Novel porous poly(propylene fumarate-co-caprolactone) scaffolds fabricated by thermally induced phase separation

Scaffolds with porous structures are highly applicable for tissue engineering and regenerative medicine. In the present study, 3-dimensional poly(propylene fumarate-co-caprolactone) [P(PF-co-CL)] scaffolds were fabricated from a P(PF-co-CL)-dioxane-water ternary system through thermally induced phase separation (TIPS). Cloud points of P(PF-co-CL) in dioxane-water solutions increased with increased solute concentration, but increased dioxane composition decreased cloud point. Among 3 polymer concentrations (4, 8, and 12 wt%), 8 wt% P(PF-co-CL) scaffolds exhibited the best pore interconnectivity, with large, regular sized pores. Scaffolds were formed in 3 solutions with different dioxane-water ratios (74/26, 78/22, and 82/18 wt/wt); the 78/22 wt/wt scaffold had finger-shaped patterns with better interconnectivity than scaffolds from the other two ratios. Higher dioxane-water ratios resulted in a larger contact angle and thus less wettability for the fabricated scaffold, while scaffolds fabricated from higher concentrations of P(PF-co-CL) or high dioxane-water ratios had better biomineralization after soaking in simulated body fluid. In vitro cell viability testing showed the scaffolds had good biocompatibility with both bone and nerve cells. The results indicate that the polymer concentration and solvents ratio significantly affect the formation of porous structures, and optimum processing parameters were found to be 8% polymer concentration and 22% to 24% water content. These porous P(PF-co-CL) scaffolds fabricated via TIPS may be useful in various tissue engineering applications © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 226-235, 2017.