CONICET | Buscador de Institutos y Recursos Humanos

Synthetic biodegradable polyesters are being extensively studied as biocompatible polymeric scaffolds for different tissue engineering applications. Poly(e-caprolactone) (PCL) and poly(diisopropylfumarate) (PDIPF) have probed to support adhesion, growth and differentiation of two osteoblastic cell lines, mouse calvaria-derived MC3T3E1 cells and UMR106 rat osteosarcoma, suggesting that these polymers could be useful in bone tissue regeneration. The blend of these polymers can modulate the biodegradation rate. The compatibility between PCL and PDIPF can be improved by ultrasound. For these reason solutions of PCL/PDIPF blends were exposed to high-intensity ultrasound. Size exclusion chromatography demonstrated that chain scission produced macroradical formation. Moreover, sonochemically induced reactions led to interpolymer radical coupling and block copolymer formation, which acted as compatibilizer between PCL and PDIPF. The compatibilized PCL/PDIPF blend had better properties than the non-sonicated one. In this work, highly-porous scaffolds of the compatibilized blend were prepared by electrospinning. A polymer solution 4% wt/V in chloroform was delivered through a spinneret at a flow rate of 1.5 mL/h, using an applied voltage of 0.7 kV.cm-1. The sample was collected on an aluminum foil covering the grounded aluminum collector. Experiments were performed during 1 h. The solution properties (solvent, concentration) and the processing conditions used in this work allowed the deposition of wet microspheres, which aggregated on contact with each other, instead of micro/nanofibers. The electrosprying generated a highly-porous interconnected structure formed by agglomerated microspheres. The obtained microspheres were irregularly shaped with approximately 5 mm in diameter and a narrow size distribution, as observed by scanning electron microscopy. Thus, the electrospraying technique could be a promising technique for the preparation of PCL/PDIPF scaffolds for bone tissue engineering. Additional experiments, varying solution concentration and processing parameters, could generate scaffolds with micro/nanofibrous morphology.