Design of copolymer PLA-PCL electrospun matrix for biomedical applications

Electrospinning is a quite consolidated technique to produce polymer nanofibrous matrices whose nanostructured morphology received great interest for application in the biomedical field i.e. in manufacturing matrices for tissue regeneration. Purpose of the work to design electrospun matrices made of Poly-L-lactide-co-poly-ε-caprolactone (PLA-PCL) 70:30 M ratio and their thoroughly physico-chemical and functional characterization. The ultimate goal of the research work is to obtain electrospun matrices suitable for circular substitution of esophageal defects. However the paper deals with very preliminary investigation mainly on electrospinning process and physical-chemical characterization of the electrospun matrices. The investigation on electrospinning process conditions involves polymer starting solution concentration between 20% w/v and 25% w/v, viscosity and surface tension, but also process parameters of electrospinning apparatus in order to optimize them at achieving homogeneous and reproducible nanofibers. The optimized electrospun matrices are characterized for their cytocompatibility, morphology (SEM analysis), polymer molecular structure in the solid state (FT-IR analysis) and thermal behavior (DSC analysis) and mechanical properties. In vitro degradation test is performed to evaluate electrospun matrix biodegradability. Results show good cytocompatibility for all polymer concentrations and electrospinning times. Moreover, the electrospun matrices biodegradation is slower with respect to matrices made by solvent casting method. The behavior is related to modifications in the polymer solid state and to polymer chains structure.