Effect Of TiO₂ Surface Topography Characteristics On Adsorption Behavior Of Single Protein System And Multiple Proteins System

Titanium dioxide has broad application prospects in the field of medical grafts,and it is also the most widely used metal material in clinic.The results show that the topological morphology of material surface will lead to changes in the number,density and orientation of the adsorbed proteins,which will affect the performance of the medical graft materials.Therefore,it is necessary to study the interaction between proteins and surfaces with nano-morphology for the development of multifunctional graft materials.However,the detailed mechanism of how different geometrical topographies affect the adsorption of proteins is still in its exploratory stage.Molecular Dynamics?MD?simulation was used to study the adsorption of bovine serum albumin?BSA?on TiO₂ surface with different nano-morphologies.Furthermore,the group adsorption behavior of multi-fibronectin on the periodic nanoscale structures surface was explored.In this paper,the?001?crystal plane of rutile is studied.The adsorption behavior of bovine serum albumin?BSA?on?001?rutile surfaces with different topological characteristics was studied by full atomic molecular dynamics simulation.It was found that the nanostructure could promote the adsorption of bovine serum albumin by analyzing the protein trajectory and adsorption energy.In addition,the binding mode between protein and surface is discussed.The protein can form more stable direct interaction with titanium atoms on rough surface,and can only adsorb indirectly through water layer on smooth surface.The effect of nanostructure distribution density on protein conformation is also discussed.When nanostructures are densely distributed,steric hindrance will hinder the protein molecule from spreading,which is helpful to improve the stability of protein conformation.A molecular model of rutile surface with periodic nanostructures was constructed,and the groups adsorption of multi-fibronectin on the rutile was studied.The adsorption behavior of multi-proteins was also discussed.In contrast with the result of smooth and rough surface,it was found that fibronectin was preferentially adsorbed on rutile nanostructures.Meanwhile,the orientation of fibronectin which was beneficial to promote cell adhesion was increased.It explained why the materials with periodic microscale functionalized zones has good osteoblast proliferation ability and excellent osteogenic differentiation effect.Therefore,the reasonable design of nano-morphology is the key to regulate protein adsorption and cell behavior.