Title: SPR Biosensor Technique Supports Development in Biomaterials Engineering
Abstract: Various biomaterials are presently employed in the production of a very wide spectrum of medical implants. The choice of biomaterial is of course determined by the medical application for which it is intended and to date no one biomaterial has been found to be fully biocompatible and biotolerant. Furthermore, it is a well known fact that quite often implants must be removed due to tissue reactions and resultant health problems (Khan et al. 2008; Schierholz& Beuth, 2001). The key role in implant tolerance depends on a very short period of time during which the biomaterial surface first comes into contact with body fluids. During this time, water molecules come into contact with the surface of the biomaterial and the results of this reaction determine the further course of events. Water molecule interaction is generally dependent on surface nanostructure and highly dependent on its energy and hydrophobicity. The next stage of interaction, which depends on the presence of water on the biomaterial surface, is the creation of a thin protein film on this surface. A hydrophilic surface will collect a large amount of hydrophilic proteins readily available in body fluids, however these proteins are weakly adsorbed and can be easily removed or replaced by other molecules. A hydrophobic surface will adsorb proteins by their hydrophobic regions often causing changes in protein structure and biological activity. The final stage, cellular attachment, adhesion and proliferation depends on the profile of the adsorbed proteins, their accessibility and a proper spatial structure which enables expression of biologically active sites. Thus, the type of protein present on a biomaterial surface seems to be crucial for biomaterial tolerance in the human body. The most common experimental models developed to characterize protein adsorption on biomaterial surfaces involve the incubation of proteins in contact with a studied surface and the estimation of adsorbed proteins by a variety of methods including electrophoretic, enzymatic or immunoenzymatic approaches together with a number of labeling techniques. The common disadvantages of these techniques is that it is not possible to observe protein adsorption as a kinetic process and protein quantification is strongly limited by the sensitivity of the methods used, which is usually limited to nanograms per square millimeter. Surface