Mechanical strength and biocompatibility of bredigite (Ca7MgSi4O16) tissue-engineering scaffolds modified by aliphatic polyester coatings

Bredigite (Ca₇MgSi₄O₁₆) is a bioceramic with excellent bioactivity and bioresorbability; nonetheless, its inadequate mechanical strength and biocompatibility limit its tissue-engineering application. In this research, interconnected porous bredigite scaffolds were fabricated by sol-gel, sacrificial sponge replica and sintering processes for bone tissue engineering. In order to improve their strength and cytocompatibility, the scaffolds were coated with poly(lactic-co-glycolic acid) (PLGA) via immersion in acetone-based solutions containing different concentrations (5, 10 and 15% w/v) of the polymer. Based on the results, the PLGA coatings to 10% do not suppress the porosity characteristics of the scaffolds appropriate for tissue engineering. It was also found that the polymeric coatings significantly enhance the compressive strength of the ceramic scaffolds, where this alteration is improved by increasing the PLGA concentration of the coating solution. In addition, the viability of stem cells on the bredigite scaffolds are improved by using the PLGA coatings, with the optimal concentration of 10% PLGA according to MTT and cell attachment studies.