Surface characterization of biomaterial interfaces

Any biomaterial application involves the creation of at least one interface. For instance, in a vascular graft, interfaces are created between the biomaterial and blood, and between the biomaterial and the walls of the blood vessel. In general very little is known about the basic interactions which give rise to a particular tissue response. Since the primary interaction occurs on the molecular level and in a very narrow interface width (<1nm), the surface properties on atomic scale take a central position dealing with bionaterials. The analytical methods must be capable of giving detailed information about both structural, chemical and compositional surface properties. Surfaces, particularly those types encountered in biomedical systems, present special problems for analysis: the measurement of only minute amount of material in the surface region, the separation of the surface signal from a preponderant bulk signal, the effective compatibility with the ultra high vacuum environment, the insulating nature. In the present work we address some of these issues discussing the role of surface science in the biomaterial research and development. In addition we show how the combination of surface sensitive analytical techniques (AES, SIMS, XPS, AFM) together with biological evaluation methods can contribute in better understanding biomaterial-tissue interaction