Understanding the properties of biologically active glassy materials for tissue engineering through modelling and experiment

Bioactive glasses (BGs) are amorphous materials exhibiting biocompatibility properties,gaining great interest as biomaterials for regenerative medicine. This work comprises twoparts. First, the bioactivity properties that fluoridated phosphate-based bioactive glasses(F-PBGs) exhibit once implanted, for dental repair applications, was studied. Second,the experimental design of cardiac patches, containing 45S5 bioactive glasses for cardiactissue engineering, was undertaken. [Continues.

Atomic-scale clustering inhibits the bioactivity of fluoridated phosphate glasses

© 2019 Adja B. R. Touré et al. Here, molecular dynamics simulations have been carried out on phosphate glasses to clarify the previously debated influence of fluoride on the bioactivity of these glasses. We developed a computationally advanced inter-atomic force field including polarisation effects of the fluorine and oxygen atoms. Structural characterisations of the simulated systems showed that fluoride ions exclusively bond to the calcium modifier cations creating clusters within the glass structure and therefore decreasing the bioactivity of fluoridated phosphate glasses, making them less suitable for biomedical applications

Multi-layer scaffolds of poly(Caprolactone), poly(glycerol sebacate) and bioactive glasses manufactured by combined 3d printing and electrospinning

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Three-dimensional (3D) printing has been combined with electrospinning to manufacture multi-layered polymer/glass scaffolds that possess multi-scale porosity, are mechanically robust, release bioactive compounds, degrade at a controlled rate and are biocompatible. Fibrous mats of poly (caprolactone) (PCL) and poly (glycerol sebacate) (PGS) have been directly electrospun on one side of 3D-printed grids of PCL-PGS blends containing bioactive glasses (BGs). The excellent adhesion between layers has resulted in composite scaffolds with a Young’s modulus of 240–310 MPa, higher than that of 3D-printed grids (125–280 MPa, without the electrospun layer). The scaffolds degraded in vitro by releasing PGS and BGs, reaching a weight loss of ~14% after 56 days of incubation. Although the hydrolysis of PGS resulted in the acidification of the buffer medium (to a pH of 5.3–5.4), the release of alkaline ions from the BGs balanced that out and brought the pH back to 6.0. Cytotoxicity tests performed on fibroblasts showed that the PCL-PGS-BGs constructs were biocompatible, with cell viability of above 125% at day 2. This study demonstrates the fabrication of systems with engineered properties by the synergy of diverse technologies and materials (organic and inorganic) for potential applications in tendon and ligament tissue engineering