Optimizing nozzle design in extrusion-based 3D bioprinting to minimize mechanical stress and enhance cell viability

Abstract

Extrusion-based three-dimensional bioprinting is a widely used technique for fabricating cell-laden constructs in tissue engineering and regenerative medicine. However, the mechanical stresses experienced by cells during the printing process can negatively affect their viability. This study examines the influence of nozzle geometry—specificallycontractionangleandoutletdiameter—onstressdistribution and its effects on cell survival. Through a combination of experimental analysis and theoretical modeling, the impacts of nozzle design on the balance between shear and extensional stresses during bioprinting are explored. The findings highlight the importance of optimizing nozzle parameters to minimize mechanical damage and enhance post-printing cell viability. The proposed model provides a framework for guiding nozzle design, offering insights into the development of customized bioprinting strategies that enhance construct fidelity and biological functionality. These results contribute to advancing bioprinting techniques for applications in tissue engineering and regenerative medicine.