The adsorption behavior of glycidoxypropyl-trimethoxy-silane (GTMS) on titanium alloy Ti-6.5Al-1Mo-1V-2Zr was investigated by using X-ray photoelectron spectroscopy (XPS), Tafel polarization test, and electrochemical impedance spectroscopy (EIS). From the XPS results, it was found that the silane coverage on the titanium surface generally increased with GTMS concentration, with a slight decrease at concentration of 0.1%. Based on the relationship between isoelectronic point (IEP) of titanium surface and the pH values of silane solutions, adsorption mechanisms at different concentrations were proposed. The surface coverage data of GTMS on titanium surface was also derived from electrochemical measurements. By linear fitting the coverage data, it revealed that the adsorption of GTMS on the titanium alloy surface at 30 degrees C was of a physisorption-based mechanism, and obeyed Langmuir adsorption isotherm. The adsorption equilibrium constant (K-ads) and free energy of adsorption process (Delta G(ads)) were calculated to elaborate the mechanism of GTMS adsorption. Crown Copyright (C) 2012 Published by Elsevier B. V. All rights reserved.