Highly Elastic Scaffolds Produced by Melt Electrowriting of Poly(L-lactide-co-epsilon-caprolactone)

A rapid and efficient system to adapt commercially available polymers for melt electrowriting (MEW) for the fabrication of micro-fibrous scaffolds is introduced. Poly(epsilon-caprolactone) (PCL) is currently the gold standard for MEW due to its low melt viscosity and its use in tissue regeneration. While several other polymers have been used for MEW, they involve small-scale custom synthesis meaning beyond PCL there is a scarcity of commercial polymers suitable for MEW. Furthermore, PCL has a long degradation time and lacks the elasticity needed for many applications. Poly(L-lactide-co-epsilon-caprolactone) (PLCL) is an elastic polymer with relatively fast degradation profile and is commercially available in high purity. Its high melt viscosity, however, makes it incompatible with MEW at normal operating temperatures. Rather than modifying the MEW machine, this study uses a simple pre-treatment of PLCL to tailor the melt viscosity. This treatment involves heating PLCL at 150 degrees C for 24-48 h to enable MEW printing into scaffolds at 110 degrees C with fiber diameters 14-40 mu m. Scaffolds maintained their elasticity after the thermal degradation process, becoming the first PLCL low-temperature MEW scaffolds. Moreover, this approach can be readily adapted by any MEW user without manipulating the polymer beyond the thermal treatment in an oven.