The effect of gelatin incorporation into electrospun poly(l-lactide-co-ɛ-caprolactone) fibers on mechanical properties and cytocompatibility

Very elastic poly(l-lactide-co-ɛ-caprolactone) (PLCL) (50:50) copolymer blended with gelatin was electrospun into microfibers from a hexafluoroisopropanol solution. PLCL fiber sheet exhibited the unique soft and flexible behavior while gelatin fiber was hard and brittle. As the gelatin content of PLCL/gelatin fibers increased, Young's modulus was increased, but the elongation was decreased compared to those of PLCL. However, fibers containing 10–30 wt% gelatin demonstrated an enhanced tensile strength with still high elongation to be beneficial for tissue engineering scaffolds. The cytocompatibility of electrospun fiber sheets was evaluated by fibroblasts (NIH-3T3) cell culture. The initial cell adhesion on various fibers after 5 h was somewhat similar, but in the order of PLCL > PLCL70/gelatin30 ≈ PLCL50/gelatin50 > PLCL90/gelatin10 ≈ gelatin > PLCL30/gelatin70. However, the cell proliferation exhibited a completely different and strong dependence on the fiber composition: a very high proliferation rate on PLCL90/gelatin10, followed by PLCL > gelatin > PLCL70/gelatin30. Such an enhanced effect of gelatin, especially at 10 wt% content, on strength and cytocompatibility of PLCL/gelatin fibers would be very preferable for tissue engineering scaffolds.