Regulating surface roughness of electrospun poly(ε-caprolactone)/β-tricalcium phosphate fibers for enhancing bone tissue regeneration

Abstract Due to the natural microenvironment in the bone extracellular matrix, osteoblasts grow better on rougher and mechanically stronger substrates. Therefore, in this research, co-electrospinning poly(e-caprolactone) (PCL) with β-tricalcium phosphate (β-TCP) was applied to simulate the organic/inorganic fibrous structure of the natural bone ECM, and the method of self-induced crystallization was implemented to generate two sizes of shish-kebab structures on the fiber surface to adjust the surface roughness of the scaffolds. It was found that 10 wt% β-TCP and shish-kebab structure significantly enhanced the hydrophilicity, mechanical properties, biomineralization, and protein adsorption of the scaffolds, and the cellular response (proliferation and osteogenic differentiation) to these scaffolds was significantly up-regulated. It is considered that PT10-SK1.0 greatly improved its osteoinductive activity from both chemical and physical cues (the degree of osteogenic differentiation in the early-stage (ALP) and late-stage (OCN) increased by about 118.1% and 137.9%, respectively), and has great potential in promoting bone tissue regeneration. Keyways: Osteogenic differentiation; shish-kebab structure; PCL/β-TCP fiber; surface roughness; bone tissue engineering