Structure and functionalization of mesoporous bioceramics for bone tissue regeneration and local drug delivery

Abstract

This review article describes the importance of structure and functionalization in the performance of mesoporous silica bioceramics for bone tissue regeneration and local drug delivery purposes. Herein, we summarize the pivotal features of mesoporous bioactive glasses, also known as 'templated glasses' (TGs), which present chemical compositions similar to those of conventional bioactive sol-gel glasses and the added value of an ordered mesopore arrangement. An in-depth study concerning the possibility of tailoring the structural and textural characteristics of TGs at the nanometric scale and their influence on bioactive behaviour is discussed. The highly ordered mesoporous arrangement of cavities allows these materials to confine drugs to be subsequently released, acting as drug delivery devices. The functionalization of mesoporous silica walls has been revealed as the cornerstone in the performance of these materials as controlled release systems. The synergy between the improved bioactive behaviour and local sustained drug release capability of mesostructured materials makes them suitable to manufacture threedimensional macroporous scaffolds for bone tissue engineering. Finally, this review tackles the possibility of covalently grafting different osteoinductive agents to the scaffold surface that act as attracting signals for bone cells to promote the bone regeneration process.

Nacre Compared to Aragonite as a Bone Substitute: Evaluation of Bioactivity and Biocompatibility

“…The need for biocompatible materials for clinical use has become of a growing concern, the focus of much of the recent biomedical research [4][5][6][7][8][9] . What would be the ideal material for the substitution or regeneration of damaged bone tissue?…”

Structure and biological activity of glasses and ceramics

“…They have elucidated details of surface alteration reactions and relate these to the steps in the Hench mechanism of bioactivity [23]. Vallet-Regi et al [75] discuss in more detail an approach to engineer bioactive glasses (templated glasses) by combining structural and textural concepts of silica mesoporous materials (SMMs) with chemical compositions similar to those of conventional bioactive sol-gel glasses. They also describe the functionalization of the three-dimensional-ordered arrangement of mesopores in SMM, in order to control the rate of release of the drug molecules which are incorporated into the pores.…”

Physicochemical characterization of drug nanocarriers

“…They are usually prepared from supramolecular assemblies composed of inorganic components (eg, silica nanoparticles) or organic and inorganic components (MOFs). 81 The pore structure 82 and pore size 83 of mesoporous materials influence their pharmaceutical potential in terms of loading capacity and drug release. 83,84 The incorporation …”