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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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Cellulosic Nanofibers Utilizing a Silicone Elastomeric Core to Form Stretchable Paper
Abstract Paper, an inexpensive material with natural biocompatibility, non‐toxicity, and biodegradability, allows for affordable and cost‐effective substrates for unconventional advanced electronics, often called papertronics. On the other hand, polymeric elastomers have shown to be an excellent success for substrates of soft bioelectronics, providing stretchability in skin wearable technology for continuous sensing applications. Although both materials hold their unique advantageous characteristics, merging both material properties into a single electronic substrate reimagines paper‐based bioelectronics for wearable and patchable applications in biosensing, energy generation and storage, soft actuators, and more. Here, a breathable, light‐weighted, biocompatible engineered stretchable paper is reported via coaxial nonwoven microfibers for unconventional bioelectronic substrates. The stretchable papers allow intimate bioconformability without adhesive through coaxial electrospinning of a cellulose acetate polymer (sheath) and a silicone elastomer (core). The fabricated cellulose‐silicone fibers exhibit a greater percent strain than commercially available paper while retaining hydrophilicity, biocompatibility, combustibility, disposable, and other natural characteristics of paper. Moreover, the nonwoven stretchable cellulose‐silicone fibrous mat can adapt conventional printing and fabrication process for paper‐based electronics, an essential aspect of advanced bioelectronic manufacturing.
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- PAR ID:
- 10485313
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Interfaces
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2196-7350
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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