Synthesis of Heterotelechelic Polymers for Conjugation of Two Different Proteins.
In this report we describe a straightforward approach to synthesize polymers with end-groups that bind site-specifically to two different proteins. Telechelic biotin, maleimide poly(N-isopropylacrylamide) (pNIPAAm) was synthesized for the formation of streptavidin (SAv)-bovine serum albumin (BSA) polymer conjugates. Reversible addition-fragmentation chain transfer (RAFT) polymerization of NIPAAm was conducted in the presence of biotinylated chain transfer agents (CTAs) with either ester or amide linkages, and the resultant α-biotinylated pNIPAAm were formed with low polydispersity indices (PDI ≤ 1.09). UV-Vis analysis of the trithiocarbonate chain-ends indicated 88% or greater retention of the group. A maleimide was introduced to the ω chain-end via a radical cross-coupling reaction with a functionalized azo-initiator. The polymer structures were characterized by1H NMR spectroscopy and gel permeation chromatography (GPC). The resultant biotin-maleimide heterotelechelic polymer was used to form a SAv-BSA heterodimer conjugate. Bioconjugate formation was confirmed by gel electrophoresis.
Department of Chemistry and Biochemistry and the California NanoSystems Institute University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, CA 90095-1569.
Karina L
KL
Heredia
Department of Chemistry and Biochemistry and the California NanoSystems Institute University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, CA 90095-1569.
Gregory N
GN
Grover
Department of Chemistry and Biochemistry and the California NanoSystems Institute University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, CA 90095-1569.
Lei
L
Tao
Department of Chemistry and Biochemistry and the California NanoSystems Institute University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, CA 90095-1569.
Heather D
HD
Maynard