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The technique of layer-by-layer (LbL) self-assembly has been used in development of biomimetic materials with superior mechanical and biological properties compared with synthetic composites.Heperin,as an anticoagulant,has been widely used in medicine,and fibrinectin is considered to promote the adhesion of endothelial cells.In this study,the biofunctional films of heparin and fibrinectin were fabricated through the LbL assembly technique on titanium surface for the anticoagulation and acceleration of the endothelialization simultaneously,and the stability of the assembled films was evaluated by immersing the samples into static phosphate buffer solution (PBS).Water static angle measurement and fourier transform infrared spectroscopy (FTIR) were employed to investigate the wettability and chemical change of the assembled films,and the changes in wettablility and chemistry of the surfaces with time of incubation in PBS for 24 h were also measured for the stability of the films.Quartz crystal microbalance with dissipation (QCM-D) was employed to monitor the assembly process in real time.FTIR showed that there was new peaks appearing after the assembly process indicating the linkage of heparin and fibrinectin.The contact angles were different among the films with various bilayers number.The stability of the assembled films was confirmed by the identification in FTIR and contact angles before and after incubation in PBS.QCM-D showed that the frequency shift and dissipation shift increased with the bilayer numbers,and the films became much more viscoelastical and hydrogel liked.The thickness of the assembled films could be controlled by changing the assembled layers.It seemed that the heparin and fibrinectin LBL coating could reach a growth limitation at around 8-10 bilayers.All the results revealed that stable self-assembled films of heparin and fibdnectin could be firmly formed on titanium surface.Our study demonstrates that LbL assembly of heparin and fibrinectin will provide a potential effective tool for biomaterial modification.