Surface features biomaterial design

The role of material surface features in biomaterial design is significant but poorly understood. Spatial control of cellular adhesion and growth is critically important in tissue engineering and related fields (1-4). Metals and plastics that are widely used for medical implants lack the molecular sequence and patterns crucial for normal cell function, and therefore often trigger aberrant cell responses in long term implantation (5). One promising approach is to introduce chemical or physical patterns on biomaterial surfaces, to achieve cell ftinctions more representative of in vivo behavior. 

In spite of the widespread utilization of affinity chromatography in cell separation, there are still a considerable number of problems to be solved. The most serious problem is that there is always a substantial fraction of cells that are non-specifically adsorbed on the matrix surface. The research on cell affinity chromatography done in the last decade seems to be more biased towards the improvement in operating conditions than to the development of specially designed matrices for cell separation as well as the characterization of immobilized proteins. Nevertheless, there is no doubt that further advances in affinity chromatography as an effective tool for cell separation virtually depend on the detailed understanding of the features of matrix materials and immobilized proteins, as well as their interacions at the interface. In this respect, cell affinity selection based on the specific interaction of cells with immobilized proteins on a solid-phase matrix is now a major area of interest in the field of biomaterials science. 

The biocompatible dimerized fatty acid (DFA)-based poly(aliphatic-aromatic ester) elastomers (PED) have been synthesized and studied for biomedical applications by El Fray et al. [194-200]. The design of nanostructured elastomeric biomaterials (mimicking biological materials) has been realized by using renewable resources, i.e., DFA. They are prepared by transesterification and polycondensation from the melt (see Section 7). The exceptional properties of DFA, e.g., excellent resistance to oxidative and thermal degradation, allow the preparation of PEDs without the use of thermal (often irritating) stabilizers. This is a particularly important feature making these polymers environmentally friendly and additive-free. What is equally important, by the use of the same method and stabilizer-free conditions, it was possible to prepare specially modified PED copolymers with an increased surface hydrophobicity. 

---