Published online by Cambridge University Press: 20 March 2012
Physical properties of porous membranes made of biocompatible and biodegradable polymers have been studied. The membranes are intended to be used as scaffolds for the regeneration of soft and hard tissues. Polylactides, polycaprolactone and some of their derivates are biocompatible as well as biodegradable materials, and are used for the preparation of nanofibers and nanoporous membranes. These membranes also have comparative advantages as cellular scaffolds for tissue engineering since they can be prepared to mimic the morphology of the extra cellular matrix.
Chemical, physical, and biological properties of microfibers and scaffolds of polylactic acid (PLLA), as well as PLLA modified with hydroxyapatite nanoparticles and collagen (Col) are reported in this paper. The microfibers and the scaffolds were prepared by electrospinning. Morphology, diameter and porosity of the scaffold were determined by scanning electron microscopy and an image analyzer program. The microfibers are semicrystalline showing a shell of crystalline nanofibrils. The diameter of the fibers varied between 100 and 800 nm and the porous area of the membrane is between 60 and 80%. The mechanical properties of the microfibers and scaffolds were evaluated by microtensile tests and their behavior was simulated by using an original multiscale asymptotic homogenization model. Cultures of mesenchymal stem cells were used to evaluate their biological activity. Cell adhesion was observed in the modified PLLA scaffolds with grafted hydroxyapatite.