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arXiv · 2605.06045

Kirigami-Structured Electronic Capsule for Long-Term Continuous Gastric Monitoring

Abstract

Ingestible electronic systems enable non-invasive, in situ sensing within the gastrointestinal (GI) tract, yet clinical translation has been limited by uncontrolled transit, short operational lifetimes, and unreliable wireless communication that prevent continuous monitoring. Here, we present a gastric-resident ingestible robotic platform that achieves week-long operation through integration of a bioinspired, electrically triggered release mechanism with a kirigami-enabled electronic architecture. A kirigami-patterned flexible printed circuit board spans the capsule body and deployable superelastic arms, enabling high-density integration of sensing, power management, and wireless modules within a constrained volume while tolerating large mechanical deformation during gastric residence. Stable retention and on-demand disassembly are achieved using thermally responsive polycaprolactone joints that transition from rigid to compliant states under electrical activation, avoiding dependence on variable chemical triggers. Reliable telemetry in the highly attenuating gastric environment is maintained using a dual-band Bluetooth Low Energy and sub-gigahertz module with RSSI- and throughput-aware adaptive transmission, balancing link robustness and energy consumption. We demonstrate long-term, continuous monitoring of gastric radiation exposure, enabling early detection of dose accumulation and providing a promising in vivo alternative to wearable or handheld dosimeters. Swine studies confirm stable gastric residence, sustained real-time telemetry, and safe gastrointestinal passage following triggered disassembly. This work establishes kirigami-enabled integration as a scalable strategy for long-term gastric-resident robotic systems.

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BibTeXRIS

Hen-Wei Huang, Claas Ehmke, Dawei Wang, Blake Smith, Ziyao Zhou, Rong Tan, David Werder, Crystan McLymore, Niels Neidlein, Emanuele Falli, Ali Imani, James McRae, Yeseul Jeon, So-Yoon Yang, Wesley S. Culberson, James Byrne, Giovanni Traverso. 2026-05-08. Kirigami-Structured Electronic Capsule for Long-Term Continuous Gastric Monitoring. https://arxiv.org/abs/2605.06045

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