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This work establishes a means to exploit genetic networks to create living synthetic composites that change shape in response to specific biochemical or physical stimuli. Baker’s yeast embedded in a hydrogel forms a responsive material where cellular proliferation leads to a controllable increase in the composite volume of up to 400%. Genetic manipulation of the yeast enables composites where volume change on exposure to l -histidine is 14× higher than volume change when exposed to d -histidine or other amino acids. By encoding an optogenetic switch into the yeast, spatiotemporally controlled shape change is induced with pulses of dim blue light (2.7 mW/cm 2 ). These living, shape-changing materials may enable sensors or medical devices that respond to highly specific cues found within a biological milieu.
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4D Printing of Engineered Living Materials
Abstract 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.
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- Award ID(s):
- 2039425
- PAR ID:
- 10366748
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 32
- Issue:
- 4
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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