Purification of antibody fragments

Several improvements have been made in the past few years to simplify the expression and purification of antibody fragments in bacteria. These include the development of improved vectors with strong promoters... 

For small-scale purification, mix 5—10 mL of antibody fragments with 100-200 pL of pre-swollen protein A-Sepharose. Purify using ultrafree-MC filters following the above protocol, but wash with 1 mL of buffer, and elute with 100 pL of eluant... 

Fortunately the following advances permitted the development of noncompetitive methods for intact PTH (1) the determination of the amino acid sequence of human (h)PTH (2) increased understanding of the secretion, metabolism, clearance, and circulating forms of PTH and (3) the synthesis of hPTH, fragments of hPTH, and analogues of fragments for use as immunogens, tracers, and cahbrators, for characterization of antiserum and antibody specificity, and for affinity purification of antibodies. 

CHAPTER 35, FIGURE 10 Binding of protein G (S. aureus) to an Fc fragment. Protein G binding mimics the Fc receptor binding of an Ig in the Ig Fc region. Protein G is used for purification of antibodies and in their capture in immunoassays. The figure is derived from the coordinates published in the Protein Data Bank file IFCC. 

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