Electrohydrodynamic printing: a potential tool for high-resolution hydrogel/cell patterning

Electrohydrodynamic printing has gained increasing attentions to fabricate micro/nanoscale patterns in a controlled and cost-effective manner. However, most of the existing studies focus on printing tiny dried fibres, which limits its applications in high-resolution cell printing. Here we investigated the feasibility of using electrohydrodynamic printing to pattern microscale liquid filaments. Process parameters like stage moving speed and substrate resistance were optimised to stably print polyvinyl alcohol (PVA) liquid lines with the smallest line width of 37.4 μm. Complex patterns like XJTU logo with constant or variable line width were successfully printed by dynamically adjusting the moving speed. Fluorescent microparticles, with a similar diameter to living cells, were patterned in a one-by-one manner along with the PVA filaments. It is envisioned that the presented electrohydrodynamic printing method could be potentially used to high-resolution hydrogel/cell patterning for the studies of microscale cell–cell interactions or organ printing.