Synthesis and noncovalent protein conjugation of linear-hyperbranched PEG-poly(glycerol) α,ω_n-telechelics

(Figure Presented) Linear-hyperbranched, heterobifunctional α,ω_n telechelic block copolymers consisting of a linear poly(ethylene glycol) (PEG) chain and a hyperbranched polyglycerol (PG) block have been prepared in five steps, using a protected amino-functional initiator. The polyfunctionality ω_n (OH groups) can be adjusted by the degree of polymerization (DP_n) of the polyglycerol block. Subsequent introduction of a single biotin unit by amidation in α-position permitted noncovalent bioconjugation with avidin.