"We are intrigued by a simple question: when you ingest a hot liquid, what happens as it travels down your esophagus and into the stomach?" said co-corresponding author C. Giovanni Traverso, MB, BChir, PhD, a gastroenterologist and biomedical engineer in the Division of Gastroenterology at the Brigham. "What we have found is that there are essentially two zones - the esophageal and the gastric - which means that we may be able to control and trigger gastrointestinal devices in these two regions with precision using warm water."
The first device the team tested was inspired by a blooming flower. This capsule-sized esophageal system with petal-like structures can close up like a bud when a warm fluid is ingested. The prototype, which was tested in pigs, unfurled in the esophagus, making contact with the esophageal wall and releasing milli-needles loaded with model drugs. When warm water was administered, the prototype fully closed and passed from the esophagus into the stomach.
The second device tested was a highly flexible, gastric resident device capable of releasing drug of extended - a device intended to stay in the stomach and release a regular dosage of a drug for weeks. Ingesting a warm liquid did not disturb the functioning of the device, but directly spraying warm water into the stomach with the aid of endoscope helped break down the device into pieces that could safely pass through the gastrointestinal tract in the pig model.
"Our approach was to employ design principles of transformable architected materials (mechanical metamaterials) whose shape and volume can be considerably altered through thermal actuation, as a new approach for developing gastrointestinal (GI) technologies with fast and robust response," said first author Sahab Babaee, a postdoctoral associate in the Langer Lab at MIT.
MEDICA-tradefair.com; Source: Brigham and Women's Hospital
