title: Hybrid materials from intermolecular associations between cationic lipid and polymers.
abstract: Intermolecular associations between a cationic lipid and two model polymers were evaluated from preparation and characterization of hybrid thin films cast on silicon wafers. The novel materials were prepared by spin-coating of a chloroformic solution of lipid and polymer on silicon wafer. Polymers tested for miscibility with the cationic lipid dioctadecyldimethylammonium bromide (DODAB) were polystyrene (PS) and poly(methyl methacrylate) (PMMA). The films thus obtained were characterized by ellipsometry, wettability, optical and atomic force microscopy, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and activity against Escherichia coli. Whereas intermolecular ion-dipole interactions were available for the PMMA-DODAB interacting pair producing smooth PMMA-DODAB films, the absence of such interactions for PS-DODAB films caused lipid segregation, poor film stability (detachment from the silicon wafer) and large rugosity. In addition, the well-established but still remarkable antimicrobial DODAB properties were transferred to the novel hybrid PMMA/DODAB coating, which is demonstrated to be highly effective against E. coli.
authors.affiliation: Instituto de Química, Universidade de São Paulo, CP, Sãu Paulo SP, Brazil.
authors.forename: Edla M A
authors.initials: EM
authors.lastname: Pereira
authors.forename: Priscila M
authors.initials: PM
authors.lastname: Kosaka
authors.forename: Heloísa
authors.initials: H
authors.lastname: Rosa
authors.forename: Débora B
authors.initials: DB
authors.lastname: Vieira
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Kawano
authors.forename: Denise F S
authors.initials: DF
authors.lastname: Petri
authors.forename: Ana M
authors.initials: AM
authors.lastname: Carmona-Ribeiro
mesh_terms: D002152:Calorimetry, Differential Scanning; D002412:Cations / Q000737:chemistry*; D004926:Escherichia coli / Q000166:cytology; D008055:Lipids / Q000737:chemistry*; D050296:Microbial Viability; D018625:Microscopy, Atomic Force; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D002412:Cations; D008055:Lipids; D011137:Polystyrenes; D000644:Quaternary Ammonium Compounds; D014867:Water; C015831:dimethyldioctadecylammonium; D012822:Silicon Dioxide; D019904:Polymethyl Methacrylate