Chitosan-Hydroxyapatite Composite Scaffolds for the Controlled Release of Therapeutic Metals Ions

Abstract

Therapeutic ions such as calcium, magnesium or copper, play an essential role in maintaining the correct physiology of our organism. They act as cofactors of enzymes, modulating cell signaling and homeostasis through various pathways. Developing biomaterials for tissue engineering that control the concentration of these ions in vivo has been proven a successful strategy to tailor cell response and, ultimately, improve tissue regeneration. Among others, chitosan, a naturally sourced polysaccharide, and hydroxyapatite, the major component of the mineral phase of bone, showed encouraging results as ion carriers. This chapter offers an overview of the use of these two materials for the purpose. Initially, the main ions used in tissue engineering and their modes of action are listed. Then, the opportunities and challenges of chitosan and hydroxyapatite in the field are discussed: their key properties, their processing into composites and the methods to fabricate tissue engineering scaffolds.