title: Self-Sterilizing, Self-Cleaning Mixed Polymeric Multifunctional Antimicrobial Surfaces.
abstract: Mitigation of bacterial adhesion and subsequent biofilm formation is quickly becoming a strategy for the prevention of hospital-acquired infections. We demonstrate a basic strategy for surface modification that combines the ability to control attachment by microbes with the ability to inactivate microbes. The surface consists of two active materials: poly(p-phenylene ethynylene)-based polymers, which can inactivate a wide range of microbes and pathogens, and poly(N-isopropylacrylamide)-based polymers, which can switch between an hydrophobic "capture" state and a hydrophilic "release" state. The combination of these materials creates a surface that can both bind microbes in a switchable way and kill surface-bound microbes efficiently. Considerable earlier work with cationic poly(p-phenylene ethynylene) polyelectrolytes has demonstrated and characterized their antimicrobial properties, including the ability to efficiently destroy or deactivate Gram-negative and Gram-positive bacteria, fungi, and viruses. Similarly, much work has shown (1) that surface-polymerized films of poly(N-isopropylacrylamide) are able to switch their surface thermodynamic properties from a swollen, relatively hydrophilic state at low temperature to a condensed, relatively hydrophobic state at higher temperature, and (2) that this switch can control the binding and/or release of microbes to poly(N-isopropylacrylamide) surfaces. The active surfaces described herein were fabricated by first creating a film of biocidal poly(p-phenylene ethynylene) using layer-by-layer methods, and then conferring switchable adhesion by growing poly(N-isopropylacrylamide) through the poly(p-phenylene ethynylene) layer, using surface-attached polymerization initiators. The resulting multifunctional, complex films were then characterized both physically and functionally. We demonstrate that such films kill and subsequently induce widespread release of Gram-negative and Gram-positive bacteria.
authors.affiliation: Department of Nanoscience and Microsystems Engineering, University of New Mexico , Albuquerque, New Mexico 87131-1341, United States.|Center for Biomedical Engineering, Department of Chemical and Biological Engineering, University of New Mexico , Albuquerque, New Mexico 87131-1341, United States.
authors.forename: Harry C
authors.initials: HC
authors.lastname: Pappas
authors.affiliation: Department of Chemistry, University of Florida , Gainesville, Florida 32611, United States.
authors.forename: Samantha
authors.initials: S
authors.lastname: Phan
authors.affiliation: Department of Chemistry, University of New Mexico , Albuquerque, New Mexico 87131-1341, United States.
authors.forename: Suhyun
authors.initials: S
authors.lastname: Yoon
authors.affiliation: Department of Chemistry, University of New Mexico , Albuquerque, New Mexico 87131-1341, United States.
authors.forename: Lance E
authors.initials: LE
authors.lastname: Edens
authors.affiliation: Department of Chemistry, University of Florida , Gainesville, Florida 32611, United States.
authors.forename: Xiangli
authors.initials: X
authors.lastname: Meng
authors.affiliation: Department of Chemistry, University of Florida , Gainesville, Florida 32611, United States.
authors.forename: Kirk S
authors.initials: KS
authors.lastname: Schanze
authors.affiliation: Center for Biomedical Engineering, Department of Chemical and Biological Engineering, University of New Mexico , Albuquerque, New Mexico 87131-1341, United States.
authors.forename: David G
authors.initials: DG
authors.lastname: Whitten
authors.affiliation: Department of Chemistry, University of New Mexico , Albuquerque, New Mexico 87131-1341, United States.
authors.forename: David J
authors.initials: DJ
authors.lastname: Keller
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects* / Q000254:growth & development / Q000472:pathogenicity; D001422:Bacterial Adhesion / Q000187:drug effects; D018441:Biofilms / Q000187:drug effects*; D003428:Cross Infection / Q000188:drug therapy* / Q000382:microbiology; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D011108:Polymers / Q000737:chemistry / Q000494:pharmacology*; D013499:Surface Properties
chemical_list: D000890:Anti-Infective Agents; D011108:Polymers
keywords: PNIPAAm; bacteria; conjugated polyelectrolyte; kill; release