EVALUATION OF A PDLLA/45S5 BIOGLASS COMPOSITE: MECHANICAL AND BIOLOGICAL PROPERTIES
Résumé
The present study aims to characterize a composite made of poly-L,DL-lactic acid (P(L,DL)LA, Mv: 120 KDa) containing 30 wt% of 45S5 bioactive glass particles. Glass transition (around 52 degrees C) of the polymer was assessed by differential scanning calorimetry (DSC). The mechanical properties of the neat polymer and the composite were evaluated by tensile and compressive tests. From these tests, it was confirmed that the addition of bioglass into the polymer matrix leads to a slight decrease in tensile strength and an increase in elastic modulus. In vitro bioactivity of this composite was evaluated by immersion in a simulated body fluid (SBF) at 37 degrees C for different durations. Formation of hydroxyapatite crystals on the surface of the composite was recorded by scanning electron microscopy and confirmed by X-ray diffraction. Many hydroxyapatite crystals covered the surface of the composite after 14 days of immersion in simulated body fluid. Osteoblast cells MG-63 (human osteosarcoma cell line) were cultured in direct contact with the polymer and the composite. Cells morphology and attachment were analysed using SEM and MTT viability test. Scanning electron microscopy analysis showed the presence of cells at the surface of the composite. These results confirmed the biocompatibility of the composite and the positive effect of the bioglass on the osteoblast cells adhesion and proliferation on the composite.