Herein, a method that uses direct‐ink‐write printing to fabricate engineering living materials (ELMs) that respond by undergoing a programmed shape change in response to specific molecules is reported. Stimuli‐responsiveness is imparted to ELMs by integrating genetically engineered yeast that only proliferate in the presence of specific biomolecules. This proliferation, in turn, leads to a shape change in the ELM in response to that biomolecule. These ELMs are fabricated by coprinting bioinks that contain multiple yeast strains. Locally, cellular proliferation leads to controllable shape change of the material resulting in up to a 370% increase in volume. Globally, the printed 3D structures contain regions of material that increase in volume and regions that do not under a given set of conditions, leading to programmable changes in form in response to target amino acids and nucleotides. Finally, this printing method is applied to design a reservoir‐based drug delivery system for the on‐demand delivery of a model drug in response to a specific biomolecule.
- NSF-PAR ID:
- 10139961
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 6
- Issue:
- 3
- ISSN:
- 2375-2548
- Page Range / eLocation ID:
- eaax8582
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Practitioner notes What is already known about this topic?
Constructionist perspectives shape important ideas about what we know about science learning, and notably in computer science fields.
One widely taken up example includes making, where learners use crafts to make interactive computational objects.
In life science, constructionism also provides insights about learning using digital media to model biological systems or interact with living materials.
What this paper adds?
This paper extends these perspectives by examining production and engagement when learners construct
with living materials—an approach that has only recently been possible with the development of accessible wet lab tools.We frame learning activities as a studio model—that emphasised application design, iteration and critique—to better assess the roles assembly, construction and speculative design play in production that uses living materials.
Our findings suggest that assembly is important for creating accessible points of entry to complex biological fabrication processes.
We also find that speculative design provides an opportunity for learners to extend their existing abilities beyond what is otherwise available given their expertise or access to resources, and thus expansively explore related ideas.
Implications for practice and/or policy
Assembly and speculative design have important places in constructionist‐driven production with living materials and could, therefore, be leveraged in practice.
- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1126/sciadv.aax8582
