most mammalian IgG, especially for the subclass of IgG, such as human IgG3, mouse IgG1 and mouse IgG2a.