A facile method to fabricate poly(l-lactide) nano-fibrous morphologies by phase inversion

Scaffolds with a nano-fibrous morphology are favored for certain tissue engineering applications as this morphology mimics the tissue’s natural extracellular matrix secreted by the cells, which consists of mainly collagen fibers with diameters ranging from 50 to 400 nm. Porous poly(l-lactide) (PLLA) scaffolds obtained by phase inversion methods generally have a solid-wall pore morphology. In contrast, this work presents a facile method to fabricate highly porous and highly interconnected nano-fibrous scaffold sheets by phase inversion using PLLA of very high molecular weight (5.7 × 105 g mol–1). The scaffold sheets consist of nano-fibers within the desired range of 50–500 nm. When applying phase separation micromolding as a fabrication method besides the porous nano-fibrous morphology, an additional topography can be introduced into these sheets. Culturing of C2C12 pre-myoblasts on these nano-fibrous sheets reveals very good cell adhesion, morphology and proliferation. Excellent alignment of the cells is induced by fabrication of 25 μm wide microchannels in these sheets. These results warrant further evaluation of these sheets as tissue engineering scaffolds.