Degradable particulate composite reinforced with nanofibres for biomedical applications

Nanofibre-based structures and their composites are increasingly being studied for many biomedical applications, including tissue engineering scaffolds. These materials enable architectures resembling the extracellular matrix to be obtained. The search for optimized supports and carriers of cells is still a major challenge for the tissue engineering field. The main purpose of this work is to develop a novel composite structure that combines microparticles and nanofibres in reinforced polymeric microfibres. This innovative combination of materials is obtained by melting extrusion of a particulate composite reinforced with chitosan nanofibre meshes (0.05 wt.%) produced by the electrospinning technique. The reinforced microfibres were analysed by scanning electron microscopy and showed a considerable alignment of the chitosan nanofibres along the longitudinal main axis of the microfibre composite structure. The tensile mechanical properties revealed that the introduction of the nanofibre reinforcement in the particulate microfibre composite increased the tensile modulus by up to 70%. The various structures were subjected to swelling and degradation tests immersed in an isotonic saline solution at 37 degrees C. The presence of chitosan nanofibres in the particulate microfibres enhances the water uptake by up to 24%. The combination of good mechanical properties and enhanced degradability of the developed structures is believed to have great potential for various biomedical applications, including three-dimensional fibre mesh scaffolds to be applied in the field of bone tissue engineering. (C) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.