Robocasting of ceramic glass scaffolds: Sol-gel glass, new horizons

This article reports the first robocasting of a sol-gel based glass ceramic scaffold. Sol-gel bioactive glass powders usually exhibit high volume fractions of meso- and micro-porosities, bad for colloidal processing as this adsorbs significant portion of the dispersing medium, affecting dispersion and flow. We circumvent these practical difficulties, to achieve pastes with particle size distributions, high solids loading and appropriate rheological properties for extrusion through fine nozzles for robocasting. Scaffolds with different macro-pore sizes (300-500 ?m) with solid loadings up to 40 vol.% were robocast. The sintered (800 °C, 2 h) scaffolds exhibited compressive strength of 2.5-4.8 MPa, formed hydroxyapatite after 72 h in SBF, and had no cytotoxicity and a considerable MG63 cells viability rate. These features make the scaffolds promising candidates for tissue engineering applications and worthy for further in vivo investigations.