Dissolution, bioactivity and osteogenic properties of composites based on polymer and silicate or borosilicate bioactive glass

• Published in: Materials Science & Engineering C 2020-02, Vol.107, p.110340-110340, Article 110340
• Main Authors: Houaoui, A., Lyyra, I., Agniel, R., Pauthe, E., Massera, J., Boissière, M.
• Format: Article
• Language: English
• Subjects: Bioactive glass; Biodegradability; Biodegradation; Bioengineering; Bioglass; Biological activity; Biomaterials; Biomedical materials; Body fluids; Bones; Boron; Boron oxides; Borosilicate glass; Cell differentiation; Composite material; Differentiation (biology); Hydroxyapatite; Immersion; In vitro methods and tests; Life Sciences; Materials science; Mechanical properties; Mineralization; Molecular weight; Myosin; Osteogenic differentiation; Osteopontin; Polylactic acid; Polymer matrix composites; Polymers; Silicon dioxide; Submerging; Surgical implants; Tissue engineering
• ISSN: 0928-4931; 1873-0191
• DOI: 10.1016/j.msec.2019.110340

Bioactive glass (BAG)/Poly (Lactic Acid) (PLA) composites have great potential for bone tissue engineering. The interest in these materials is to obtain a scaffold with tailorable properties bringing together the advantages of the composites’ constituents such as the biodegradability, bioactivity and osteoinduction. The materials studied are PLA/13–93 and PLA/13-93B20 (20% of SiO2 is replaced with B2O3 in the 13–93 composition). To characterize them, they were dissolved in TRIS buffer and Simulated Body Fluid (SBF) in vitro. Over the 10 weeks of immersion in TRIS, the ion release from the composites was constant. Following immersion in SBF for 2 weeks, the hydroxyapatite (HA) layer was found to precipitate at the composites surface. By adding Boron, both these reactions were accelerated, as the borosilicate glass dissolves faster than pure silicate glass alone. Polymer degradation was studied and showed that during immersion, the pure PLA rods maintained their molecular weight whereby the composites decreased with time, but despite this the mechanical properties remained stable for at least 10 weeks. Their ability to induce osteogenic differentiation of myoblastic cells was also demonstrated with cell experiments showing that C2C12 cells were able to proliferate and spread on the composites. The Myosin Heavy Chain and Osteopontin were tracked by immunostaining the cells and showed a suppression of the myosin signal and the presence of osteopontin, when seeded onto the composites. This proves osteoinduction occurred. In studying the mineralization of the cells, it was found that BAG presence conditions the synthesizing of mineral matter in the cells. The results show that these composites have a potential for bone tissue engineering. [Display omitted] •Composites based on PLA and 13–93 bioactive glass with or without boron were studied.•The process and the nature of the bioactive glass allow to preserve the integrity of the polymer.•Boron contained in the bioactive glass tailors the dissolution rate of the composite.•The composites are able to induce a precipitation of calcium-phosphate in Simulated Body Fluid.•The composites induce the osteodifferentiation of C2C12 myoblastic cells.