title: [Experimental research in vitro on antibacterial property and biocompatibility of silver-containing hydroxyapatite coating].
abstract: OBJECTIVE
  To prepare silver-containing hydroxyapatite coating (hydroxyapatite/Ag, HA/Ag) and investigate its antibacterial property and biocompatibility in vitro.
  
  
  METHODS
  Vacuum plasma spraying technique was adopted to prepare HA/Ag coating on titanium alloy substrate (3% Ag). After incubating the HA/Ag and the HA coating under staphylococcus aureus and pseudomonas aeruginosa suspensions of 2% tryptic soy broth (TBS) medium for 2, 4 and 7 days, respectively, the biofilm on the coatings was examined by confocal laser scanning microscope, and the bacterial density and viable bacterial percentage of bacterial biofilm were calculated. Meanwhile, the micro-morphology of bacterial biofilm was observed by SEM, the cytotoxicity was detected via MTT and the biocompatibility of biofilm was evaluated by acute haemolysis test.
  
  
  RESULTS
  Compared with HA coating, the bacterial biofilm's thickness on the surface of HA/Ag coating witnessed no significant difference at 2 days after culture (P > 0.05), but decreased obviously at 4 and 7 days after culture (P < 0.01). The bacterial density of the biofilm increased with time, but there was no significant difference between two coatings (P > 0.05) at 2, and 7 days after culture. The viable bacterial percentage of the biofilms on the surface of HA/Ag coating decreased obviously compared with that of HA coating at 2, 4 and 7 days after culture (P < 0.01). The MTT notified the cytotoxic grade of both coatings was zero. The acute haemolysis assay showed that the hemolytic rate of HA/Ag and HA coating was 0.19% and 0.12%, respectively.
  
  
  CONCLUSIONS
  With good biocompatibility, significant antibacterial property against staphylococcus aureus and pseudomonas aeruginosa, no obvious cytotoxicity and no erythrocyte destruction, the vacuum plasma sprayed HA/Ag coating is a promising candidate for the surface of orthopedic metal implants to improve their osseointegration and antibacterial property.
authors.affiliation: Department of Orthopaedics, the Sixth People's Hospital, Shanghai Jiaotong University, Shanghai, 200233, P.R. China.
authors.forename: Hongjiang
authors.initials: H
authors.lastname: Ruan
authors.forename: Junjian
authors.initials: J
authors.lastname: Liu
authors.forename: Cunyi
authors.initials: C
authors.lastname: Fan
authors.forename: Xuebin
authors.initials: X
authors.lastname: Zheng
authors.forename: Yikai
authors.initials: Y
authors.lastname: Chen
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology*; D001672:Biocompatible Materials; D018441:Biofilms / Q000187:drug effects; D054855:Drug-Eluting Stents; D017886:Durapatite / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D008422:Materials Testing; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D012834:Silver; D013211:Staphylococcus aureus / Q000187:drug effects; D013242:Sterilization / Q000295:instrumentation*
chemical_list: D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; D012834:Silver; D017886:Durapatite