Medical Microrobot — A Drug Delivery Capsule Endoscope with Active Locomotion and Drug Release Mechanism: Proof of Concept

This paper presents a robotic capsule endoscope integrated a targeted drug delivery module (DDM) for digestive diseases treatments. The capsule with a big permanent magnet inside is wirelessly controlled and actively moves to target region in gastrointestinal tract by an electromagnetic actuation system (EMA). DDM is a separated body composed of a drug container and a non-power drug-releasing mechanism. The force to expel drug is generated by carbon dioxide gas pressure coming from a chemical reaction inside a propellant reservoir. Where the chemical reaction is activated by a mechanical mechanism that allows dry chemical powders contacting with water at the target point. A small permanent magnet is utilized to separate reagents and wet paper before drug injection. It is designed to be stable during locomotion by virtue of the attractive force of a big permanent magnet. To trigger releasing mechanism, gradient magnetic field from EMA system is created to push small magnet slide down, which allows reagents drop and contact with water in wet paper. The designed DDM has length of 11 mm and diameter of 11 mm. The proposed robotic capsule could show high potentials to be utilized for therapeutic treatment of digestive diseases in practical clinical sites through simulation and ex-vivo experiments.