Stimuli-Responsive Polymer-Antibody Conjugates via RAFT and Tetrafluorophenyl Active Ester Chemistry

Highly efficient polymer-antibody conjugations were demonstrated via a tetrafluorophenyl active ester. A well-defined diblock copolymer was synthesized by reversible addition–fragmentation chain transfer (RAFT) polymerization with a temperature-responsive block, poly(N-isopropylacrylamide), and a block of N,N-dimethylacrylamide and 2,3,5,6-tetrafluorophenyl acrylate active ester. The polymer was conjugated to anti-p24 IgG antibody with about 100% efficiency in as little as 2 h at room temperature in a pH 10.8 buffer. The temperature-responsiveness of the polymer was conferred to the polymer–antibody conjugates after conjugation. The conjugates bound p24 antigen specifically and with binding efficiency comparable to native antibodies. Thus, the active ester diblock copolymer can facilitate the synthesis of temperature-responsive bioconjugates, which may be promising reagents for immunoassays, bioseparations, and specimen-enrichment applications.