Synthesis and properties of novel biomimetic and thermo-responsive dextran-based biohybrids.

A new class of biodegradable, biomimetic and thermo-responsive dextran/synthetic glycopolymer biohybrids (dextran-graft-poly(lactobionamidoethyl methacrylate)-block-poly(di(ethylene glycol) methyl ether methacrylate), dextran-g-(PLAMA-b-PDEGMA)), was synthesized by the direct atom transfer radical polymerization (ATRP) of unprotected lactobionamidoethyl methacrylate (LAMA) glycomonomer and di(ethylene glycol) methyl ether methacrylate (DEGMA) monomer. The dextran macroinitiator for ATRP was prepared by partial esterification of the hydroxyl groups of the polysaccharide with 2-bromo-2-methylpropionic acid (BrMPA). The biohybrids containing PDEGMA segments exhibited a lower critical solution temperature (LCST) behavior, which changed from unimers to aggregates in solutions. Moreover, it was demonstrated that these biohybrids had specific biomolecular recognition with ricinus communis agglutinin 120 (RCA₁₂₀) in comparison with bovine serum albumin (BSA). Furthermore, these biohybrids showed good biocompatibility in the cytotoxicity assays. This hopefully provides a platform for targeted drug delivery and studying the biomolecular recognition between sugar and lectin.