Investigation of in vitro bioactivity, cytotoxicity, and neurogenic characteristics of spray-dried Al-doped bioactive glass

Due to advancements in bioceramics, bioactive glasses (BGs) are increasingly acknowledged as viable options in the domains of tissue and bone engineering, owing to their excellent characteristics such as non-toxicity, bioactivity, and biocompatibility. Nevertheless, the use of these materials is limited due to a lack of inherent neurogenic properties. To mitigate this limitation, we aimed to investigate the synthesis and properties of undoped and Al-doped 58S bioactive glass (BG) prepared via spray drying and focused on evaluating the impact of Al dopant concentration (5, 10, and 15 mol %) on their structure, morphology, bioactivity, cytotoxicity, and neurogenic characteristics. The results confirm the amorphous nature of both undoped and Al-doped BG microspheres while revealing a shift in morphology from smooth spherical particles to concave spheres with higher Al concentrations, along with their formation mechanism discussed. In addition, in vitro bioactivity, evaluated by immersing the specimens in simulated body fluid, demonstrates a decrease in hydroxyapatite formation with increasing Al content, while cytotoxicity indicated that all specimens are non-toxic, with Al doping even exhibiting a slight enhancement in cell viability. These findings provide valuable insights into the potential of Al-doped 58S BG microspheres for biomedical applications.