F(ab')₂

F(ab') 2 fragments of antibodies are generated by pepsin digestion of whole IgG antibodies to remove most of the Fc region while leaving intact some of the hinge region. F(ab')2 fragments have two antigen-binding Fab portions linked together by disulfide bonds, and therefore are divalent (Figure 1). The average molecular weight is about 110 kDa. They are used for specific applications, such as to avoid binding of antibodies to live cells with Fc receptors or to Protein A or Protein G.