Dissolvable 3D printed PVA moulds for melt electrowriting tubular scaffolds with patient-specific geometry

Melt electrowriting (MEW) is an additive manufacturing technique capable of fabricating microfibre thermoplastic scaffolds that is growing in popularity for tissue engineering applications. MEW is able to produce micron-scale biocompatible constructs through electrodynamic jet deposition with a high level of control over fibre deposition. By depositing MEW fibres on a rotating cylindrical collector (mandrel), tubular constructs can be fabricated to mimic cylindrical anatomical tissues such as blood vessels. This proof-of-concept study leveraged the water solubility of polyvinyl alcohol (PVA) moulds to support tubular MEW scaffold fabrication in complex and patient-specific geometries. The dissolution rate of 3D printed PVA moulds was measured in water under constant stirring for 2 h. MEW scaffolds were printed on then removed from either PVA or non-dissolvable PLA moulds, and the preservation of the MEW scaffold morphology was assessed. The non-dissolvable PLA moulds significantly damaged the MEW scaffolds while the PVA dissolvable moulds enabled the preservation the of scaffold geometry and could be separated from the mould with ease. This study demonstrated the capability for MEW to be leveraged as a technique for producing anatomically relevant tubular structures.