3D bioprinting is an emerging technology to fabricate tissues and organs by precisely positioning cells into 3D structures using printable cell‐laden formulations known as bioinks. Various bioinks are utilized in 3D bioprinting applications; however, developing the perfect bioink to fabricate constructs with biomimetic microenvironment and mechanical properties that are similar to native tissues is a challenging task. In recent years, decellularized extracellular matrix (dECM)‐based bioinks have received an increasing attention in 3D bioprinting applications, since they are derived from native tissues and possess unique, complex tissue‐specific biochemical properties. This review focuses on designing dECM‐based bioinks for tissue and organ bioprinting, including commonly used decellularization and decellularized tissue characterization methods, bioink formulation and characterization, applications of dECM‐based bioinks, and most recent advancements in dECM‐based bioink design.
Bioprinting is an emerging approach for fabricating cell‐laden 3D scaffolds via robotic deposition of cells and biomaterials into custom shapes and patterns to replicate complex tissue architectures. Bioprinting uses hydrogel solutions called bioinks as both cell carriers and structural components, requiring bioinks to be highly printable while providing a robust and cell‐friendly microenvironment. Unfortunately, conventional hydrogel bioinks have not been able to meet these requirements and are mechanically weak due to their heterogeneously crosslinked networks and lack of energy dissipation mechanisms. Advanced bioink designs using various methods of dissipating mechanical energy are aimed at developing next‐generation cellularized 3D scaffolds to mimic anatomical size, tissue architecture, and tissue‐specific functions. These next‐generation bioinks need to have high print fidelity and should provide a biocompatible microenvironment along with improved mechanical properties. To design these advanced bioink formulations, it is important to understand the structure–property–function relationships of hydrogel networks. By specifically leveraging biophysical and biochemical characteristics of hydrogel networks, high performance bioinks can be designed to control and direct cell functions. In this review article, current and emerging approaches in hydrogel design and bioink reinforcement techniques are critically evaluated. This bottom‐up perspective provides a materials‐centric approach to bioink design for 3D bioprinting.
more » « less- Award ID(s):
- 1705852
- PAR ID:
- 10367844
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 32
- Issue:
- 1
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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