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Title: BIOPOWER-IN-GUT: AN INGESTIBLE BACTERIA-POWERED BATTERY CAPSULE
We report an ingestible, millimeter-sized microbial fuel cell (MFC) capsule that can provide a realistic and practical power solution for ingestible electronics. The capsule integrates a pH-sensitive enteric membrane, a germinant-containing layer, and a microfluidic hydrogel-based anodic channel pre-inoculated with Bacillus subtilis spores as dormant biocatalysts, which are directly connected to an integrated MFC. When the pH-sensitive membrane dissolves in a designated gut location with a specific pH, the hydrophilic hydrogel in the anodic channel absorb the gut fluids washing the germinant to trigger the spore germination and generate microbial metabolic electricity in our world’s smallest MFC. When the capsule is designed to work in the human intestine, it generates electricity only in the neutral pH solution achieving maximum power and current densities of 64μW/cm2 and 435 μA/cm2, respectively, which are substantially higher than the other energy harvesting techniques.  more » « less
Award ID(s):
2100757 1920979
NSF-PAR ID:
10376400
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Technical digest SolidState Sensor Actuator and Microsystems Workshop
ISSN:
1539-204X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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