TY - JOUR
T1 - Development of Ingestible Thermometer with Built-in Coil Antenna Charged by Gastric Acid Battery and Demonstration of Long-Time in Vivo Telemetry
AU - Yoshida, Shinya
AU - Miyaguchi, Hiroshi
AU - Nakamura, Tsutomu
N1 - Funding Information:
This work was supported in part by Japan Science and Technology Agency (JST) Center of Innovation (COI) under Grant JPMJCE1303, and in part by the TERUMO Life Science Foundation.
Publisher Copyright:
© 2013 IEEE.
PY - 2021
Y1 - 2021
N2 - A safe and affordable ingestible thermometer measuring core body temperature has the potential to become a future healthcare device for versatile applications in daily life. In this study, we developed an ingestible thermometer charged by a gastric acid battery. The device can operate in bowels by using the charged energy in multilayer ceramic capacitors as a storage capacitor. Adopting this strategy for energy storage solves the issues related to a conventional button battery: risk of injury to the digestive tract, bad disposability, and degradation. Additionally, to make it easy to assemble a coil antenna and electrical circuits in the device automatically, we developed a fabrication process based on a vertical stacking process of printed circuit boards with coil patterns. The dimensions of the prototyped device were smaller than those of existing ingestible thermometers. In an experiment involving a dog, we successfully recorded the temperature in the digestive tract for 24 h in cycles of approximately 10 or 20 min, using a rectal thermometer and an existing ingestible thermometer as references. The temperature variations in time among our device, rectal thermometer, and existing ingestible thermometer were almost parallel. The recording ability of the core body temperature using our device has the potential to measure basal body temperature during sleep, the circadian rhythm, and fever type easily and robustly in daily life. Our ingestible thermometer is a step toward the development of sensors that can be swallowed for preventive medicine and health promotion.
AB - A safe and affordable ingestible thermometer measuring core body temperature has the potential to become a future healthcare device for versatile applications in daily life. In this study, we developed an ingestible thermometer charged by a gastric acid battery. The device can operate in bowels by using the charged energy in multilayer ceramic capacitors as a storage capacitor. Adopting this strategy for energy storage solves the issues related to a conventional button battery: risk of injury to the digestive tract, bad disposability, and degradation. Additionally, to make it easy to assemble a coil antenna and electrical circuits in the device automatically, we developed a fabrication process based on a vertical stacking process of printed circuit boards with coil patterns. The dimensions of the prototyped device were smaller than those of existing ingestible thermometers. In an experiment involving a dog, we successfully recorded the temperature in the digestive tract for 24 h in cycles of approximately 10 or 20 min, using a rectal thermometer and an existing ingestible thermometer as references. The temperature variations in time among our device, rectal thermometer, and existing ingestible thermometer were almost parallel. The recording ability of the core body temperature using our device has the potential to measure basal body temperature during sleep, the circadian rhythm, and fever type easily and robustly in daily life. Our ingestible thermometer is a step toward the development of sensors that can be swallowed for preventive medicine and health promotion.
KW - Biomedical electronics
KW - biomedical telemetry
KW - components
KW - manufacturing technology
KW - packaging
KW - sensor systems and applications
KW - system integration
KW - temperature measurement
KW - temperature sensors
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U2 - 10.1109/ACCESS.2021.3098333
DO - 10.1109/ACCESS.2021.3098333
M3 - Article
AN - SCOPUS:85111043144
VL - 9
SP - 102368
EP - 102377
JO - IEEE Access
JF - IEEE Access
SN - 2169-3536
M1 - 9490643
ER -