[In vitro comparison of antibacterial properties of plasma sprayed wollastonite coatings loading silver and gentamicin].
OBJECTIVE
To develop antibacterial coatings for orthopedic implants with a sustained release of drugs.


METHODS
Wollastonite coatings were deposited on the titanium substrates by an atmospheric plasma spray system. After soaking in weight percent of 5% AgNO(3) solution for 24 h, the wollastonite coatings loading silver were obtained. Gentamicin were loaded on the wollastonite coatings by collagen grafting process. The release rates of drugs from wollastonite coatings were investigated by the in vitro solution soaking test. One strain of S. aureus was used in zone of inhibition test to evaluate the antibacterial properties of drug loaded wollastonite coatings, and the cell culture test was used to evaluate their cytotoxicity.


RESULTS
Silver and gentamicin loaded wollastonite coatings were successfully prepared. The release of silver ions from the silver loaded wollastonite coatings lasted 50 d in deionized water, effectively inhibiting the growth of S. aureus for 40 d. While an initial burst release of gentamicin was found during the in vitro solution soaking test. The gentamicin released from gentamicin loaded wollastonite coatings can inhibit the growth of S. aureus for 18 d. Both the two kinds of antibacterial wollastonite coatings showed no adverse effect on cellular adhesion, proliferation and alkaline phosphatase expression.


CONCLUSIONS
Compared with gentamicin loaded wollastonite coatings, silver loaded wollastonite coatings may have more promising clinical applications due to the even and long-time antibacterial agent release.
Dong
Yu-qi
YQ
Department of Orthopedics, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200127, China.
Li
Bao-e
BE
Liu
Xuan-yong
XY
Feng
Yu
Y
Cao
Cong
C
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D017610:Calcium Compounds; D002478:Cells, Cultured; D020099:Coated Materials, Biocompatible / Q000494:pharmacology*; D005839:Gentamicins / Q000494:pharmacology*; D008422:Materials Testing; D008826:Microbial Sensitivity Tests; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects; D017640:Silicates; D012834:Silver / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D017610:Calcium Compounds; D020099:Coated Materials, Biocompatible; D005839:Gentamicins; D017640:Silicates; D012834:Silver; C031293:calcium silicate