Bio-inspired silica-collagen materials: applications and perspectives in the medical field

Silica and collagen are two of the most abundant substances in the Earth's geosphere and biosphere, respectively. Yet, their close association in nature has never been clearly demonstrated despite increasing evidence for the key role of silicon in mammalians. Foreseeing the therapeutic benefits of their association within composites or hybrids, a wide diversity of bio-inspired silica-collagen materials have been prepared over nearly 15 years. These works not only generated materials with a large range of structures and properties, from soft mineralized hydrogels to hard compact xerogels, but also provided more fundamental information about the interplay between polymer self-assembly processes and inorganic condensation mechanisms. Biological in vitro and in vivo evaluations suggest their bioactivity, cyto- and biocompatibility as well as controlled drug delivery properties. Hence they can now fully integrate the family of materials with high potential for the development of innovative biomedical devices.