Miniaturized biopsy module using gripper tool for active locomotive capsule endoscope

Abstract Patient-friendly capsule endoscopes with a high-definition camera have gradually become a popular solution to the diagnosis of digestive systems. As a promising method for an active and precise diagnosis, an active locomotive intestinal capsule endoscope (ALICE) with wireless functionality using an electromagnetic actuation (EMA) system has been proposed. For a more precise diagnosis using a capsule endoscope, ALICE needs to have several additional functions, such as biopsy, drug delivery, and tattooing capabilities. Among these additional functions, this paper introduces a miniaturized biopsy module that can be integrated into ALICE. The proposed biopsy module, which uses a gripping tool, can be used to extract biopsy samples from a target lesion in a gastrointestinal organ. First, thanks to a controllable EMA system, along with the biopsy module, ALICE is driven to the target lesion in the intestinal tract using a generated magnetic field. Next, using a strong magnetic field, ALICE can open the gripper blade on its own and closely approach the target lesion. Finally, through the closing of the gripper blade, the biopsy sample can be harvested. The biopsy process is therefore controlled completely wirelessly through the interactions between the permanent magnet inside ALICE and the external magnetic field of the EMA system. A fabricated biopsy module with 13 mm diameter and 5 mm length was successfully integrated into an ALICE prototype 13 mm in diameter and 32 mm in length. Through an in-vitro experiment, we demonstrated the capability of ALICE when combined with the proposed biopsy module, such as its active locomotion and the extraction of a biopsy sample.