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Abstract Bioresorbable electronic technologies form the basis for classes of biomedical devices that undergo complete physical and chemical dissolution after a predefined operational period, thereby eliminating the costs and risks associated with secondary surgical extraction. A continuing area of opportunity is in the development of strategies for power supply for these systems, where previous studies demonstrate some utility for biodegradable batteries, radio frequency harvesters, solar cells, and others. This paper introduces a type of bioresorbable system for wireless power transfer, in which a rotating magnet serves as the transmitter and a bioresorbable antenna as the remote receiver, with capabilities for operation at low frequencies (<200 Hz). Systematic experimental and numerical studies demonstrate several unique advantages of this system, most significantly the elimination of impedance matching and electromagnetic radiation exposure presented with the types of radio frequency energy harvesters explored previously. These results add to the portfolio of power supply options in bioresorbable electronic implants.
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Stretchable, dynamic covalent polymers for soft, long-lived bioresorbable electronic stimulators designed to facilitate neuromuscular regeneration
Abstract Bioresorbable electronic stimulators are of rapidly growing interest as unusual therapeutic platforms, i.e., bioelectronic medicines, for treating disease states, accelerating wound healing processes and eliminating infections. Here, we present advanced materials that support operation in these systems over clinically relevant timeframes, ultimately bioresorbing harmlessly to benign products without residues, to eliminate the need for surgical extraction. Our findings overcome key challenges of bioresorbable electronic devices by realizing lifetimes that match clinical needs. The devices exploit a bioresorbable dynamic covalent polymer that facilitates tight bonding to itself and other surfaces, as a soft, elastic substrate and encapsulation coating for wireless electronic components. We describe the underlying features and chemical design considerations for this polymer, and the biocompatibility of its constituent materials. In devices with optimized, wireless designs, these polymers enable stable, long-lived operation as distal stimulators in a rat model of peripheral nerve injuries, thereby demonstrating the potential of programmable long-term electrical stimulation for maintaining muscle receptivity and enhancing functional recovery.
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- Award ID(s):
- 1635443
- PAR ID:
- 10301646
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s41467-020-19660-6
