# Combining tethered and untethered magnetic robots via a magnetically triggerable latch for target payload delivery and retrieval

## TL;DR

This paper introduces a magnetic latch system that allows tethered and untethered magnetic robots to work together for precise drug delivery in hard-to-reach body areas.

## Contribution

The novel magnetic latching mechanism enables cooperative operation between tethered and untethered magnetic robots for targeted payload delivery and retrieval.

## Key findings

- A magnetic latch was successfully used to deliver drug-coated, untethered robots in an ex vivo porcine kidney model.
- The system combines the navigational benefits of tethered robots with the miniaturization advantages of untethered robots.
- The approach shows potential for immunosuppressant delivery in organ transplantation scenarios.

## Abstract

The reach and scope of minimally invasive surgical procedures can be transformed via the development of continuum robots. Through soft, flexible structures and accurate navigation, previously inaccessible anatomical regions can be safely reached. Dependent on both actuation mode and clinical application, however, rigidity and miniaturization potential can still present substantial challenges. Magnetic soft continuum robots (mSCRs) offer promising solutions to these key questions. Furthermore, micrometer- to millimeter-scale untethered magnetic robots (mUMRs) offer unparalleled miniaturization potential enabling targeted therapeutic delivery. Leveraging the benefits of magnetic actuation, this study introduces a bespoke, continuously magnetized catheter that synergizes the navigational strengths of mSCRs with the functional effectiveness of mUMRs to precisely deliver drug-doped payloads to otherwise unreachable regions deep within the anatomy. In particular, this system uses a magnetic latching mechanism, ensuring precise drug delivery and efficient retrieval, demonstrated in an ex vivo porcine kidney model for organ transplantation–related immunosuppressant delivery.

A magnetic latch enables tethered magnetic soft robots to deliver and retrieve drug-coated, wireless, small-scale magnetic robots.