Electrospun oriented gelatin-hydroxyapatite fibre scaffolds for bone tissue engineering

Tissue engineering of human foetal osteoblast (hFOB) cells was investigated on gelatin-hydroxyapatite (HA), crosslinked, electrospun oriented fibre scaffolds at the different hydroxyapatite concentrations of 0, 10, 20 and 25 wt% in the dry fibres and different fibre diameter, pore size and porosity of scaffolds. Rheological tests and proton NMR spectroscopy were conducted for all solutions used for electrospinning. It was found that 25 wt% HA-gelatin scaffolds electrospun at 20 kV led to the greatest cell attachment, cell proliferation and extracellular matrix (ECM) production while fibre orientation improved the mechanical properties, where crosslinked electrospun 25 wt% HA-gelatin fibre scaffolds yielded a Young’s modulus in the range of 0.5 to 0.9 GPa and a tensile strength in the range of 4 to 10 MPa in the fibre direction for an applied voltage of 20 to 30 kV, respectively, in the electrospinning of scaffolds. Biological characterisation of cell seeded scaffolds yielded the rate of cell growth and ECM (collagen and calcium) production by the cells as a function of time; it included cell seeding efficiency tests, alamar blue cell proliferation assay, alkaline phosphate (ALP) assay, collagen assay, calcium colorimetric assay, fluorescence microscopy for live and dead cells, and scanning electron microscopy (SEM) for cell culture from 1 to 18 days. After 18 days, cells seeded and grown on the 25 wt% HA-gelatin scaffold, electrospun at 20 kV, reached production of collagen at 370 g/L and calcium production at 0.8 mM