Morphology Control of Electrospun Fiber Membrane Using NaCl Crystallization

초록

Electrospun fibers have been explored for applications such as high performance filters and biomaterials for vascular grafts, wound dressings or tissue engineering scaffolds. Electrospinning offers an interesting means to form protein fibers of nanometer scale diameters with large surface areas while maintaining high porosity. Not only biodegradable synthetic polymers but also natural polymers like silk and collagen have been electrospun to generate nanofibers. However, the pore size of the typical electrospun membranes was too small for the fibroblast or stem cell to penetrate through the membrane and the membrane surface was too smooth to be applied onto epidermis as artificial skin. In the present study, we explored the preparation of the poly(lactide-co-glycolide) (PLGA) membrane by the modified electrospinning process in which a NaCl solution reservoir was used as the collector. Surface morphology of the membrane was controlled by varying the concentration and the crystallization time of NaCl. Rough surface of the electrospun membrane simulating the rete ridge morphology of epidermis was obtained by dissolving NaCl in water and the hydrophobicity of PLGA was expected to be reduced. The structure and morphology of the membranes were investigated by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS).