title: Antibacterial properties of Ag (or Pt)-containing calcium phosphate coatings formed by micro-arc oxidation.
abstract: Silver (or platinum)-containing calcium phosphate (hydroxyapatite (HA) and tricalcium phosphate (alpha-TCP)) coatings on titanium substrates were formed by micro-arc oxidation (MAO) and their in vitro antibacterial activity and in vitro cytotoxicity were evaluated. MAO was performed in an electrolytic solution containing beta-glycerophosphate disodium salt pentahydrate (beta-GP) and calcium acetate monohydrate (CA), and Ag and Pt were introduced in the form of AgNO(3) (or CH(3)COOAg) and H(2)PtCl(6), respectively. The MG63 and human osteosarcoma (HOS) cell lines were used to investigate the proliferation and differentiation behavior of the cells, respectively, whereas two strains of bacteria, Staphylococcus aureus and Escherichia coli, were used to evaluate the antibacterial activity of the coatings. The phase, morphology, and Ag content of the coatings were strongly dependent on the applied voltage and Ag precursor concentration. HA and alpha-TCP phases were detected in the coatings oxidized above 400 V and the presence of Ag was confirmed by EDS. While the coatings with a high content of Ag were cytotoxic and those obtained in the Pt-containing electrolyte had no apparent antibacterial activity, the calcium phosphate coatings obtained in the low Ag concentration electrolyte exhibited in vitro antibacterial activity but no cytotoxicity. Thus, biocompatible calcium phosphate coatings on Ti implants with antibacterial activity can be achieved by one-step MAO.
authors.affiliation: Department of Materials Science and Engineering, Seoul National University, Seoul 151-742, South Korea.
authors.forename: Won-Hoon
authors.initials: WH
authors.lastname: Song
authors.forename: Hyun Sam
authors.initials: HS
authors.lastname: Ryu
authors.forename: Seong-Hyeon
authors.initials: SH
authors.lastname: Hong
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000737:chemistry*; D002130:Calcium Phosphates; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000737:chemistry* / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects; D006801:Humans; D012516:Osteosarcoma / Q000473:pathology; D010984:Platinum; D012834:Silver; D013211:Staphylococcus aureus / Q000187:drug effects; D014025:Titanium
chemical_list: D000900:Anti-Bacterial Agents; D002130:Calcium Phosphates; D020099:Coated Materials, Biocompatible; D012834:Silver; D010984:Platinum; D014025:Titanium