Seeding Cells on Calcium Phosphate Scaffolds Using Hydrogel Enhanced Osteoblast Proliferation and Differentiation

Internal pores in calcium phosphate (CaP) scaffolds pose an obstacle in cell seeding efficiency. Previous studies have shown inverse relationships between cell attachment and internal pore size, which mainly resulted from cells flowing to the bottom of culture plates. In order to overcome this structure-based setback, we have designed a method for cell seeding that involves hydrogel. CaP scaffolds fabricated with hydroxyapatite, biphasic calcium phosphate, and β-tricalcium phosphate, had respective porosities of 77.0, 77.9, and 82.5% and pore diameters of 671.1, 694.7, and 842.8 μm. We seeded the cells on the scaffolds using two methods: the first using osteogenic medium and the second using hydrogel to entrap cells. As expected, cell seeding efficiency of the groups with hydrogel ranged from 92.5 to 96.3%, whereas efficiency of the control groups ranged only from 64.2 to 71.8%. Cell proliferation followed a similar trend, which may have further influenced early stages of cell differentiation. We suggest that our method of cell seeding with hydrogel can impact the field of tissue engineering even further with modifications of the materials or the addition of biological factors.