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Abstract Engineered living materials (ELMs) are an emerging class of biohybrid materials with genetically programmable functionalities. Integrating ELMs with 3D bioprinting synergizes their biological programmability with the geometry‐driven functionality of 3D‐printed constructs, transforming these materials into practical products and engineering solutions. This integration also introduces a new paradigm in additive manufacturing that harnesses the “livingness” of encapsulated microorganisms as an active element in the fabrication process to create adaptive and evolving 3D constructs. This Perspective presents recent advances in 3D bioprinting and discusses current developments at the intersection of 3D bioprinting and ELMs. It highlights opportunities at the interface of these two emerging fields, including understanding the interactions between living and nonliving components of ELMs for bioink design, incorporating synthetic biology into bioprinting workflows, utilizing microbial growth as a postprinting fabrication process, and integrating shape‐morphing materials to enable the 4D printing of ELMs.
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Diffusion‐Based 3D Bioprinting Strategies
Abstract 3D bioprinting has enabled the fabrication of tissue‐mimetic constructs with freeform designs that include living cells. In the development of new bioprinting techniques, the controlled use of diffusion has become an emerging strategy to tailor the properties and geometry of printed constructs. Specifically, the diffusion of molecules with specialized functions, including crosslinkers, catalysts, growth factors, or viscosity‐modulating agents, across the interface of printed constructs will directly affect material properties such as microstructure, stiffness, and biochemistry, all of which can impact cell phenotype. For example, diffusion‐induced gelation is employed to generate constructs with multiple materials, dynamic mechanical properties, and perfusable geometries. In general, these diffusion‐based bioprinting strategies can be categorized into those based on inward diffusion (i.e., into the printed ink from the surrounding air, solution, or support bath), outward diffusion (i.e., from the printed ink into the surroundings), or diffusion within the printed construct (i.e., from one zone to another). This review provides an overview of recent advances in diffusion‐based bioprinting strategies, discusses emerging methods to characterize and predict diffusion in bioprinting, and highlights promising next steps in applying diffusion‐based strategies to overcome current limitations in biofabrication.
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- Award ID(s):
- 2103812
- PAR ID:
- 10482099
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Science
- Volume:
- 11
- Issue:
- 8
- ISSN:
- 2198-3844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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