Selective and Tunable Galectin Binding of GlycopolymersSynthesized by a Generalizable Conjugation Method

Glycopolymers, conjugates of synthetic polymers with pendant carbohydrates, are becoming increasingly important to probe the role of carbohydrates in cellular processes and for applications like biosensors and drug delivery. A library of glycopolymers bearing different sugar moieties was synthesized by grafting amino-functionalized sugars to poly(acrylic acid) via DMTMM coupling. Primary amines were introduced at the anomeric (C-1) position to a number of unprotected mono- di- and tri-saccharides using ammonium carbamate, and conjugated to poly(acrylic acid) of different molecular weights, synthesized by reversible addition fragmentation chain transfer (RAFT) polymerization. This approach provides a simple and efficient route for the preparation of glycopolymers that differ only in the identity or degree of substitution of the sugar moiety on the polymer. The binding parameters (ka, kd, KD) of these new glycopolymers to galectins-1 and -3 were quantified using surface plasmon resonance. The galectins sele...