title: DLC coatings for UHMWPE: relationship between bacterial adherence and surface properties.
abstract: Development of intrinsically antibacterial surfaces is of key importance in the context of prostheses used in orthopedic surgery. This work presents a thorough study of several plasma-based coatings that may be used with this functionality: diamond-like carbon (DLC), fluorine-doped DLC (F-DLC), and a high-fluorine-content-carbon-fluor polymer (CF(X)). The coatings were obtained by a radio-frequency plasma-assisted deposition on ultra high molecular weight polyethylene (UHMWPE) samples and physicochemical properties of the coated surfaces were correlated with their antibacterial performance against collection and clinical Staphylococcus aureus and Staphylococcus epidermidis strains. The fluorine content and the relative amount of C-C and C-F bonds were controlled by X-ray photoelectron spectroscopy, and hydrophobicity and surface tension by contact angle measurements. Surface roughness was studied by Atomic Force Microscopy. Additional nanoidentation studies were performed for DLC and F-DLC coatings. Unpaired t test and regression linear models evaluated the adherence of S. aureus and S. epidermidis on raw and coated UHMWPE samples. Comparing with UHMWPE, DLC/UHMWPE was the least adherent surface with independence of the bacterial species, finding significant reductions (p ≤ 0.001) for nine staphylococci strains. Bacterial adherence was also significantly reduced in F-DLC/ UHMWPE and CFx/UHMWPE for six strains.
authors.affiliation: Departamento of Clinical Microbiology, IIS-Fundación Jiménez-Díaz, Madrid, Spain.
authors.forename: G
authors.initials: G
authors.lastname: Del Prado
authors.forename: A
authors.initials: A
authors.lastname: Terriza
authors.forename: A
authors.initials: A
authors.lastname: Ortiz-Pérez
authors.forename: D
authors.initials: D
authors.lastname: Molina-Manso
authors.forename: I
authors.initials: I
authors.lastname: Mahillo
authors.forename: F
authors.initials: F
authors.lastname: Yubero
authors.forename: J A
authors.initials: JA
authors.lastname: Puértolas
authors.forename: M
authors.initials: M
authors.lastname: Manrubia-Cobo
authors.forename: E
authors.initials: E
authors.lastname: Gómez Barrena
authors.forename: J
authors.initials: J
authors.lastname: Esteban
mesh_terms: D001422:Bacterial Adhesion / Q000187:drug effects*; D020099:Coated Materials, Biocompatible / Q000494:pharmacology*; D018130:Diamond / Q000494:pharmacology*; D055119:Elastic Modulus / Q000187:drug effects; D006244:Hardness / Q000187:drug effects; D006847:Hydrocarbons, Iodinated / Q000737:chemistry; D008826:Microbial Sensitivity Tests; D018625:Microscopy, Atomic Force; D036103:Nanotechnology; D056951:Photoelectron Spectroscopy; D011095:Polyethylenes / Q000737:chemistry*; D012044:Regression Analysis; D013211:Staphylococcus aureus / Q000166:cytology* / Q000187:drug effects; D013212:Staphylococcus epidermidis / Q000166:cytology* / Q000187:drug effects; D013500:Surface Tension / Q000187:drug effects; D017155:Wettability / Q000187:drug effects
chemical_list: D020099:Coated Materials, Biocompatible; D006847:Hydrocarbons, Iodinated; D011095:Polyethylenes; C111601:ultra-high molecular weight polyethylene; C027946:methylene iodide; D018130:Diamond