Fabrication and characteristic analysis of a poly(propylene fumarate) scaffold using micro-stereolithography technology.

Scaffold fabrication for regenerating functional human tissues has an important role in tissue engineering, and there has been much progress in research on scaffold fabrication. However, current methods are limited by the mechanical properties of existing biodegradable materials and the irregular structures that they produce. Recently, several promising biodegradable materials have been introduced, including poly(propylene fumarate) (PPF). The development of micro-stereolithography allows the fabrication of free-form 3D microstructures as designed. Since this technology requires a low-viscosity resin to fabricate fine structures, we reduced the viscosity of PPF by adding diethyl fumarate. Using our system, the curing characteristics and material properties of the resin were analyzed experimentally. Then, we fabricated waffle shape and 3D scaffolds containing several hundred regular micro pores. This method controlled the pore size, porosity, interconnectivity, and pore distribution. The results show that micro-stereolithography has big advantages over conventional fabrication methods. In addition, the ultimate strength and elastic modulus of the fabricated scaffolds were measured, and cell adhesion to the fabricated scaffold was observed by growing seeded cells on it. These results showed that the PPF/DEF scaffold is a potential bone scaffold for tissue engineering.