| In order to research the Electrochemical behaviors of TiO2-xanticoagulation films, Ti-O/Ti Films with different composition, structure were deposited on commercial pure Ti by unbalanced magnetron sputtering system, The thickness of the films were tested using profilometer. The phase structure and composition were characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) respectively. Electrochemical impedance spectroscopy(EIS) and Mott-Schottky spectroscopy were studied by electrochemical workstation,UV-Vis spectroscopy was measured by self-made Electrochemical system (Xiamen University), thrombo-resistance of Ti-0 films was investigated by the platelet adhesion test, Main results were concluded as follows:1. X-ray diffraction (XRD) investigation indicated that Ti-0 films possessed mixture of nonstoichiometric structures with low O2 operating pressure, whereas mainly Rutile TiO2 crystalline structure with higher O2 operating pressure. Chemical compositions of the prepared Ti-O films, determined by XPS, convert from nonstoichiometric state to likely saturated titanium oxide (i.e. with O/Ti ratio increasing) with oxygen partial pressure increasing.2. Electrochemical tests, including EIS,Mott-schottky and US-Vis spectroscopy , were executed in Phosphate Buffer Solution(PBS) and PBS containing Fibrinogen (concentrations) solutions to investigate the electrochemical behaviors of the Ti-0 films. EIS results showed that reaction resistance drop obviously when fibrinogen was introduced, indicating interface electrochemical reaction between titanium oxide films and fibrinogen, According to Mott-schottky measurement, the Ti-0 films showed typical n type semi-conducting characteristic with relatively high donor density about 3.3～68.8×1025cm-3 . photo-current increase relatively when fibrinogen was mixed in PBS Solution in UV-Vis measurement, contraposing to interface charge transfer process.3. Platelets adhesion testing showed that Ti-O film with higher O/Ti ratio offered better blood-compatibility compared to ones with lower O/Ti ratio. The good blood compatibility was characterized by less platelet numbers adherent with less aggregation as well as less pseudopodium occurred.4. Non-stoichiometric titanium oxide films presented high space charge density and inclined to overflow electron to fibrinogen but accept it. So it decreased the fibrinogen adsorption on titanium oxide films and consequently have excellent anticoagulation property.
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