Bioglass® and resulting crystalline materials synthesized via an acetic acid-assisted sol–gel route

In this study, we report on the synthesis of a bioactive glass powder with the original 45S5 composition (Bioglass®) by means of an acetic acid-assisted sol–gel route. A glassy material was obtained after the gels underwent a thermal stabilization treatment at 600 °C for 3 h. Above this temperature, the heat-treated gels crystallized partially, forming a sodium-calcium-silicate Na2CaSi2O6 phase. Even after crystallization, this material showed in vitro bioactivity in simulated body fluid after 12 h, when the formation of hydroxycarbonate apatite on the material surface was identified by X-ray diffraction. Not surprisingly, microbiological assays revealed that these gel-derived materials appear to have an antibacterial effect against Pseudomonas aeruginosa (ATCC 27853)—a Gram-negative bacterium that is noted for its environmental survival versatility, ability to produce biofilm and resistance to some antibiotics. Thus, using common precursors that are widely available, relatively cheap, simple to use, and which result in gels with low stabilization temperature, it was possible to explore the versatility of sol–gel processing to obtain the golden standard 45S5 bioglass.