Glycopolymer-coated iron oxide nanoparticles: shape-controlled synthesis and cellular uptake

Carbohydrates are involved in different cellular recognition events, and glycopolymers with carbohydrate side chains are currently being applied in many fields, with much potential for disease treatment. The aggregation shape has obvious effects on the nanoparticle-cell interaction and is therefore important for the applications of glycopolymers in biological systems. The synthesis of well-defined glyco-nanoparticles, especially non-spherical ones, is challenging work. Herein, iron oxide nanoparticles with different shapes (spindle and cubic-like) were first obtained and used as a core that was coated with dopamine methacrylamide (DMA) via catecholic chemistry for the introduction of vinyl groups. RAFT-synthesized glycopolymers were then conjugated to the DMA-coated iron oxide nanoparticles via a thiol-ene coupling reaction. By combining the convenience of inorganic nanoparticle shape control, biomimic catecholic chemistry, and efficient thiol-ene reaction, glycopolymer-decorated nanoparticles were easily obtained. Glyco-nanoparticles with variable shapes are stable in serum and exhibit shape-dependent cell uptake behaviors as well as enhanced activity toward specific lectins. The fabrication of biologically active non-spherical nanoparticles will be beneficial for both fundamental research on nanoparticle-cell interaction and related applications for disease treatment.