The effect of heat- or ultra violet ozone-treatment of titanium on complement deposition from human blood plasma
2010 (English)In: BIOMATERIALS, ISSN 0142-9612, Vol. 31, no 18, 4795-4801 p.Article in journal (Refereed) Published
Titanium (Ti) is a well known metallic biomaterial extensively used in dental, orthopaedic-, and occasionally also in blood contacting applications. It integrates well to bone and soft tissues, and is shown upon blood plasma contact to activate the intrinsic pathway of coagulation and bind complement factor 3b. The material properties depend largely on those of the nm-thick dense layer of TiO2 that becomes rapidly formed upon contact with air and water. The spontaneously formed amorphous Ti-oxide has a pzc similar to 5-6 and its water solubility is at the order of 1-2 micromolar. It is often subjected to chemical- and heat treatments in order to increase the anatase- and ruble crystallinity, to modify the surface topography and to decrease the water solubility. In this work, we prepared sol gel derived titanium and smooth PVD titanium surfaces, and analysed their oxide and protein deposition properties in human blood plasma before and after annealing at 100-500 degrees C or upon UVO-treatment for up to 96 hours. The blood plasma results show that complement deposition vanished irreversibly after heat treatment at 250-300 degrees C for 30 minutes or after UVO exposure for 24 hours or longer. XPS and infrared spectroscopy indicated change of surface water/hydroxyl binding upon the heat- and UVO treatments, and increased Ti oxidation. XRD analysis confirmed an increased crystallinity and both control (untreated) and annealed smooth titanium displayed low XRD-signals indicating some nanocrystallinity, with predominantly anatase phase. The current results show that the behaviour of titanium dioxide in blood contact can be controlled through relatively simple means, such as mild heating and illumination in UV-light, which both likely irreversibly change the stoichiometry and structure of the outmost layers of titanium dioxide and its OH/H2O binding characteristics.
Place, publisher, year, edition, pages
Elsevier Science B.V., Amsterdam. , 2010. Vol. 31, no 18, 4795-4801 p.
Titanium, Titanium oxide, Sol-gel, Blood plasma, Protein adsorption, Complement
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-56807DOI: 10.1016/j.biomaterials.2010.02.060ISI: 000277783100002OAI: oai:DiVA.org:liu-56807DiVA: diva2:322254