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Page 12 of 26 Chen et al. Soft Sci. 2026, 6, 3

mechanical and chemical sensing [177-179] . Through magnetoelastic materials and bioadhesive footpads, these
robots exhibit locomotion via crawling or climbing, enabling temporary fixation at the mucosal surface [177] .
Tissue contact driven by magnetic torque allows localized measurements of biomechanical properties such as
detachment forces. Integration of pH-responsive adhesives further enables environmental sensing, which is
useful for detecting ulceration or inflammation-associated acidity. This approach unites physical probing
with biochemical diagnostics in a single system [Figure 2C].

Fluidic magnetic soft robots further expand this paradigm. By embedding magnetic microparticles in
polymeric networks such as poly(vinyl alcohol), reconfigurable slime robots that combine high deformability
with fast response to magnetic fields have been developed . These soft-bodied systems can transform into
[70]
C-shaped or toroidal configurations to encapsulate and retrieve foreign objects, such as accidentally ingested
button batteries. Their high tissue compliance and extensibility reduce mucosal trauma. Additionally,
magnetic soft robots with integrated heating modules have demonstrated potential for remote thermal
therapy [181,185] . Bilayer designs comprising surface-mounted aluminum foil arrays for Joule heating and
underlying magnetic elastomers allow robots to be navigated precisely to the site of interest [181] . Alternating
magnetic fields induce localized heating at clinically relevant temperatures (> 70 °C) for coagulation or
ablation in hemorrhagic lesions [Figure 2D]. This convergence of targeted navigation, adaptive locomotion,
and energy delivery offers a unified approach to minimally invasive treatment.

Urinary and reproductive systems
The urinary and reproductive systems are responsible for essential physiological processes, including urine
storage and excretion, gamete transport, fertilization, and childbirth. These systems feature narrow, tortuous
lumens, such as the ureters and fallopian tubes, often measuring a few millimeters in diameter. They also
exhibit rhythmic contractions that propel fluids and display high wall compliance, allowing substantial
deformation under physiological pressure changes. The mucosa-lined walls are richly vascularized and
densely innervated, making them particularly sensitive to mechanical stress and highly responsive to
irritation or injury. In this environment, small-scale magnetic soft robots have emerged as promising
minimally invasive surgical tools. Their intrinsic compliance and ability to morph their shape allow them to
navigate and conform to confined, curvilinear spaces, minimizing the risk of tissue damage. Meanwhile,
magnetic actuation offers wireless, remote control over their locomotion and functional operations, such as
targeted drug release, tissue sampling, and biofilm disruption.

Recent advances in magnetic soft robots have demonstrated targeted intervention capabilities in the oviduct.
A representative system features magnetic segments interconnected via hyperelastic linkages, with each
segment embedded with photothermal-responsive hydrogels [186] . This design allows localized gel-sol
transitions upon near-infrared stimulation, enabling programmable shape transformation under low-
strength magnetic fields. In ex vivo porcine oviduct models, robots with dynamically transitioned
locomotion modes were navigated through folded, ciliated ducts and executed photothermally triggered drug
release [Figure 3A]. Beyond navigation and delivery, magnetic soft robots have been developed for biofilm
disruption - an unmet clinical need in long-term urinary catheterization [187] . A star-shaped octagram soft
robot, fabricated from silicone elastomer embedded with cobalt nanowires, demonstrates strong shear-force
generation under rotating magnetic fields [Figure 3B]. In urethral catheter models, this motion effectively
dismantled biofilm aggregates without damaging the lumen or requiring chemical agents, offering a
mechanical, minimally invasive solution to catheter-associated infections.

For autonomous biopsy in the upper urinary tract, thermally triggered magnetic microgrippers have
emerged as a novel tool. Fabricated from stress-engineered multilayer films, these devices complete self-
folding into cage-like configurations at body temperature to capture tissue samples and can be retrieved by a
magnet . When delivered via standard ureteral catheters, these microgrippers have demonstrated efficient
[188]