Fabrication of heterogeneous scaffolds using melt electrospinning writing: Design and optimization

Abstract

Melt electrospinning writing (MEW) has recently emerged as a direct three-dimensional (3D) writing approach for the fabrication of orderly porous structures with well-defined geometrical features. In particular, it is widely used to produce tissue engineering (TE) scaffolds. The diameter of the electrospun fibers strongly affects the achievable resolution and consequently influences several other physical and mechanical properties of the fabricated scaffolds. However, compared to general extrusion-based additive manufacturing (E-AM) techniques, the factors influencing the size of the fibers are more complex owing to the presence of the electric field. In this study, several critical and effective process parameters in the MEW process are first investigated and then optimized to achieve the desired fiber diameter. Moreover, the fiber placement accuracy, which is essential for fabricating heterogeneous scaffolds with highly accurate features, is studied by considering the “lag effect” due to relative movement between the collector and the spinneret. In addition, an optimization strategy is proposed to avoid the error introduced by the “lag effect” while achieving the desired fiber diameter. This strategy can be used to adaptively control the process parameters. Finally, the proposed approach is validated and adopted for fabricating heterogeneous scaffolds to culture cells.