Electromagnetic field intensity triggered micro-biopsy device for active locomotive capsule endoscope

For an active and precise diagnosis, we developed an active locomotive intestinal capsule endoscope (ALICE), which can be wirelessly driven and controlled using an electromagnetic actuation (EMA) system. Since then, there has been a need to develop a biopsy device integrated into ALICE which can take a biopsy sample inside the gastrointestinal tract for a historical analysis of cancer disease. Toward this goal, this paper proposes a smart-triggered biopsy device for the ALICE using a micro-reed switch, where the integrated micro-reed switch is turned on using a strong magnetic field, and the biopsy device mechanism is activated by a micro-reed switch. To execute the biopsy process, first, the ALICE with the biopsy device is driven by an EMA system, where a moderate intensity magnetic field is used for driving the ALICE to reach a target region on the intestinal wall. After that, by increasing the magnetic field above a critical value, the ALICE is pushed hard against the target lesion, the micro-reed switch is turned on, and the biopsy device is triggered. The biopsy process, therefore, is totally wirelessly controlled by the external magnetic field of the EMA system, without an additional controller module. The prototype of the biopsy device, with dimensions of 12 mm in diameter and 5 mm in length, was integrated into the ALICE and the prototype of the ALICE, with the biopsy device having dimensions of 12 mm in diameter and 32 mm in length. The working principle and mechanism of the proposed biopsy device are introduced and the feasibility of ALICE with the biopsy device is demonstrated through in-vitro experiments.