Manipulation Of Surface Nanostructure:Effect On Cell Adhesion

Biomaterials have found huge applications for disease diagnosis and treatment,replacement of damaged organs and functional improvement of certain tissues.Because such materials are important to human health,they have received considerable attentions by the researchers in recent years.For medical devices implanted inside human body,an inert material is required to prevent human cells from growing on it.On the other hand,for some medical materials applied for repairing the organism,it should provide biological activity to allow cells to adhere and differentiate on the surface to form a new organization eventually.Thus,the study of the interaction between cells and the material is essential to the applications of biological materials.Cell adhesion on the material surface is the first step which ensures the following cell behaviors,such as proliferation,differentiation,migration,and apoptosis.There are many factors that affect cell adhesion,including the nature of both the cells and materials.Among these,the physical and chemical properties of the surface play an important role on the adhesion process.In this thesis,the effects of nanostructures on cell adhesion have been studied.The contents were divided into two parts:(1)Surface nanostructures with controlled morphology were formed by the selfassembly of block copolymer(BCP).The effects of BCP properties(such as molecular weight,block ratio,etc.)and preparation conditions(such as different annealing solvents,annealing time)on the surface nanostructure were systematically studied,a series of nanostructures with different chemical composition were obtained.The adhesion of cells(mouse melanoma cells B16)to these nanostructured surfaces was further studied.Chemical composition will affect the hydrophobic of surface,which have an impact on cell adhesion,cells tend to adhere to the hydrophilic surface.(2)Surfaces with different content of roughness were prepared by coating silica nanoparticles with different diameters on glass slides.The adhesion of cells on these topographical structures was studied.Different diameter of nanoparticles will make the surface roughness difference,the greater the surface roughness,the less the amount of cell adhesion.