Bioactive and photocatalytically active surgical implant surfaces

• Improving biomedical implants via deposition of functionalised surface coatings is a growing field of research. An enhanced bone-bonding capability by induction of hydroxyapatite (HA) formation on the implant surface is a critical characteristic of a bioactive implant coating. In the field of implants, infections present a major problem, and result mostly from the contamination of the implant surface by bacteria during surgery. There is a need for antibacterial surface treatments, which can prevent the bacterial colonization and biofilm formation without compromising the biocompatibility of the implant itself.Crystalline TiO2 is not only a bioactive, non-resorbable material, it also exhibits excellent superhydrophilic and photocatalytic properties when irradiated with UV light. Thus, UV irradiation induced photocatalysis on crystalline TiO2 implant surfaces may present an effective method for decontaminating implant surfaces.In our study we have evaluated the influence of the main deposition parameters in the cathodic evaporation process on the microstructure of TiO2 thin films and correlated these to the photocatalytic activity (PCA) and in vitro bioactivity of the coatings.Bioactivity of all as deposited coatings was confirmed by the growth of uniform layers of HA after 7 days in phosphate buffered saline at 37 °C. Comparison of the HA growth after 24 hours indicated enhanced HA formation on coatings with small titanium dioxide grains of the rutile and the anatase phase. The results from the PCA studies showed that coatings containing a mixed microstructure of both anatase and rutile phases, with small grain sizes in the range of 26-30 nm and with a coating thickness of about 250 nm, exhibited enhanced activity as compared to other microstructures and higher coating thickness. The results of this study should be valuable for the development of new bioactive implant coatings with photocatalytically induced on-demand antibacterial properties.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Nanoteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Nano-technology (hsv//eng)

Keyword

TECHNOLOGY

TEKNIKVETENSKAP

Teknisk fysik med inriktning mot nanoteknologi och funktionella material

Engineering Science with specialization in Nanotechnology and Functional Materials

Teknisk fysik med inriktning mot materialvetenskap

Engineering Science with specialization in Materials Science

Publication and Content Type

ref (subject category)

kon (subject category)