title: Thin magnesium layer confirmed as an antibacterial and biocompatible implant coating in a co‑culture model.
abstract: Implant-associated infections commonly result from biofilm‑forming bacteria and present severe complications in total joint arthroplasty. Therefore, there is a requirement for the development of biocompatible implant surfaces that prevent bacterial biofilm formation. The present study coated titanium samples with a thin, rapidly corroding layer of magnesium, which were subsequently investigated with respect to their antibacterial and cytotoxic surface properties using a Staphylococcus epidermidis (S. epidermidis) and human osteoblast (hOB) co‑culture model. Primary hOBs and S. epidermidis were co‑cultured on cylindrical titanium samples (Ti6Al4V) coated with pure magnesium via magnetron sputtering (5 µm thickness) for 7 days. Uncoated titanium test samples served as controls. Vital hOBs were identified by trypan blue staining at days 2 and 7. Planktonic S. epidermidis were quantified by counting the number of colony forming units (CFU). The quantification of biofilm‑bound S. epidermidis on the surfaces of test samples was performed by ultrasonic treatment and CFU counting at days 2 and 7. The number of planktonic and biofilm‑bound S. epidermidis on the magnesium‑coated samples decreased by four orders of magnitude when compared with the titanium control following 7 days of co‑culture. The number of vital hOBs on the magnesium‑coated samples was observed to increase (40,000 cells/ml) when compared with the controls (20,000 cells/ml). The results of the present study indicate that rapidly corroding magnesium‑coated titanium may be a viable coating material that possesses antibacterial and biocompatible properties. A co‑culture test is more rigorous than a monoculture study, as it accounts for confounding effects and assesses additional interactions that are more representative of in vivo situations. These results provide a foundation for the future testing of this type of surface in animals.
authors.affiliation: Biomechanics and Implant Technology Research Laboratory, Department of Orthopaedics, University Medicine Rostock, D‑18057 Rostock, Germany.
authors.forename: Sarah
authors.initials: S
authors.lastname: Zaatreh
authors.affiliation: Institute for Materials Science, Faculty of Engineering, University of Kiel, D‑24143 Kiel, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Haffner
authors.affiliation: Biomechanics and Implant Technology Research Laboratory, Department of Orthopaedics, University Medicine Rostock, D‑18057 Rostock, Germany.
authors.forename: Madlen
authors.initials: M
authors.lastname: Strauss
authors.affiliation: Biomechanics and Implant Technology Research Laboratory, Department of Orthopaedics, University Medicine Rostock, D‑18057 Rostock, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Dauben
authors.affiliation: Institute for Materials Science, Faculty of Engineering, University of Kiel, D‑24143 Kiel, Germany.
authors.forename: Christiane
authors.initials: C
authors.lastname: Zamponi
authors.affiliation: Biomechanics and Implant Technology Research Laboratory, Department of Orthopaedics, University Medicine Rostock, D‑18057 Rostock, Germany.
authors.forename: Wolfram
authors.initials: W
authors.lastname: Mittelmeier
authors.affiliation: Institute for Materials Science, Faculty of Engineering, University of Kiel, D‑24143 Kiel, Germany.
authors.forename: Eckhard
authors.initials: E
authors.lastname: Quandt
authors.affiliation: Institute of Medical Microbiology, Virology and Hygiene, University Medicine Rostock, D‑18057 Rostock, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Kreikemeyer
authors.affiliation: Biomechanics and Implant Technology Research Laboratory, Department of Orthopaedics, University Medicine Rostock, D‑18057 Rostock, Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Bader
mesh_terms: D000368:Aged; D000497:Alloys; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000494:pharmacology*; D018920:Coculture Techniques / Q000379:methods*; D003470:Culture Media / Q000737:chemistry; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007477:Ions; D008274:Magnesium / Q000494:pharmacology*; D008297:Male; D008954:Models, Biological; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects / Q000648:ultrastructure; D010933:Plankton / Q000187:drug effects; D019736:Prostheses and Implants; D013212:Staphylococcus epidermidis / Q000166:cytology / Q000187:drug effects / Q000648:ultrastructure; D014025:Titanium / Q000494:pharmacology
chemical_list: D000497:Alloys; D000900:Anti-Bacterial Agents; D020099:Coated Materials, Biocompatible; D003470:Culture Media; D007477:Ions; C031462:titanium alloy (TiAl6V4); D014025:Titanium; D008274:Magnesium