Facile synthesis of silver loaded bioactive glass ceramic and reinforced composite scaffold using acrylic polymer for bone tissue engineering applications

Bioactive glasses are mainly used in tissue engineering applications such as fabrication of resorbable scaffolds, bioactive composite bone cements, etc., as they release Na⁺, Ca²⁺, Mg²⁺, PO₄^3- ions, which aid in repairing and regenerating damaged tissues. The inability of fabricated composite scaffolds or bone cements to impart antimicrobial activity may lead to bacterial infection and other inflammatory responses. This work attempted to develop acrylic polymer and bioactive glass composite bone cement with antibacterial activity. Initially, bioactive glass powders were synthesized by a simple sol–gel method with different concentrations of silver (Ag) to induce antibacterial properties. The physicochemical properties, like thermal stability and phase change, etc. with respect to the concentration of Ag loading were evaluated. The results showed that no significant structural and compositional change occurred due to heat treatment and the amorphous phase could be maintained upto 700°C. Electrochemical analysis (Differential Pulse Voltammetry) of bioactive glass in simulated body fluid showed the peak current signifying the gradual release of Ag⁺ ions. The released Ag⁺ ions from the bioactive glass powders showed inhibition against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli bacterial systems. The cytocompatibility study of Ag-loaded bioactive glasses in MG-63 human osteoblast like cell lines showed no toxic effect for all the concentration ranges attempted. The developed Ag-loaded bioactive glass powder with optimum antimicrobial property and good cell viability was subsequently used as reinforcement in Poly Methyl Methacrylate (PMMA) matrix to develop porous composite scaffold using porogen leaching technique. Mechanical study (compression test) proved that the fabricated scaffolds have sufficient rigidity, and the thermal degradation phenomenon could be controlled by the addition of bioactive glass powders to the PMMA matrix. This interconnected porous scaffold with good bioactivity, antimicrobial property, mechanical rigidity and cell compatibility is expected to be potent in bone tissue engineering applications.