Page 122 - IJB-10-6

International

Journal of Bioprinting

REVIEW ARTICLE
Extrusion bioprinting from a fluid mechanics

perspective

Reza Gharraei 1 id , Donald J. Bergstrom 2 id , and Xiongbiao Chen *
1,2 id
1 Division of Biomedical Engineering, University of Saskatchewan, Saskatoon, Saskatchewan,
Canada
2 Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, Saskatchewan,
Canada

Abstract

Bioprinting is an emerging technology for fabricating intricate and diverse
structures that closely mimic natural tissues and organs for applications, such
as tissue engineering, drug delivery, and cancer research. Among the various
bioprinting techniques, extrusion-based bioprinting stands out due to its capability
to apply a wide range of biomaterials and living cells and its controllability over
printed structures. In bioprinting, bioink stored in a syringe is extruded through a
nozzle connected to the syringe and deposited onto the printing stage to form 3D
structures. The bioprinting process involves the flow of bioink through the syringe
and nozzle, then spreading on a printing stage. As a result, fluid mechanics plays a
crucial role in extrusion bioprinting. Notably, the biomaterials used in bioprinting
are typically non-Newtonian fluids, which have complex viscoelastic and thixotropic
behaviors; the influence of these behaviors on the bioprinting process has garnered
considerable attention, with various methods employed, including numerical
*Corresponding author:
Xiongbiao Chen simulations via computational fluid dynamics (CFD). This paper reviews the latest
(xbc719@mail.usask.ca) developments in the fluid mechanics of extrusion-based bioprinting to shed light
Citation: Gharraei R, Bergstrom DJ, on the challenges and key considerations involved. This review covers the topics of
Chen X. Extrusion bioprinting from a extrusion bioprinting (including driving mechanisms, printability, and cell viability),
fluid mechanics perspective. biomaterial rheology and its effect on bioprinting, multi-material bioprinting, and
Int J Bioprint. 2024;10(6):3973.
doi: 10.36922/ijb.3973 numerical simulations of bioprinting. Key issues and challenges are also discussed
along with recommendations for future research.
Received: June 18, 2024
Revised: August 9, 2024
Accepted: August 20, 2024 Keywords: 3D bioprinting; Fluid Mechanics; Viscoelasticity; Tissue engineering
Published Online: August 30, 2024
Copyright: © 2024 Author(s).
This is an Open Access article
distributed under the terms of the
Creative Commons Attribution 1. Introduction
License, permitting distribution,
and reproduction in any medium, Biofabrication is an emerging technology aiming to address the lack of tissue/organ
provided the original work is donors for transplantation in patients with severe injuries or diseases. Among various
properly cited. biofabrication techniques, three-dimensional (3D) bioprinting stands out for its ability
Publisher’s Note: AccScience to deposit cell-laden biomaterials (bioink) layer-by-layer to fabricate 3D constructs
Publishing remains neutral with with spatial control over scaffold design, enabling consistent production of patient-
1
regard to jurisdictional claims in
2,3
published maps and institutional specific 3D scaffolds. These scaffolds can be fabricated using the patient’s native
affiliations. biological materials. 4–7

Volume 10 Issue 6 (2024) 114 doi: 10.36922/ijb.3973