Polymeric Microstructures with Shape-Memory Properties for Biomedical Use Built by Stereolithography

Abstract

Purpose The aim of this study was to design and build porous microstructures with shape memory behaviour using biodegradable poly(D,L-lactide-co-trimethylene carbonate) dimethacrylate macromers. These microstructures could be advantageous for tissue engineering and other advanced biomedical applications. Methods Porous structures with a gyroid pore network architecture showing average pore sizes of 930 μm and complete pore interconnectivity were prepared by stereolithography. Built structures were characterized by micro-computed tomography (μ-CT). Shape recovery and shape fixity of microstructures after 40% and 70% compression were evaluated. Results At 37 °C the flexible structures showed compression modulus values of 60 KPa and could be fully compressed. Thermal analysis showed that the built networks were amorphous with Tg values of 23 °C. After compression to 40 and 70%, shape fixity and shape recovery of the structures at respectively 0 °C and 37 °C was almost quantitative. Conclusions The well-defined pore network characteristics and the shape-memory properties of these structures allow their use as deployable tissue engineering scaffolds.