Layered double hydroxides as controlled release materials

Layered double hydroxides (LDHs), also known as anionic clays, have particularly attracted attention in the field of bio-nanohybrid nanomaterials due to their unique properties, such as good biocompatibility, pH-dependent stability, and high anion exchangeability. Various biofunctional molecules, including deoxyribonucleotides, proteins, drugs, organic acids, food ingredients, and vitamins, have been successfully stabilized and preserved by incorporation into LDHs via intercalation reactions. In addition to the protected storage of biofunctional molecules, bio-related applications also require intact and controlled retrieval of these molecules from storage. The release properties of the intercalated molecules can be modified by various synthetic approaches which enable control of the size, chemical composition, charge density, and surface properties of the LDHs. In this chapter, we briefly summarize the techniques available for the stabilization and controlled release of biofunctionalized molecules in LDHs.