title: Antibacterial efficacy of titanium-containing alloy with silver-nanoparticles enriched diamond-like carbon coatings.
abstract: Silver ions (Ag(+)) have strong bactericidal effects and Ag-coated medical devices proved their effectiveness in reducing infections in revision total joint arthroplasty. We quantitatively determined the antimicrobial potency of different surface treatments on a titanium alloy (Ti), which had been conversed to diamond-like carbon (DLC-Ti) and doped with high (Ag:PVP = 1:2) and low (Ag:PVP = 1:10 and 1:20) concentrations of Ag (Ag-DLC-Ti) with a modified technique of ion implantation. Bacterial adhesion and planktonic growth of clinically relevant bacterial strains (Staphylococcus epidermidis, Staphylococcus aureus, and Pseudomonas aeruginosa) on Ag-DLC-Ti were compared to untreated Ti by quantification of colony forming units on the adherent surface and in the growth medium as well as semiquantitatively by determining the grade of biofilm formation by scanning electron microscopy. (1) A significant (p < 0.05) antimicrobial effect could be found for all Ag-DLC-Ti samples (reduced growth by 5.6-2.5 logarithmic levels). (2) The antimicrobial effect was depending on the tested bacterial strain (most for P. aeruginosa, least for S. aureus). (3) Antimicrobial potency was positively correlated with Ag concentrations. (4) Biofilm formation was decreased by Ag-DLC-Ti surfaces. This study revealed potent antibacterial effects of Ag-DLC-Ti. This may serve as a promising novel approach to close the gap in antimicrobial protection of musculoskeletal implants.
authors.affiliation: Clinic of Orthopedics and Sports Orthopedics, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany. norbert.harrasser@mri.tum.de.
authors.forename: Norbert
authors.initials: N
authors.lastname: Harrasser
authors.affiliation: Clinic of Orthopedics and Sports Orthopedics, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany. sebastian.juessen@mri.tum.de.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Jüssen
authors.affiliation: Clinic of Orthopedics and Sports Orthopedics, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany. ingo@banke.eu.
authors.forename: Ingo J
authors.initials: IJ
authors.lastname: Banke
authors.affiliation: Experimental Physics IV, Institut für Physik, Augsburg University, Universitätsstr. 1, 86135, Augsburg, Germany. ralfkmeth@aol.de.
authors.forename: Ralf
authors.initials: R
authors.lastname: Kmeth
authors.affiliation: Clinic of Orthopedics and Sports Orthopedics, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany. eisenhart@tum.de.
authors.forename: Ruediger
authors.initials: R
authors.lastname: von Eisenhart-Rothe
authors.affiliation: Experimental Physics IV, Institut für Physik, Augsburg University, Universitätsstr. 1, 86135, Augsburg, Germany. stritzker@physik.uni-augsburg.de.
authors.forename: Bernd
authors.initials: B
authors.lastname: Stritzker
authors.affiliation: Clinic of Orthopedics and Sports Orthopedics, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany. hans.gollwitzer@mri.tum.de.|ATOS Clinic, Effnerstr.38, 81925, Munich, Germany. hans.gollwitzer@mri.tum.de.
authors.forename: Hans
authors.initials: H
authors.lastname: Gollwitzer
authors.affiliation: Clinic of Orthopedics and Sports Orthopedics, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany. burgkart@tum.de.
authors.forename: Rainer
authors.initials: R
authors.lastname: Burgkart
keywords: Antibacterial coating; Diamond-like carbon; Implant-associated infections; Silver; Titanium