Optimal fluid flow enhanced mineralization of MG-63 cells in porous chitosan scaffold

• The effects of flow rate in a perfusion culturing system on the maturation and mineralization of osteoblast-like MG-63 cell.
• Perfusion of medium increased the cell viability, cellular distribution and secreted high level of type I collagen.
• Perfusion of the culture medium can increase levels of ALP activity and OCN, but also enhance bone formation in vitro.

This study confirms the effects of flow rate in a perfusion culturing system on the maturation and mineralization of osteoblast-like MG-63 cells within genipin cross-linked chitosan scaffolds exhibiting distinct porous structures. The scanning electron microscopy revealed that chitosan scaffold exhibited homogeneous and interconnected pore structures with an average size of 100 μm. Perfusion of medium increased the cell viability, cellular distribution and secreted high level of type I collagen in first developmental period. Alkaline phosphatase (ALP) activity and osteocalcin (OCN) content of osteoblast culture in chitosan scaffold displayed maximal level at 0.24 mL/min of perfusion fluid rate. Calcium content analysis revealed a significant enhancement of deposited minerals on scaffold after 21 d cultured under flow perfusion. These results may be concluded that appropriate flow shear stress accelerated cellular differentiation and mineralization in 3D scaffolds. Therefore, dynamic culturing is a valuable and convenient tool for applications in the generation of three-dimensional bone tissue in vitro, and flow rate is an important operational factor.