The initial reactions of TiO2 with blood

✍ Scribed by Nygren, H�kan ;Tengvall, Pentti ;Lundstr�m, Ingemar

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 342 KB
• Volume: 34
• Category: Article
• ISSN: 0021-9304
• DOI: 10.1002/(sici)1097-4636(19970315)34:4<487::aid-jbm9>3.0.co;2-g

✦ Synopsis

The natural titanium oxide (TiO 2 ) layer of commercial sheet titanium was dissolved in hydrofluoric acid. A new oxide layer was grown by oxidation in nitric acid or by annealing at 700°C in air. At this temperature, reaction with nitrogen is unlikely. The purity of the oxidized sheet-titanium surfaces was investigated by Auger spectroscopy. The composition of both surfaces was TiO 2 with carbon impurities. The carbon content of the acid-oxidized titanium was 20 ± 2%, and the carbon content of the heat-oxidized titanium was 14 ± 2% The initial reactions of the TiO 2 surfaces with blood were investigated by short-time exposure to capillary blood and by detection of surface-adsorbed plasma proteins and cells with immunofluorescence. Antibodies specific to fi-brinogen, complement factor C1q, prothrombin/thrombin, and platelet membrane antigen were used, and the fluorescence was quantitated by computer-aided image analysis. The results show that serine proteases are the dominating proteins adsorbed onto annealed titanium (C1q = 67 ± 4.6; pt/t = 97 ± 0.2; fib = 47 ± 0.2). The adsorption of serine proteases was lower and the amount of fibrinogen was higher on the acid-oxidized surface (C1q = 46.3 ± 2.6; pt/t = 25 ± 2.9; fib = 64 ± 0.7). Platelets adhered and spread on the annealed titanium surface within 5 sec of blood-material contact. The number of adhering platelets was higher on the acid-oxidized surface.