Star Polymers by Cross-Linking of Linear Poly(benzyl-L-glutamate) Macromonomers via Free-Radical and RAFT Polymerization. A Simple Route Toward Peptide-Stabilized Nanoparticles

Poly(benzyl-L-glutamate) (PBLG) macromonomers were synthesized by N-carboxyanhydride (NCA) polymerization initiated with 4-vinyl benzylamine. MALDI-ToF analysis confirmed the presence of styrenic end-groups in the PBLG. Free-radical and RAFT polymerization of the macromonomer in the presence of divinyl benzene produced star polymers of various molecular weights, polydispersity, and yield depending on the reaction conditions applied. The highest molecular weight (M-w) of 10,170,000 g/mol was obtained in a free-radical multi-batch approach. It was shown that the PBLG star polymers can be deprotected to obtain poly(glutamic acid) star polymers, which form water soluble pH responsive nanoparticles. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4602-4610, 2010