Density of nanopatterned surfaces for designing bone tissue engineering scaffolds

• Nanopillar pattern arrays with various densities were prepared by using capillary force lithography.
• Nanotopographical density directly influenced the adhesion and differentiation of human osteoblast-like cells.
• The optimum nanotopographical density was found for the bone mineralization of human osteoblast-like cells.

Design and manipulation of scaffolds are essential to improve cellular functions for regeneration of functional bone constructs in tissue engineering and regenerative medicine. Here, we describe that the nanotopographical density may have great potentials as an effective strategy for modulating behavior of human osteoblast-like cells. Using capillary force lithography, nanopillar pattern arrays were fabricated to investigate the effect of nanotopographical density on the behaviors of MG-63 cells. It was found that the nanotopographical structures promoted the attachment of MG-63 cells compared to the flat substratum as well as influenced the shape of them. In particular, the cell differentiation study showed that the 1:3 nanopatterned substratum (width to spacing ratio, defined by the ridge width of 1:3) exhibited the highest bone mineralization compared to other nanopatterned substrata and the flat substratum. These results demonstrated that the nanotopographical density may play a crucial role in regulating cell behaviors as an important considering factor for scaffold fabrication for bone tissue engineering applications.