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Abstract This study explores a novel multi-material 3D printing technique for fabricating bioinspired hydrogel-Rochelle salt composites, focusing on optimizing concentration, cooling, and coating parameters to enhance material performance. The hydrogel-Rochelle salt composite is a promising material due to its lightweight, mechanical robustness, and piezoelectric properties, making it suitable for applications in sensors, medical devices, and structural materials. A series of concentration tests was conducted to determine the optimal Rochelle salt concentration for achieving efficient curing depth and exposure time. The results identified 50wt% hydrogel/50wt% Rochelle salt as the optimal concentration, providing a balanced curing profile essential for ensuring reliable layer adhesion and structural consistency. To enable controlled crystallization, a cooling process was introduced, with a cooling time of 15 minutes found to be sufficient for complete crystallization to a depth of 500 microns. Thermal imaging and microscopy confirmed the stability of the crystalline structure within the hydrogel matrix, ensuring the material’s functional integrity. Additionally, applying a coating to the printed structure significantly improved surface uniformity and durability, embedding the crystalline elements more effectively within the hydrogel matrix and enhancing the composite’s overall structural integrity. This coating process allowed the composite to withstand repeated printing cycles, facilitating the construction of layered, multi-material structures with improved mechanical and functional properties. The results highlight the importance of fine-tuning concentration, cooling time, and coating techniques to achieve optimal performance in multi-material 3D printing. By addressing these factors, the study demonstrates a reliable approach to producing hydrogel-Rochelle salt composites with high structural quality and piezoelectric functionality. This method not only enhances the material’s durability and adhesion between layers but also opens new possibilities for creating customized, multifunctional materials. The developed process holds significant promise for applications that require precise control over material properties, such as wearable electronics, medical implants, and lightweight structural components. In conclusion, this research provides valuable insights into the fabrication of hydrogel-Rochelle salt composites through advanced 3D printing techniques. The findings offer a foundation for future exploration in multi-material printing and composite fabrication, paving the way for the development of versatile materials with tailored properties for diverse applications.
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Phenotypically complex living materials containing engineered cyanobacteria
Abstract The field of engineered living materials lies at the intersection of materials science and synthetic biology with the aim of developing materials that can sense and respond to the environment. In this study, we use 3D printing to fabricate a cyanobacterial biocomposite material capable of producing multiple functional outputs in response to an external chemical stimulus and demonstrate the advantages of utilizing additive manufacturing techniques in controlling the shape of the fabricated photosynthetic material. As an initial proof-of-concept, a synthetic riboswitch is used to regulate the expression of a yellow fluorescent protein reporter inSynechococcus elongatusPCC 7942 within a hydrogel matrix. Subsequently, a strain ofS. elongatusis engineered to produce an oxidative laccase enzyme; when printed within a hydrogel matrix the responsive biomaterial can decolorize a common textile dye pollutant, indigo carmine, potentially serving as a tool in environmental bioremediation. Finally, cells are engineered for inducible cell death to eliminate their presence once their activity is no longer required, which is an important function for biocontainment and minimizing environmental impact. By integrating genetically engineered stimuli-responsive cyanobacteria in volumetric 3D-printed designs, we demonstrate programmable photosynthetic biocomposite materials capable of producing functional outputs including, but not limited to, bioremediation.
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- Award ID(s):
- 2011924
- PAR ID:
- 10506199
- Publisher / Repository:
- NPJ
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 14
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1038/s41467-023-40265-2
