Magnetic Iron Oxide Nanoparticles Immobilized with Sugar-Containing Poly(ionic liquid) Brushes for Efficient Trapping and Killing of Bacteria.

Poly(ionic liquid)s (PILs) such as polymeric quaternary ammonium compounds (PQACs) are among the most widely used disinfectant agents due to their broad-spectrum antimicrobial activity. However, the high cytotoxicity and difficult reclamation of PQACs remain as challenges for practical water treatment. Herein, we present the synthesis of sugar-incorporated PQACs, which could efficiently decrease the cytotoxicity toward mammalian cells (mouse fibroblast cells, L929). On the basis of the mussel-inspired surface chemistry, the functional glycopolymers could then be immobilized onto the surface of magnetic iron oxide nanoparticles, which are successfully used for the trapping and killing of bacteria. The sugar-containing PILs have combined the lectin-recognition behavior of glycopolymers and the antibacterial activity of PQACs. Antibacterial experiments demonstrate the high-performance of cationic hybrid nanocomposites in killing pathogenic Escherichia coli (E. coli), up to 100% sterilization efficiency. The nanocomposites could be facilely recovered under external magnetic field, and a high sterilization efficiency of 94% could be retained during a five-circulation use. Such hybrid nanocomposites are highly efficient, expediently recyclable, and low-cytotoxicity disinfectant agents and may have potential application for water disinfection treatment.