Synthesis and Characterization of Bioactive Glass via CTAB Modified Sol-Gel Method for In Vitro Biological Activities

Bone defect repair methods have significant drawbacks and limitations. The discovery and development of bioactive glasses (BGs) have greatly advanced the treatment of bone diseases. BGs can uniquely bond to living tissues, including bone, due to the formation of a hydroxyapatite (HAp) layer on their surface. These glasses synthesized using various catalysts and structure-directing agents to enhance their biological activities. However, most catalysts generate toxicity, alter pH levels, and work at high concentrations. Similarly, many surfactants have limited surface areas, poor capacity to create well-defined mesoporous structures, and potential toxicity, reducing the bioactivity, biocompatibility, and biodegradability of the BGs. To address these issues, this study evaluates a bioactive glass synthesized via the sol-gel process, using low concentration CTAB as a structure-directing agent and citric acid as a catalyst. The phase composition, surface morphology, specific surface area, inner structure, crystal structure, elemental composition, and functional groups of the samples were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), transmission electron microscopy (TEM), selected area electron diffraction (SAED), energy-dispersive x-ray spectroscopy (EDS), and Fourier-transform infrared microscopy (FTIR) techniques, respectively. The in vitro bioactivity was tested by soaking samples in simulated body fluid and analyzing the HAp layer formation using XRD, SEM, and FTIR. In addition, the in vitro biocompatibility, and an in vitro biodegradability were measured. 0.3 M of CTAB (BG3) exhibited a larger specific surface area with spherical-shaped particles and pore volume with a mesoporous structure results better in bioactivity and biodegradability. Furthermore, all samples exhibited cell viability above 70%, indicating that the prepared materials are biocompatible. The findings highlight the potential of CTAB-modified BGs for biomedical applications, especially in bone repair and regeneration.