Estimation of the Core-Shell Formation Efficiency of Electrospun Collagen/Polylactic Acid Nanofibers

Abstract

Nanofibers are expected to become useful as medical materials including tissue engineering scaffolds, wound dressings, and carriers for drug delivery systems (DDS), because of their high specific surface area, porosity, anisotropy and the molecular order. Especially, the potential of core-shell nanofibers, that are composed of two types of materials for core and shell, are drawing attention to DDS materials because it is possible to suppress the diffusion of the drug from the core material through the shell material to realize a more precise controlled release. To use core-shell fibers in DDSs, the detailed characterization of the structure, including core-shell ratio, the surface area, and the core-shell formation efficiency is required. However, the structural analysis of individual fibers has not yet been fully carried out, although bulk properties have been well examined. Here, to obtain key structural information for DDS materials, we estimated the efficiency of polymer incorporation into complete core-shell fibers from cross-sectional images of the core-shell nanofibers by SEM observation.