Biomaterials with hierarchically defined micro- and nanoscale structure.

Biomaterials and tissue engineering are becoming increasingly important in biomedical practice, particularly as the population ages. It is clear that cellular responses to materials depend on structural properties of the material at both the micrometer- and nanometer scale, but general methods for controlling material properties on both of these scales are lacking. Using a hierarchical approach that mimics natural material formation processes, we developed a method to produce materials with controlled physical structures at both the micrometer- and nanometer scale. Our method is based upon a pre-organized micropatterned template and conformal transformation of the architecture with nanostructured minerals, namely hydroxyapatite. The newly developed materials were biocompatible with bone cells, induced a range of desirable cellular responses, and may therefore have direct application in bone tissue engineering. In addition, the design principles employed in this study can be extrapolated to the other classes of biomedical materials, including polymers, metals, ceramics or hybrid combinations.