Nature has evolved mechanisms to create a diversity of specialised materials through nanoscale organisation. Inspired by nature, we have designed hybrid materials with highly tailorable properties, which are achieved through careful control of their nanoscale interactions. These novel materials, based on a silicagelatin hybrid system, have the potential to serve as a platform technology for human tissue regeneration. Strong chemical bonds between the inorganic and organic constituents of the hybrid are essential to enable the precise control of mechanical and dissolution properties. Furthermore, hybrid scaffold porosity was found to highly influence mechanical properties, to the extent where scaffolds of particular strength could be specified based on their porosity. We envisage these Submitted to 2 hybrid materials will find a diverse application in both hard and soft tissue regenerating scaffolds.

Owing to their diverse range of highly tailorable material properties, inorganic/organic hybrids have the potential to meet the needs of biodegradable porous scaffolds across a range of tissue engineering applications. One such hybrid platform, the silica-gelatin sol-gel system, was examined and developed in this study. These hybrid scaffolds exhibit covalently linked interpenetrating networks of organic and inorganic components, which allows for independent control over their mechanical and degradation properties. A combination of the sol-gel foaming process and freeze drying was used to create an interconnected pore network. The synthesis and processing of the scaffolds has many variables that affect their structure and properties. The focus of this study was to develop a matrix tool that shows the inter-relationship between process variables by correlating the key hybrid material properties with the synthesis parameters that govern them. This was achieved by investigating the effect of the organic (gelatin) molecular weight and collating previously reported data.Control of molecular weight of the polymer is as an avenue that allows the modification of hybrid material properties without changing the surface chemistry of the material, which is a factor that governs the cell and tissue interaction with the scaffold. This presents a significant step forward in understanding the complete potential of the silica-gelatin hybrid system as a medical device.

Hybrid materials, with co-networks of organic and inorganic components, are increasing in popularity due to their tailorable degradation rates and mechanical properties. To increase mechanical stability, particularly in water, covalent bonding must occur between the components. This can be introduced using crosslinking agents such as 3-glycidoxypropyl trimethoxysilane (GPTMS). Attachment of GPTMS to polymers in aqueous conditions is hypothesized to occur by opening of the epoxide ring by nucleophiles on the polymer chain. Despite side reactions that occur between the epoxide ring of GPTMS and water, a range of NMR techniques showed that the carboxylic acid group of poly(g-glutamic acid) reacted with GPTMS. This result was used to identify the amino acids in gelatin that reacted most rapidly with the GPTMS epoxide ring, confirming that covalent bonding occurred in gelatin-silica hybrid materials. Journal Name RSCPublishing ARTICLEThis journal is

Considerable advances have been seen in materials with tailored nanostructures in recent years, owing, in part, to increased demands placed on material properties in fields, such as tissue regeneration and wound healing. This review focuses on the developments made in nanoporous bioactive glasses, their novel nanocomposites and their application to bone regeneration. Bioactive glasses have the ability to stimulate new bone growth as they dissolve in the body. Sol-gel bioactive glasses have a nanoporosity that provides sites for cell attachment and tailorable degradation rates. Importantly, the glasses can be made into interconnected porous structures that can be used as 3D templates for bone growth, although, because they are glasses, they cannot be implanted directly into sites that are under cyclic loading. Composites provide a partial solution to this problem, although their bioactive and degradation properties are not ideal, therefore novel nanocomposites are needed. The route to these potentially ideal materials is described.

Nature has evolved mechanisms to create a diversity of specialized materials through nanoscale organization. Inspired by nature, hybrid materials are designed with highly tailorable properties, which are achieved through careful control of their nanoscale interactions. These novel materials, based on a silica‐gelatin hybrid system, have the potential to serve as a platform technology for human tissue regeneration. Covalent interactions between the inorganic and organic constituents of the hybrid are essential to enable the precise control of mechanical and dissolution properties. Furthermore, hybrid scaffold porosity is found to highly influence mechanical properties, to the extent where scaffolds of particular strength could be specified based on their porosity. The hybrids also demonstrate a non‐cytotoxic effect when mesenchymal stem cells are cultured on the material. Cytoskeletal proteins of the cells are imaged using actin and vimentin staining. It is envisaged these hybrid materials will find a diverse application in both hard and soft tissue regenerating scaffolds.