The advent of wearable or body-borne electronics is rapidly changing how the Department
of Defense (DoD) provides diagnostic and therapeutic medical care to the warfighter.
Multiple DoD entities, from the U.S. Army Combat Capabilities Development Command’s
Chemical Biological Center, to the Defense Threat Reduction Agency, are seeking bioelectronics that can transform military medicine by providing medics with valuable information to improve acute care on the battlefield, and aiding military doctors providing prolonged care. For instance, bioelectronics sensors that measure multiple signals, including heartbeat and the secretion of metabolites in perspiration, can provide remote monitoring of warfighter medical status during operations. Next-generation bioelectronics can be delivered by implantation or can be swallowed so as to deliver therapeutic medications. A seamless integration of such bioelectronics with the soft, complex, and 3D shape of the human body is inherently challenging due to the geometrical, material, and mechanical dichotomies between the two. Conventional electronics are typically fabricated via planar, top-down processes on a rigid substrate. Conversely, the human body is an irregularly shaped and highly flexible, stretchable construct. Significant research has been dedicated to overcoming this challenge, including the design of stretchable, flexible electronics, the development of electronic skin tattoos, and the manufacturing of electronic textile and bioelectronic implants. This article proposes and highlights the advancement of a multimaterial and multiscale 3D printing approach that can enable the fabrication of bioelectronics to better interface with the human body. Specifically, the article highlights the development of (a) a freeform electronics fabrication approach that allows for the creation of complex 3D systems, and (b) the multimaterial-printing of an ingestible gastric
resident system that allows for non-surgical and needle-free delivery of wireless electronics into the human body.
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Single-vat single-cure grayscale digital light processing 3D printing of materials with large property difference and high stretchability
Multimaterial additive manufacturing has important applications in various emerging fields. However, it is very challenging due to material and printing technology limitations. Here, we present a resin design strategy that can be used for single-vat single-cure grayscale digital light processing (g-DLP) 3D printing where light intensity can locally control the conversion of monomers to form from a highly stretchable soft organogel to a stiff thermoset within in a single layer of printing. The high modulus contrast and high stretchability can be realized simultaneously in a monolithic structure at a high printing speed (z-direction height 1 mm/min). We further demonstrate that the capability can enable previously unachievable or hard-to-achieve 3D printed structures for biomimetic designs, inflatable soft robots and actuators, and soft stretchable electronics. This resin design strategy thus provides a material solution in multimaterial additive manufacture for a variety of emerging applications.
more » « less- NSF-PAR ID:
- 10400464
- Publisher / Repository:
- Nature Publishing Group
- 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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