Injectable scaffolds which also deliver cells and bioactive molecules to augment bone healing overcome many of the limitations associated with current bone graft substitutes. The aim of this study was to develop and test a novel injectable scaffold that self-assembles isothermically in situ to form a biodegradable porous osteoconductive material, and to assess the viability of human mesenchymal stem cells (hMSC) seeded onto the scaffold. Rheological assessment was performed on three different molecular weights (Mw) of poly(lactic-co-glycolic acid) (PLGA) (26kDa, 53kDa and 92kDa) combined with differing ratios of polyethylene glycol (PEG) to control the temperature required for scaffold self-assembly. The strength (MPa) and stiffness (Young's Modulus) patterns of the scaffolds were assessed in compression. The cell viability, proliferation and distribution patterns of hMSCs seeded within the scaffold were assessed through various assays (Alamar Blue), confocal microscopy and micro-CT. The hMSC differentiation in osteogenic media was characterised by the identification of specific bone formation markers (e.g. alkaline phosphatase).Background/Study Aim
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