Functionalisation of periodic cellular bioactive glass scaffolds via the tailored design of compositional gradients

• Applicants: Professorin Dr. Delia Brauer; Privatdozent Dr.-Ing. Tobias Fey
• Subject Area: Synthesis and Properties of Functional Materials
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 461819532

Three-dimensional, highly porous and cellular bioactive glass scaffolds are of interest for tissue regeneration both in situ (by direct implantation into the patient) or ex situ (via tissue engineering). Owing to the pronounced crystallisation tendency of bioactive glasses, which inhibits the sintering of dense scaffold struts, these constructs often suffer from poor mechanical stability, e.g. compressive strengths below 1 MPa. This makes mechanical reinforcement necessary, which typically is achieved by combination with polymers. Here, a two-fold approach is addressed, which combines new scaffold geometries with inorganic functionalisation by the use of different glass types (e.g. silicate and phosphate) to obtain compositional gradients. The influence of diffusion processes during the sintering of glass layers is analysed to investigate the formation of such gradients. In addition, the influence of gradients on both degradation and ion release but also on scaffold mechanical stability will be characterised. New scaffold geometries will be obtained by additive manufacturing ofpolymer templates via stereo lithography, followed by scaffold synthesis via the replica approach. Besides the direct comparison of CAD models with scaffold micro-computer tomography scans to investigate templating precision, FEM simulations on real structuremodels will help to understand scaffold mechanical behaviour.

• DFG Programme: Research Grants