The development of novel calcium phosphate–polymer composite biomaterials with macro- to nano-level controlled hierarchical structures

Abstract

The synthetic technique to control hierarchical structure is essential for the development of highly functional materials. In this article, we review the challenges involved in creating new calcium phosphate–polymer composites as artificial bone that extends beyond autologous bone, by combining hierarchical structural control at the macro, micro, and nano levels. Gel-mediated processing is a powerful method for preparing macroscopically homogeneous calcium phosphate–polymer composites, and the biomimetic approach is effective for controlling the microscopic morphologies of calcium phosphate particles formed in polymeric hydrogel matrices. Octacalcium phosphate (OCP), which is a member of the calcium phosphate family, has a layered structure. Controlling the nanoscopic structure of OCP through the incorporation of organic molecules into the interlayers of its crystal lattice is a promising approach for adding new functionalities and improving the biological properties of composite materials.