A deeper insight into the influence of the electric field densities in Melt-Electrowriting: Printing in the 4th Dimension

Abstract

Defined ordered structures for biomaterials and tissue engineering applications can be achieved by a variety of techniques, one of which includes the electrohydrodynamic (EHD)-based application of melt electrowriting (MEW), the extrusion of a molten polymer filament under pressure across a defined electric field. In this study, we investigate how to translate small fibremeshes which are usually formed on flat surfaces, to curved contours that would have more applicability to human anatomical structures. By modelling the electric field strength associated with the MEW process, we found that incorporation of a non conductive three-dimensional (3D) custom printed mould on the conductive collector plate offers the ability to accurately print patterns on non-flat surfaces successfully. Importantly, while the electric field strength is a constant in the MEW process; the electrostatic behaviour of the deposited polymer has the greatest impact on the accuracy of fibre patterning and stacking. Consequently, controlled fibre deposition was exhibited, provided that a constant electrical field strength and a continuous vertical distance between the nozzle and the mould is maintained.Overall, this study establishes the groundwork to support further developments in MEW technologies, from flat to anatomically relevant 3D structures in the fields of regenerative medicine and biofabrication.