ABSTRACT
Medical technology is one of the most important areas in which the interactions between animal or even human cells and biomaterial surfaces is of critical importance, in particular when it comes to designing endoprostheses or implants. When an implant is placed inside a living organism in order to fulfill structural or functional tasks, its biocompatibility is an unconditional prerequisite [1]. Very often the term biocompatibility means integration of the device into the target tissue and settling of the tissue-specific cells on its surface without creating a foreign-body response. But in many cases this is just a minimum requirement and the proper functionality of the implant requires strong and mechanically stable adhesion of the cells to the surface. Well-known examples of such implants are polymer tubes that are used to create bypasses, for instance, around plugged coronary arteries. In order to make the polymer surface blood compatible, endothelial cells (i.e. the cells that line the native blood vessels in vivo) are grown on the inner surface of the tubing, providing a vascular surface similar to the one inside the native vessels [2, 3]. Since the endothelial cells are exposed to significant shear forces by the circulating blood stream, their adhesion to the inner wall of the tubing is crucial and has to withstand considerable mechanical stress. In the exciting development of neuroprostheses, the requirements with respect to the cell-material contact zone are even more challenging as a real functional interfacing of the cells with electrodes or semiconductor devices is required. Besides mechanical stability, the cell-surface junction has to allow for a sensitive bi-directional transfer of electrical signals between the cells and the in vitro transducer [4, 5]. Animal cells interfaced with semiconductor devices have nowadays become emerging tools for drug and cytotoxicity screening in vitro [6].
