A Magnetic Capsule Robot With an Exoskeleton to Withstand Esophageal Pressure and Delivery Drug in Stomach

Abstract

Capsule medicine is one of the most widely used methods of drug delivery into the human digestive tract. Packaging drugs into capsules not only prevents contamination of the drug before reaching the destination, but also protects the digestive organs and respiratory tract from potential damages caused by drug reactions. After reaching the targeted digestive organs, the drugs in the orally taken capsules usually can only be released passively. Most capsule robots that have been proposed to release drugs actively did not consider the compressed pressure when they pass through the esophagus, which could lead to premature drug release. This letter proposes a magnetic capsule robot that can withstand intra-esophageal pressure and also has the advantages of active locomotion and on-demand drug releasing. The proposed robot consists of two permanent magnets, an exoskeleton, and a soft non-magnetic container. Thus, it can withstand intra-esophageal pressure when it passes through the esophagus. This capsule robot can enter the stomach for targeted drug releasing without leaking liquid drugs along the path. The behavior of the robot is controllable using an external magnetic field thanks to the ring-shaped magnets mounted on the robot's top and bottom sections. The non-magnetic drug container will not be influenced by the external magnetic field during the locomotion to prevent leakage. The experiments show that this proposed capsule robot is more relevant to real-world medical applications thanks to its unique capability to withstand esophageal pressure.