Plasma-based surface engineering of metallic orthopedic materials and associated bio-interactions

【作者】 Hongqing Feng； Paul K.Chu；

【Author】 Hongqing Feng;Paul K.Chu;Department of Physics and Materials Science,City University of Hong Kong;

【机构】 Department of Physics and Materials Science,City University of Hong Kong；

【摘要】 Titanium and magnesium alloys are two important metallic implants in orthopedics and related medical fields. Titanium has good bio-compatibility and stability but lacks the robust anti-bacterial ability,whereas magnesium has a similar modulus as human bones and is also bio-degradable. Unfortunately,the degradation rate of magnesium alloys is often too fast under the physiological conditions and tissue healing can be compromised. By conducting surface treatment using plasma and related techniques,selected surface properties of these metals can be enhanced while the favorable bulk characteristics can be preserved. For instance,the anti-bacterial ability of titanium alloy and Ti O2 nanotube structures can be enhanced by Ag ion implantation followed by controllable Ag+ release,or by Au impregnation without the need for photocatalysis. The techniques can endow Mg alloys with improved surface corrosion resistance. For example,diamond-like carbon film formation,Zr,Ti,or Al surface alloying followed by O plasma immersion ion implantation,as well as rare earth ion implantation have been shown to deliver excellent results. The anti-bacterial effects of the surface-modified magnesium alloys are retained or even improved in some cases but opposite in other situations. The p H,magnesium ion concentration,surface effects,and bacteria response have been investigated systematically to elucidate the various mechanisms.更多还原

【Abstract】 Titanium and magnesium alloys are two important metallic implants in orthopedics and related medical fields. Titanium has good bio-compatibility and stability but lacks the robust anti-bacterial ability,whereas magnesium has a similar modulus as human bones and is also bio-degradable. Unfortunately,the degradation rate of magnesium alloys is often too fast under the physiological conditions and tissue healing can be compromised. By conducting surface treatment using plasma and related techniques,selected surface properties of these metals can be enhanced while the favorable bulk characteristics can be preserved. For instance,the anti-bacterial ability of titanium alloy and Ti O2 nanotube structures can be enhanced by Ag ion implantation followed by controllable Ag+ release,or by Au impregnation without the need for photocatalysis. The techniques can endow Mg alloys with improved surface corrosion resistance. For example,diamond-like carbon film formation,Zr,Ti,or Al surface alloying followed by O plasma immersion ion implantation,as well as rare earth ion implantation have been shown to deliver excellent results. The anti-bacterial effects of the surface-modified magnesium alloys are retained or even improved in some cases but opposite in other situations. The p H,magnesium ion concentration,surface effects,and bacteria response have been investigated systematically to elucidate the various mechanisms.更多还原