Identifying emerging trends of protein hydrogels for biological scaffolding

Abstract

The strategies of bottom-up design of inorganic structures from biological templates enable cheap, ecofriendly and efficient fabrication of nano-structured materials. Here, template assembly of silica nanostructures were achieved using different protein hydrogels. Ovalbumin and fibrinogen gels were prepared by heat treatment at different pHs and protein concentrations. These hydrogels have been morphologically (SEM) and mechanically (rheology) well characterized. Next, a silica precursor is added, the condensation reaction is initiated and finally the protein hydrogel template is removed by calcination. A variety of 3D nanostructures ranging from highly porosity structures to spherical particles have been identified and characterized. Furthermore, it was observed that the fractal dimension of silica structures follow the same pattern than their corresponding templates. Consequently, the bio-scaffolding method proposed here helps the bottom-up assembly of silica precursors in nanostructures with defined three dimensional dimensions and provides a versatile route for the design of new architectures under green conditions.