Poly(ε-caprolactone) nanofibers with a self-induced nanohybrid shish-kebab structure mimicking collagen fibrils

A three-dimensional structure consisting of poly(ε-caprolactone) (PCL) nanofibers covered by periodically spaced PCL crystal lamellae, a self-induced nanohybrid shish-kebab (SINSK) structure, was created using electrospinning followed by a self-induced crystallization. The resulting structure that resembles the nanotopography of natural collagen nanofibrils in the extracellular matrix (ECM) of human tissues could serve as a tissue engineering scaffold. The formation mechanism of the self-induced shish-kebab structure was investigated with real-time observation of the crystallization process. Electrospun polylactic acid (PLA)/PCL nanofibers were also employed as shish elements to study the effects of different shish materials. The results show that the geometric dimensions of the shish-kebabs are highly related to the initial concentration of PCL solution. The shish material played an important role in the creation of shish-kebab structure. Cell assays with NIH 3T3 ECACC fibroblasts suggest that the nanotopography of the nanofiber surface with kebab crystals that mimic collagen fibrils facilitated the cell attachment and spreading of 3T3 fibroblasts cells.