Coupling sol-gel with electrospray deposition: Towards nanotextured bioactive glass coatings

• Published in: Journal of the European Ceramic Society 2021-11, Vol.41 (14), p.7288-7300
• Main Authors: Müller, V., Jobbagy, M., Djurado, E.
• Format: Article
• Language: English
• Subjects: Bioactive glasses; Biomedical applications; Chemical Sciences; Electrostatic spray deposition; Material chemistry; Microstructural properties; Nanotextured coatings
• ISSN: 0955-2219; 1873-619X
• DOI: 10.1016/j.jeurceramsoc.2021.07.041

•Si-based bioactive glass coatings fabricated by coupling sol-gel and electrospray.•Compositional optimization of S85, S75, and S58 coatings on Ti6Al4V substrate.•Microstructural tunning of homogeneous BG coatings as a function of ESD parameters.•From very porous coral-type coating morphology to a more compacted cauliflower one.•In-vitro investigation after 24 h immersion in simulated body fluid. For the first time, the sol-gel method was coupled with electrostatic spray deposition (ESD) to fabricate nanotextured bioactive glass (BG) coatings with a controlled microstructure in a one-pot-process. Three BG compositions belonging to the SiO2-CaO-P2O5 system (S85, S75, and S58) were homogeneously deposited on metallic Ti6Al4V substrates starting from the atomization of precursor solutions. All coatings displayed an amorphous character, as confirmed by XRD. A wide variety of innovative BG morphologies were obtained, tuning the key parameters of ESD, leading from highly porous coral-like to compact reticular-type coatings. The bioactivity, in terms of apatite formation, of as-deposited coatings was tested by immersion in simulated body fluid solution. Textural properties were found to play an important impact in its biological performance. Highly porous ESD-coatings exhibited remarkable bioactivity for S75 and S58 compositions, compared with more compacted ones of equal formulations. S85 composition was found extremely reactive regardless of the coating microstructure.