Synthesis and peptide functionalization of hyperbranched poly(arylene oxindole) towards versatile biomaterials

Abstract

Hyperbranched polymers (HBPs) are dendritic macromolecules with a three-dimensional globular nanostructure. Due to their unique properties, HBPs are interesting for biomedical applications such as drug/protein delivery and tissue engineering, and functionalized HBPs can be tailored to exhibit specific biological responses. Superelectrophilic arylation of isatin is one strategy to synthesize hydrophobic hyperbranched poly(arylene oxindole)s from A₂ and B₃ monomers in one step. Herein, an azide derivative of this HBP, which allows postgrafting with a cell adhesive RGD peptide derivative via copper assisted azide–alkyne cycloaddition (CuAAC), is prepared. The resulting materials are shown to be cytocompatible and support cell attachment and proliferation; moreover, the amount of postgrafted peptide can be controlled. Overall, the demonstrated postgrafting strategy is compatible with different biomolecules, and the functionalized HBPs show high potential as biomaterials.