Methods for improved flexural mechanical properties of 3D-plotted PCL-based scaffolds for heart valve tissue engineering

Abstract

While porous poly-ε-caprolactone (PCL) scaffolds can be manufactured through 3D plotting with high regularity and reproducibility, it has been a challenge in previous research to mimic the highly flexible behaviour of the natural valve leaflets. In this study, an investigation is made of two separate approaches for the improved flexibility of 3D plotted PCL scaffolds for heart valve leaflets. Firstly, the scaffold geometry is radically altered towards a very open woven-like structure by adequately adapting the processing parameters during 3D plotting. Secondly, the base material itself is altered by blending a fraction of low-molecular weight poly-ethylene-oxide (PEO) into the PCL polymer. The scaffolds are 3D plotted for both series and their flexibility is evaluated in a uni-axial indentation experiment. The results are compared to those of the natural valve tissue and it is found that both approaches result in the desired reduction of the stiffness of the scaffold. © 2013 Journal of Mechanical Engineering.