Fabrication and Characterization of Biodegradable Polymer Scaffolds Adapting Microfibrillar Composite Concept

In this work, we report on a technique for manufacturing of polymer scaffolds free from contact with toxic solvents. The method is adapted from the modified microfibrillar reinforced composites (MFC) concept. The objects of the investigation were biodegradable poly (L-lactide) (PLLA) and biocompatible poly (ethylene-vinyl alcohol copolymer) (EVAL). The polymers were melt blended and thereafter cold drawn, so that both of the components were converted in fibrillar state. After selective dissolving of the EVAL from the drawn bristles with mixture of propanol and water, the individual PLLA fibrils were isolated. By means of freeze-drying, ultrafine fibrous scaffolds were obtained. All materials under investigation were characterized by X-ray diffraction, differential scanning calorimeter, Fourier transform infrared spectrometry, scanning electron microscopy, and atomic force microscopy analysis. The experimental results provide evidence for the changes of the supra molecular organization of the blend partners during MFC manufacturing process, for the nanostructure and microstructure of the PLLA fibrils as well as for the three-dimensional architecture of the scaffolds. The in vitro studies show that the incubated in the presence of PLLA fibrils media does not reduce the cell viability and proliferative activity of the cultured cells. This kind of multiscale scaffolds might emulate the morphology of the natural extracellular matrix and represent an appropriate material for medical application. (C) 2013 Wiley Periodicals, Inc.