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Abstract 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.
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Surface Patterning of Hydrogel Biomaterials to Probe and Direct Cell–Matrix Interactions
Abstract Due to their mechanical and structural similarity to native tissues, hydrogel biomaterials have gained tremendous popularity for applications in 3D tissue culture, therapeutic screening, disease modeling, and regenerative medicine. Recent advances in pre‐ and post‐synthetic processing have afforded anisotropic manipulation of the biochemical, mechanical, and topographical properties of biocompatible gels, increasingly in a dynamic and heterogeneous fashion that mimics natural processes in vivo. Herein, the current state of hydrogel surface patterning to investigate cellular interactions with the surrounding matrix is reviewed, both in techniques utilized and biological findings explored, and the perspective on proposed future directions for the field is offered.
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- PAR ID:
- 10443957
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Interfaces
- Volume:
- 7
- Issue:
- 21
- ISSN:
- 2196-7350
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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