Dual-Phase Degradation and Hydroxyapatite Formation in Bioactive Glass Ceramic-Coated Aluminum Titanate Scaffolds for Bone Applications

Abstract

Aluminum titanium oxide scaffolds present a highly promising option because of their bioactivity, degradability, and antibacterial characteristics for bone tissue engineering. This makes them a viable alternative to metallic implants, which are susceptible to infection and have limited endurance. The present work aims to examine the impact of sol–gel bioactive glass ceramic coatings on Al₂TiO₅ pellets throughout immersion periods of 12 and 24 h (BG12, BG24). A dual-phase degradation process occurs in these coated scaffolds: first, ion release from the coating stimulates the creation of hydroxyapatite, followed by a progressive breakdown of the Al₂TiO₅ substrate, which further facilitates bone regeneration. An analysis of the structural and mechanical characteristics of coated and uncoated pellets was conducted by utilizing FESEM-EDS, XRD, TG-DTA, FTIR, BET, AFM, and micro-UTM techniques. Findings indicated that the scaffolds consist of a crystalline component of calcium magnesium silicate and calcium sodium aluminum silicate, together with a porous surface. Among the scaffolds, BG24 had the greatest compressive strength of 101 MPa. Bioactivity investigations demonstrated the production of hydroxyapatite in SBF, with a calcium-to-phosphorus ratio of 1.68 attained by BG24 after 14 days. Moreover, BG24 showed 90% cell survival at 100 μg mL^–1, so verifying its cytocompatibility based on biocompatibility and antibacterial tests. Antibacterial research also showed that it effectively stopped the growth of S. aureus and E. coli bacteria, which supports the idea that it might be able to lower the risk of infections in biomedical settings. Because of its improved bioactivity through a dual-phase degradation mechanism, BG24 is a promising option for bone tissue regeneration.