Open-close Mechanism of Magnetically Actuated Capsule for Multiple Hemostatic Microneedle Patch Delivery

Recently, various studies on drug delivery and treatment in the gastrointestinal tract using capsule endoscopes have been conducted. In drug delivery and treatment using capsule endoscopy, along with rapid and accurate delivery, protecting the drug while the capsule moves to the lesion site is an important issue. In this paper, we propose a magnetically actuated capsule with an open-close mechanism for the delivery of multi-layer hemostatic microneedle (MN) patches, where the capsule can move to lesion sites via electromagnetic actuation. Through the proposed open-close mechanism, the capsule is closed to protect the MN patches during its locomotion state and is opened to protrude and deliver them to the lesion sites during its delivery state. The open-close mechanism of the capsule was validated through kinetic analysis and actuation tests. In addition, the hemostatic performance of the MN patch was verified through a blood clotting test and platelet adhesion test. Finally, in an ex-vivo test using a porcine small intestine, we demonstrated that the capsule with the open-close mechanism moved to target lesions and successfully delivered MN patches to the targets.