title: Cationic polycarbonate-grafted superparamagnetic nanoparticles with synergistic dual-modality antimicrobial activity.
abstract: We report a new class of antimicrobial nanomaterials with biodegradable cationic polycarbonates grafted on superparamagnetic nanoparticles. Our results have shown that end-functionalized cationic polycarbonates, synthesized by organocatalytic ring opening polymerization, can be grafted onto superparamagnetic MnFe2O4 nanoparticles via ligand exchange. In comparison with the individual building blocks, the core-shell hybrid nanoparticles led to improved antimicrobial activities in two ways: first, the cationic polycarbonates in a brush form afforded a greater charge density than that of free polymer chains, resulting in stronger interactions with bacterial surfaces. Second, the structural integration of the "soft" polycarbonate shell and the "hard" superparamagnetic core in the hybrid nanoparticles brings about a synergistic action of membrane disruption by the cationic shell and magnetic hyperthermia by the nanoparticle core. The combination of two physical killing mechanisms holds great promise in fighting against a broad spectrum of bacterial pathogens.
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University, 70 Nanyang Drive, Singapore 637457. hduan@ntu.edu.sg mbechan@ntu.edu.sg.
authors.forename: Lu
authors.initials: L
authors.lastname: Pu
authors.forename: Jinbao
authors.initials: J
authors.lastname: Xu
authors.forename: Yimin
authors.initials: Y
authors.lastname: Sun
authors.forename: Zheng
authors.initials: Z
authors.lastname: Fang
authors.forename: Mary B
authors.initials: MB
authors.lastname: Chan-Park
authors.forename: Hongwei
authors.initials: H
authors.lastname: Duan
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry*; D002412:Cations / Q000737:chemistry; D004912:Erythrocytes / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D005290:Ferric Compounds / Q000737:chemistry*; D006461:Hemolysis; D006801:Humans; D020128:Inhibitory Concentration 50; D008280:Magnetics; D017895:Manganese Compounds / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry; D010316:Particle Size; D011076:Polycarboxylate Cement / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000187:drug effects; D013499:Surface Properties; D013696:Temperature
chemical_list: D000890:Anti-Infective Agents; D002412:Cations; D005290:Ferric Compounds; D017895:Manganese Compounds; D011076:Polycarboxylate Cement; C551151:manganese ferrite; C005506:polycarbonate