Magnetically Controlled Multifunctional Capsule Robot for Dual-Drug Delivery

This article presents a multifunctional capsule robot (MCR) with active locomotion, dual-drug load, and selective drug release. The MCR has a high ratio of the volume of loaded drug to the total volume of the capsule (RDC) and can provide sufficient dosages for treatment. The MCR might be used to address the limitations in robot-assisted drug delivery, greatly improving the efficiency of intestinal disease treatment. The MCR is composed of a locomotion unit and a drug delivery unit, and these units are controlled by two orthogonal rotating magnetic fields. This proposed MCR enables active locomotion to target positions and selects to release two different drugs according to clinic requirements. In vitro and ex vivo experiments were conducted to evaluate the performance of the MCR. Experimental results show that the maximum drug loading capacity of the MCR is 1.5 g, and the maximum advance and retreat velocities are 11.8 mm/s and 10.4 mm/s, respectively, when the MCR is fully loaded. The MCR can release two different drugs in various targets and no noticeable damages to the pig intestine were observed to the naked eyes. The MCR will have potential further application for intestinal disease treatment.