Zn containing mesoporous bioglasses with enhanced textural and antibacterial properties produced by three modifications of the sol-gel method

Mesoporous bioactive glasses (MBGs) have potential applications in bone tissue regeneration around tooth implant and local drug delivery. Small amounts of zinc added to their composition could additionally provide antibacterial and ossteoinductive and anti-inflammatory properties. In this study, zinc-containing mesoporous bioactive glasses (5ZnO-25CaO-70SiO₂) were synthesised using three modified surfactant-assisted sol-gel methods: dilute water (MZ1), Stöber (MZ2), and microemulsion-assisted (MZ3). X-ray diffraction (XRD) analysis confirmed that MZ1 and MZ3 were amorphous, while MZ2 exhibited a ZnO crystalline phase. The synthesised particles showed uniform morphology with sizes ranging from 10 to 500 nm. Brunauer-Emmett-Teller (BET) analysis revealed that MZ1 had the highest specific surface area (726 m²/g), approximately 4.1 times higher than MZ3 (176 m²/g). Haemolysis testing showed that MZ1 and MZ2 were non-haemolytic, whereas MZ3 caused lysis of erythrocytes. All samples were biocompatible with periodontal ligament fibroblasts, maintaining cell viability above 80% after three days of incubation. Antibacterial assays indicated that MZ2 exhibited over 60% inhibition of P. intermedia in a dose-dependent manner, but only ~20% inhibition of P. gingivalis. MZ2 demonstrated a bacteriostatic effect and was most effective in reducing anaerobic bacterial populations among all tested groups. These results highlight the potential of Zn-containing mesoporous bioactive glasses as multifunctional biomaterials for periodontal tissue engineering, suitable for such applications as scaffolds, bone cements, bone-filling granules, and antibacterial implant coatings. Furthermore, MZ2 material due to its antimicrobial properties, can potentially be a material of choice in periodontitis/peri-implantitis therapy applications.