Melt Electrowriting of Elastic Scaffolds Using PEOT‐PBT Multi‐block Copolymer

Abstract

Melt electrowriting (MEW) is a powerful additive manufacturing technique to produce tissue engineering scaffolds. Despite its strength, it is limited by a small number of processable polymers. Therefore, to broaden the library of materials for MEW, we investigated the printability of poly(ethylene oxide terephthalate)‐poly(butylene terephthalate) (PEOT‐PBT), a thermoplastic elastomer. The effect of different printing parameters and material thermal degradation are studied. It is observed that the material is stable for >60 min at a printing temperature of 195 °C in a nitrogen environment. Next, two types of designs are printed and characterized: mesh‐like and semi‐random scaffolds. For both types of designs, PEOT‐PBT scaffolds reveal a higher yield strain, and lower Young's modulus as compared to control polycaprolactone scaffolds. Biological studies performed using mouse embryonic fibroblasts (NIH‐3T3) show good cell viability and metabolic activity on all print scaffolds. SEM imaging reveals actively migrating cells on PEOT‐PBT mesh scaffolds after 24 h of culture and 98.87% of pore bridging by cells after 28 days of culture. Immunofluorescence staining shows decreased expression of alpha‐smooth muscle actin from day 14 to day 28 in PEOT‐PBT mesh scaffolds. Overall, it is shown that melt electrowritten PEOT‐PBT scaffolds have great potential for soft tissue regeneration.