Production of nano silver coated hydroxyapatite and antibacterial surface applications

The use of antibacterial products in the field of biomedical implants and many other industrial areas has increeased in recent years. The selection of suitable antibacterial agents and the processing method is important step in commercial applications. Due to the possible antibacterial ressistance of common microorganisms against the organic antibiotics, the nano metal based antimicrobial products provide an alternative method. The utilization of the antibacterial products in commonly used public areas is important in order to reduce the growth of the bacteria on the surface of the contaminated objects and to prevent the spread of the microorganisms in human body. In our study, the possible use of nano silver in orthopedic implants as an antimicrobial material has been investigated. Ti based plates were used as the substrate. The Ti surfaces were coated by previously prepared special nano Ag-HAP particles using the plasma sprey method. The hydroxyapatite (HAP) coatings were applied to the orthopedic implant surfaces to enhance the cell growth and the osseointegration property. In some cases, the bacterial contamination of the implant can cause infections in patients body and may result in serious health problems. In order to provide a sterile implant surface, HAP particles coated by nano silver as the antibacterial material were deposited to the Ti implant surfaces. The nano Ag-HAP particles were prepared using the electroless deposition method. In this method, the HAP particles were dispersed in acetone containing the Ag+ ions and then the addition of poly(dimethylsiloxane) (PDMS) to the mixture with continuous stirring. This procedure yielded a powder of 0-40 nm silver coated nano Ag-HAP (% 0,24 Ag) powder. The prepared particles were coated to the Ti plate surfaces by the plasma sprey and the obtained coatings were heat treated at 700 ºC. Finally, the prepared nano Ag-HAP coatings exhibited % 100 antibacterial activity against E. coli and S. epidermidis microorganisms. Keywords: Nanotechnology, hydroxyapatite, antibacterial, nano silver, Ti implant, plasma sprey coating