Micro/nanoscale electrohydrodynamic 3D printing and its application for living tissue regeneration

The extracellular matrix of human tissues possesses complex 3D micro/nanoscale fibrillar collagen structural features, which regulate cell differentiation, growth, and physiological functions. How to accurately simulate these micro/nanoscale structures and achieve controllable fabrication in vitro is of great significance for recapitulating functional tissue analogs. Electrohydrodynamic (EHD) 3D printing has emerged as a revolutionary approach for the controllable fabrication of micro/nanoscale biomimetic structures. This review summarizes the fundamental principles, fabrication processes of micro/nanoscale EHD printing as well as its application in regulating cell growth and tissue regeneration. The basic principles of micro/nanoscale EHD printing are elaborated. Subsequently, the latest advancements in solution-based, melt-based, cell-laden hydrogel-based, and multi-material composite EHD printing and their impacts on cellular behaviors are discussed. Its applications in the regeneration of active tissues such as cardiac, skeletal muscle, nerves, and vascular tissues are highlighted. Finally, future development challenges and potential solutions are investigated, aiming to facilitate the development of this technology in functional organ fabrication and clinical translation.