Chemistry of polymer and ceramic-based injectable scaffolds and their applications in regenerative medicine

Injectable scaffolds are a class of materials that stimulate the regeneration of functional tissue within the body. These materials are attracting interest in regenerative medicine because they allow tissue repair to occur after minimally invasive administration. From a chemistry perspective these materials present new challenges because they must convert from an injectable material to a solid or gel with appropriate kinetics and without damaging surrounding tissues. Furthermore, the material may have to carry living cells or sensitive drug molecules into the body. The demands placed on these materials have stimulated research into novel chemical and physical mechanisms of forming porous structures within aqueous conditions. This review examines the underlying chemistry of a number of classes of injectable scaffolds and sets out challenges for these materials in the future.