title: Biofilm inhibition and drug-eluting properties of novel DMAEMA-modified polyethylene and silicone rubber surfaces.
abstract: Poly(2-(dimethylaminoethyl) methacrylate) (pDMAEMA) was grafted to low density polyethylene (LDPE) and silicone rubber (SR) in order to make them less susceptible to microbial biofilm formation. The direct grafting of DMAEMA using γ-rays was an efficient and fast procedure for obtaining modified materials, which could be quaternized in a second step using methyl iodide. Raman spectroscopy showed that the grafting occurred only at the surface of the LDPE, but both at the surface and in the bulk of the SR. Consequently, the grafted chains caused changes in the surface-related features of the LDPE (water contact angle and viscoelastic behavior in the dry state) and in the bulk-related properties of the SR (swelling and viscoelasticity in the swollen state). The microbiological assays revealed that the grafted DMAEMA reduced Candida albicans biofilm formation (almost no biofilm on SR), while the quaternized surfaces inhibited C. albicans and Staphylococcus aureus biofilm by more than 99% compared to pristine materials. Modified LDPE and SR were capable of holding considerable amounts of nalidixic acid, an anionic antimicrobial drug, and sustained the release for several hours. In addition, the grafted materials were cytocompatible (fibroblast cell survival > 70%). In conclusion, these materials have the ability to inhibit microbial biofilm formation and at the same time act as drug-eluting systems, and for that reason may hold great promise for anti-biofouling applications.
authors.affiliation: Departamento de Quimica de Radiaciones y Radioquimica, Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, Mexico, Mexico.
authors.forename: Angel
authors.initials: A
authors.lastname: Contreras-García
authors.forename: Emilio
authors.initials: E
authors.lastname: Bucio
authors.forename: Gilles
authors.initials: G
authors.lastname: Brackman
authors.forename: Tom
authors.initials: T
authors.lastname: Coenye
authors.forename: Angel
authors.initials: A
authors.lastname: Concheiro
authors.forename: Carmen
authors.initials: C
authors.lastname: Alvarez-Lorenzo
mesh_terms: D018407:Bacterial Physiological Phenomena; D001672:Biocompatible Materials; D018441:Biofilms / Q000187:drug effects*; D057219:Biofouling / Q000517:prevention & control*; D002176:Candida albicans / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D008689:Methacrylates / Q000494:pharmacology*; D009268:Nalidixic Acid / Q000627:therapeutic use*; D009757:Nylons / Q000494:pharmacology*; D020959:Polyethylene; D012826:Silicone Elastomers / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D013499:Surface Properties
chemical_list: D001672:Biocompatible Materials; D008689:Methacrylates; D009757:Nylons; D012826:Silicone Elastomers; C407037:poly(2-(dimethylamino)ethyl methacrylate); D009268:Nalidixic Acid; D020959:Polyethylene