Fuel-assisted sol-gel combustion synthesis of monticellite: Structural, mechanical, and biological characterization for tissue engineering

Silicate ceramics hold significant potential in tissue engineering, particularly as effective bone graft substitutes for the repair of bone defects. The current study explores the pivotal role of fuel selection in tailoring the properties of monticellite synthesized via sol-gel combustion technique using citric acid, glycine, and urea as fuels. X-ray diffraction patterns confirmed the formation of single-phasic monticellite at 1200 °C with glycine and urea as fuels, underscoring the essential role of fuel in phase formation. Monticellite synthesized with citric acid as fuel (MC) exhibited a higher surface area, which facilitated superior apatite formation, indicating enhanced bioactivity. In contrast, the increased particle size and effective grain growth of monticellite obtained through glycine (MG) contributed to mechanical strength values comparable to those of human cortical bone. Monticellite demonstrated strong antibacterial activity against clinical pathogens, coupled with notable anti-inflammatory properties and excellent hemocompatibility. MC, MG, and monticellite derived using urea (MU) scaffolds supported human-adipose-derived mesenchymal stem cell attachment and significant viability and osteogenic gene expression (BMP2, COLI, and OPN) when compared with monolayer culture. This comprehensive investigation underscores the substantial impact of fuel selection on monticellite's properties, offering a strategic approach for optimizing its characteristics with enhanced functionality for hard tissue regeneration. • The choice of fuel (citric acid, glycine, or urea) significantly influenced the phase composition of monticellite. Glycine and urea yielded single-phase monticellite. • Monticellite synthesized using citric acid exhibited a superior rate of apatite deposition, suggesting improved biomineralization and bioactivity, which are critical for bone tissue engineering applications. • Gene expression analysis revealed a significant upregulation of osteogenic markers, including type-I collagen (COL1) and osteopontin (OPN), confirming the material's ability to promote osteogenic differentiation of hADMSCs. • The monticellite scaffolds demonstrated notable antimicrobial efficacy, reducing the risk of post-implant infections and supporting their potential use in biomedical applications. • The material exhibited excellent hemocompatibility and significant anti-inflammatory effects, making it a promising candidate for biocompatible implants.