Tailoring Bulk and Surface Composition of Polylactides for Application in Engineering of Skeletal Tissues

Synthetic biodegradable polylactides have been used extensively to fabricate scaffolds for engineering skeletal tissues such as bone and cartilage. This chapter summarizes the application of polylactides in tissue engineering and shows strategies for tailoring its bulk and surface composition for optimized degradation rates, mechanical properties, and bioactivities that cannot be achieved with pure polylactide polymers. Hence, block copolymers and the use of blending as a cost-effective strategy are described here. Furthermore, polymeric networks are shown that are advantageous in porogen-leaching manufacture of scaffolds, in preventing crystallization during degradation, and in allowing the incorporation of hydrophilic chains. In addition, mechanical reinforcement of the polymer is achieved when organic inorganic composites of polylactides are formed. The last part of this chapter focusses on the modification of the surface to tailor the biocompatibility of polylactides only, without changing the bulk properties of the material. Surface modification by wet chemical processes and adsorption of biogenic multilayers of glycosaminoglycans is described that not only significantly improves biocompatibility but may also help to drive differentiation of stem cells into the desired lineage.