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Supplying continuous power is a major challenge in the creation and deployment of sensors and small robots for marine applications. Glucose-based enzymatic fuel cells (EFCs) are a possible solution for sustainably powering such devices when mounted on or implanted in living organisms. The two main barriers to developing implantable EFCs for marine organisms are their power output and in vivo feasibility. Ideally, an in vivo EFC should be minimally invasive, remain mechanically secure, and output relatively consistent power over a predefined lifespan, ranging from weeks to months. The shape and chemistry of EFC electrodes can each contribute to or detract from the overall power production potential of the cells. This paper assesses the feasibility of EFCs using the marine sea slug, Aplysia californica’s, hemolymph as an analyte and presents methods to enhance the power produced by EFCs by altering their chemistry and form factor. We found that perfluorodecalin-soaked cathodes and spirally-rolled cells demonstrated increased power output compared to their respective control specimens. Cells tested in Aplysia saline mirrored the power output trends of cells tested in hemolymph but with higher power output. This work suggests the feasibility of creating implantable EFCs for marine sea slugs that could one day serve as sustainable biohybrid robotic platforms.
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This content will become publicly available on November 1, 2025
Defensive polyketides produced by an abundant gastropod are candidate keystone molecules in estuarine ecology
Secondary metabolites often function as antipredator defenses, but when bioactive at low concentrations, their off-target effects on other organisms may be overlooked. Candidate “keystone molecules” are proposed to affect community structure and ecosystem functions, generally originating as defenses of primary producers; the broader effects of animal chemistry remain largely unexplored, however. Here, we characterize five previously unreported polyketides (alderenes A to E) biosynthesized by sea slugs reaching exceptional densities (up to 9000 slugs per square meter) in Northern Hemisphere estuaries. Alderenes comprise only 0.1% of slug wet weight, yet rendered live slugs or dead flesh unpalatable to three co-occurring consumers, making a potential food resource unavailable and redirecting energy flow in critical nursery habitat. Alderenes also displaced infauna from the upper sediment of the mudflat but attracted ovipositing snails. By altering communities, such compounds may have unexpected cascading effects on processes ranging from bioturbation to reproduction of species not obviously connected to the producing organisms, warranting greater attention by ecologists.
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- PAR ID:
- 10577206
- Publisher / Repository:
- American Association for the Advancement of Science
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 10
- Issue:
- 44
- ISSN:
- 2375-2548
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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