Fabrication of a biomimetic hierarchical surface replicated from a lotus leaf and in vitro cellular activities

Hierarchical surface structures have been used as tissue regenerative materials because they prompt an outstanding variety of cellular activities. Here, we sought to develop hierarchical structures on a poly(ε-caprolactone) (PCL) surface to mimic the distinctive natural hierarchical structures of a lotus leaf using the two processes of micro/nano-casting and plasma-etching. The surface roughness was the micro- (3.01-3.07 μm) and nanoscales (97±16 nm). To observe the efficacy as a biomedical substrate, the surface was investigated on the cell metabolic and osteogenic differentiation. High cell viability (> 2.9-fold) and calcium deposition (>2.1-fold) were observed on the surfaces versus the flat surfaces. From these results, we propose a new biomedical surface model that can induce high cellular activity at the cell-surface boundary for regenerating bone and dental tissues.