PEG-polypeptide dual brush block copolymers: Synthesis and application in nanoparticle surface PEGylation

Amphiphilic polypeptide-containing hybrid dual brush block copolymers with controlled molecular weights and narrow molecular weight distributions were synthesized in one pot via ring-opening metathesis polymerization of sequentially added norbornyl-PEG and N-(2-((trimethylsilyl)amino)ethyl)-5- norbornene-endo-2,3-dicarboximide (M1), followed by ring-opening polymerization of amino acid N-carboxyanhydrides. Polylactide nanoparticles coated with these amphiphilic dual brush block copolymers showed significantly improved stability in PBS solution compared to those coated with amphiphilic linear block copolymers such as PEG-polylactide and PEG-polypeptides.