Bioactive Glass Nanoparticles: From Synthesis to Materials Design for Biomedical Applications

Abstract

Thanks to their high biocompatibility and bioactivity, bioactive glasses are very promising materials for soft and hard tissue repair and engineering. Because bioactivity and specific surface area intrinsically linked, the last decade has seen a focus on the development of highly porous and/or nano-sized materials. This review emphasizes the synthesis of bioactive glass nanoparticles and materials design strategies. The first part comprehensively covers mainly soft chemistry processes, which aim to obtain dispersible and monodispersed nanoparticles. The second part discusses the use of bioactive glass nanoparticles for medical applications, highlighting the design of materials. Mesoporous nanoparticles for drug delivery, injectable systems and scaffolds consisting of bioactive glass nanoparticles dispersed in a polymer, implant coatings and particle dispersions will be presented.

The effect of tantalum incorporation on the physical and chemical properties of ternary silicon–calcium–phosphorous mesoporous bioactive glasses

“…Bioactive glasses (BGs) were first synthesized by Hench et al and are capable of chemically bonding with host tissue . Their bioactivity stems from ion release which can promote the development of a hydroxyapatite (HA) layer at the interface of the implant upon maturation in an aqueous medium . The HA develops from an exchange of ions between the glass and the medium resulting in the buildup of crystalline calcium phosphate compounds on the surface …”

“…This gives them high specific surface area, significantly greater than that of melt‐quenched BGs of similar composition . Bioactivity is proportionally influenced by specific surface area; therefore, MBGs can be designed with high bioactivity . Silica‐based MBGs have an amorphous structure which can accommodate various ions as network modifiers which disrupt the continuity of the glass network and form nonbridging silicon–oxygen bonds (Si‐NBO).…”

Nontoxic glasses: Preparation, structural, electrical and biological properties

“…This characteristic is attributed to the formation of a surface layer of hydroxylated apatite (HCA) similar to bone mineral. 11,12 The first bioactive glass, 45S5 Bioglass ® was reported by Hench et al in 1969. 6 After contact of bioactive glasses with the biological medium, ion release occurs that promotes the growth of a layer of carbonated hydroxyapatite on the surface of the glass.…”

Comparison of the effects of 45S5 and 1393 bioactive glass microparticles on hMSC behavior

“…Furthermore, mesoporous silica based glasses can be produced as micron and submicron sized SiO 2 ‐CaO or SiO 2 ‐CaO‐P 2 O 5 particles for the storage of signaling molecules and their localized release at the implantation site . The design of bioactive glass structures with nano to micro scale dimensions results in an increase in the glasses' bioactivity and enables the loading of therapeutic biomolecules to further stimulate the tissue regeneration process …”

“…In the clinic, BAGs are mainly applied in particulate form with a size of 90 to 1000 µm, and incorporated in bone defects as stacked particulates or putties. Lower micron to submicron‐sized bioactive glass particles are an attractive alternative to the currently clinically implanted micron to millimeter sized granules, as their smaller size results in a higher specific surface area (bioactivity) and makes them well‐suited for injection into bone defects or incorporation into composite scaffolds …”