title: Polymer-protein conjugates. II. Affinity precipitation separation of human immunogammaglobulin by a poly(N-isopropylacrylamide)-protein A conjugate.
abstract: The conjugate of protein A with poly(N-isopropylacrylamide) was synthesized and utilized in the separation of human immunogammaglobulin. In the separation process, poly(N-isopropylacrylamide)-protein A conjugate binds to the immunoglobulin with high specificity to form the poly(N-isopropylacrylamide)-protein A/immunoglobulin complex. The complex can be conveniently separated by precipitation upon heating above the lower critical solution temperature of the poly(N-isopropylacrylamide)-protein A/immunogammaglobulin complex. The separation capacity of poly(N-isopropylacrylamide)-protein A conjugate for human immunogammaglobulin was studied and it was demonstrated that approximately one out of every four protein A molecules binds to human immunogammaglobulin with a dissociation constant (Ks) of 3 x 10(-6) M. The affinity precipitation separation of human immunogammaglobulin is a rapid process which avoids the need for chromatographic columns. It can also be designed to run in a continuous mode.
authors.affiliation: Center for Bioengineering, FL-20, University of Washington, Seattle 98195.
authors.forename: J P
authors.initials: JP
authors.lastname: Chen
authors.forename: A S
authors.initials: AS
authors.lastname: Hoffman
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D011232:Chemical Precipitation; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007074:Immunoglobulin G / Q000737:chemistry* / Q000378:metabolism; D013205:Staphylococcal Protein A / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000180:Acrylic Resins; D007074:Immunoglobulin G; D013205:Staphylococcal Protein A; C052970:poly-N-isopropylacrylamide