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Abstract Tissue biopsy is essential for obtaining samples for diagnosis in gastrointestinal (GI) diseases such as inflammatory bowel disease, ulcers, and cancer. However, conventional endoscopic tools often struggle to access confined and tortuous regions, including the small intestine and upper colon. While capsule devices offer improved navigation to these hard‐to‐reach areas, their biopsy mechanisms carry a relatively high risk of accidental tissue damage. To address this challenge, a magnetically actuated capsule device equipped with a magnetic biopsy unit and an integrated sensing module is proposed for safety‐enhanced biopsy. The magnetic biopsy unit incorporates a foldable linkage and dual magnets that provide a magnetic attraction‐based safety mechanism to prevent unintentional activation during locomotion. The sensing unit, composed of flexible sensors, enables real‐time detection of penetration displacement, allowing for controlled, on‐demand tissue sampling. Retrieving tissues are demonstrated safely from targeted GI tract regions, validating the system's efficacy. A sensor array is also seamlessly integrated to continuously track the capsule's position and orientation, ensuring accurate localization throughout the procedure. Therefore, the proposed sensory capsule device, together with the magnetic actuation and tracking system, offers a promising solution for safe, minimally invasive tissue biopsy in the complex and constrained regions of the GI tract.
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Capacitive sensing of triglyceride film reactions: a proof-of-concept demonstration for sensing in simulated duodenal contents with gastrointestinal targeting capsule system
Ingestible capsule systems continue to evolve to overcome drawbacks associated with traditional gastrointestinal (GI) diagnostic and therapeutic processes, such as limitations on which sections of the GI tract can be accessed or the inability to measure local biomarker concentrations. We report an integrated capsule sensing system, utilizing a hybrid packaging scheme coupled with triglyceride film-coated capacitive sensors, for measuring biochemical species present in the duodenum, such as pancreatic lipase and bile acids. The system uses microfabricated capacitive sensors interfaced with a Bluetooth low-energy (BLE)-microcontroller, allowing wireless connectivity to a mobile app. The triglyceride films insulate the sensor surface and react either with 0.01–1 mM lipase via hydrolysis or 0.07–7% w/v bile acids via emulsification in simulated fluids, leading to measurable changes in capacitance. Cross reactivity of the triglyceride films is evaluated in both phosphate buffered saline (PBS) as well as pancreatic trypsin solutions. The film morphology is observed after exposure to each stimulus to better understand how these changes alter the sensor capacitance. The capsule utilizes a 3D-printed package coated with polymers that remain intact in acid solution (mimicking gastric conditions), then dissolve at a duodenum-mimicking neutral pH for triggered opening of the sensing chamber from which we can subsequently detect the presence of pancreatic lipase. This device strategy represents a significant step towards using embedded packaging and triglyceride-based materials to target specific regions of the GI tract and sensing biochemical contents for evaluating gastrointestinal health.
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- Award ID(s):
- 1840468
- PAR ID:
- 10195707
- Date Published:
- Journal Name:
- Lab on a Chip
- Volume:
- 20
- Issue:
- 11
- ISSN:
- 1473-0197
- Page Range / eLocation ID:
- 2020 to 2032
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1039/d0lc00133c
