High-resolution electrohydrodynamic bioprinting: a new biofabrication strategy for biomimetic micro/nanoscale architectures and living tissue constructs

Abstract

Electrohydrodynamic (EHD) printing is a newly emerging additive manufacturing strategy for the controlled fabrication of three-dimensional (3D) micro/nanoscale architectures. This unique superiority makes it particularly suitable for the biofabrication of artificial tissue analogs with biomimetic structural organizations similar to the scales of native extracellular matrix (ECM) or living cells, which shows great potentials to precisely regulate cellular behaviors and tissue regeneration. Here the state-of-the-art advancements of high-resolution EHD bioprinting were reviewed mainly including melt-based and solution-based processes for the fabrication of micro/nanoscale fibrous scaffolds and living tissues constructs. The related printing materials, innovations on structure design and printing processes, functionalization of the resultant architectures as well as their effects on the mechanical and biological properties of the EHD-printed structures were introduced and analyzed. The recent explorations on the EHD cell printing for high-resolution cell-laden microgel patterning and 3D construct fabrication were highlighted. The major challenges as well as possible solutions to translate EHD bioprinting into a mature and prevalent biofabrication strategy were finally discussed.

Electrohydrodynamic Jet Printing: Introductory Concepts and Considerations

“…Bioengineering applications too are likely to see a sharp increase in the near future. [ 39,89,155,156 ] With more work in tissue regeneration, soft matter printing, and biocompatible hydrogels, EHD will play a significant role in achieving new milestones.…”

“…The aim of this work is to enhance understanding of the EHD process and highlight the intricacies involved to achieve the best possible result and resolution, based on existing methodologies, as well as those which we describe here. For applications of EHD printing, and current progress, several excellent reviews exist within the larger framework of additive manufacturing, [ 1,32–35 ] biological studies, [ 36–39 ] flexible sensors, [ 40 ] and electronics. [ 41 ] The references cited in this work are not exhaustive, and were chosen due to their instructive or illustrative nature.…”

Advances and challenges in bioprinting of biological tissues and organs

“…The printing speed in microfluidic‐assisted bioprinters can be ~15 times faster than conventional multi‐material bioprinters (0.4 vs. 0.025 m fibers/min), which can be employed for the timely bioprinting of gradients or heterogeneous structures 14 . The combination of 3D printing techniques with electrospinning has resulted in the emergence of a new class of 3D printers called electrohydrodynamic 3D printing with the ability to print mechanically strong constructs at nano‐scale resolutions 15,16 . However, the high working voltage of the electrospinning process has limited the inclusion of cells in the electrospun fibers.…”

Coaxial Electrohydrodynamic Bioprinting of Pre-vascularized Cell-laden Constructs for Tissue Engineering

“…Electrohydrodynamic (EHD) printing, with inherent advantages in generating micro/nanoscale droplets or filaments, was recently explored to process cells-laden hydrogel for fabricating functional tissue constructs with high resolution and cell viability[ 21 , 22 ]. It is a novel hybrid inkjet printing combined with the electrospinning technique.…”