Fabrication and characterization of collagen (shell)/thermoplastic polyurethane (core) composite nanofibers by coaxial electrospinning

Abstract

Coaxial-electrospinning is a new method used in tissue engineering and drug delivery field. It can spin nanofibers with shell-core structure through electrospinning of two polymer solutions. In this study, collagen was used as the outer layer or the shell and thermoplastic polyurethane (TPU) was used as the inner layers or the core. A series of tests were conducted to characterize the compound nanofiber and its membrane. Morphology and microscopy of the ultrafine fibers were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), whereas the fiber diameter distribution was understood using image visualization software (ImageJ) and measurements of solution viscosity and conductivity. Mechanical measurements were carried out by applying tensile test loads to samples which were prepared from electrospun ultra fine non-woven fiber mats. The results demonstrated that these composite nanofibers had the characters of native extracellular matrix and they could be designed as the scaffold for tissue engineering and functional biomaterials.