Performance assessment of a noninvasive swallowable biosensor deployment system in microgravity

Ingestible capsule endoscope technology has been a topic of research since the middle of the 20th century and has become a prominent area of study since the commercialization of capsule endoscopy in 2000. Ingestible telemetry capsules have been investigated by NASA in the last 20 years as a means for monitoring human body temperature during periods of physical exhaustion, but are limited in sensing time due to passage through the digestive system. In this work, we present a feasibility study on a sensor that attaches to the intestinal mucosa after being delivered to the bowel via ingestible capsule to be used on long distance space flights. This study included experiments conducted on NASA's Weightless Wonder aircraft and replicated in a laboratory setting on the ground. During these experiments, a capsule was activated, manually inserted into excised porcine small intestine, and then automatically implanted a sham sensor onto the mucosal lining. The purpose of the experiment was to determine if the automated implantation sequence is affected by microgravity. Eight trials conducted in each setting yielded successful implantation of four sham sensors in microgravity and three in earth gravity. Results suggest that automated implantation is feasible in both 1G and microgravity environments though design changes are necessary to significantly improve repeatability in both environments. Though improvements in reliability of the device are needed, this experiment is a benchmark for transferring capsule technology currently used only for visual screening of the bowel to health monitoring systems for space flights.