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modulus matching neural tissue and Pt nanocluster-coated tips for enhanced signal fidelity, enable chronic
recording of intra-organoid signals across customizable 3D coordinates. A key innovation is magnetic
reshaping via ferromagnetic cobalt layers, allowing single electrodes to tilt up to 51.6° and cover 891 times
larger detection areas (6.994 × 10 μm ) for multi-spot neural mapping without physical electrode additions.
2
4
Additionally, a polyvinyl alcohol (PVA)/LM (GaInSn-Ni) composite hydrogel was presented that integrates
stretchability (> 800% strain), rapid autonomous self-healing via hydrogen bonds and LM fusion, and
magnetic field-guided mobility [Figure 14D] . When deployed as wearable sensors for motion and health
[131]
monitoring, the LM hydrogel demonstrates remarkable sensitivity to finger bending and wrist flexion,
producing stable and reproducible current-time curves that correlate precisely with joint angle. Magnetic
responsiveness adds another dimension to its sensing versatility, allowing remote repositioning of sensor
elements through applied magnetic fields, which could enable adaptive sensor networks for dynamic motion
capture scenarios.

CONCLUSIONS AND OUTLOOK
LMs exhibit comprehensive advantages, such as fluidic deformability, high metallic electrical/thermal
conductivity, and facile processability, making them highly promising for applications in soft robotics.
Magnetic manipulation of LMs presents a highly attractive approach for soft robotics due to its non-contact
nature, high spatial precision, and compatibility with diverse environments. A substantial body of related
work has emerged, significantly advancing the development of this field. Here, we present a comprehensive
summary of magnetically manipulated LM-based soft robots, including their fabrication, mechanisms, and
applications. We commence with the preparation methods for MLMs and patterning methods for LMs.
Then, the mechanisms of magnet manipulation (via permanent magnets or electromagnets) and Lorentz
force manipulation are discussed, along with auxiliary manipulation methods utilizing other physical fields,
such as electric fields. Finally, we demonstrate the applications of the four types of magnetically manipulated
LM-based soft robots (i.e., droplet, slurry, particle, and composite), from flexible electronics to biomedical
engineering.

Our classification framework for LM-based soft robots is based primarily on the functional form, operational
characteristics, and compositional state, rather than rigid distinctions in final material composition. It is
important to note that given the inherent overlap among material states in this emerging field, completely
mutually exclusive categories are difficult to establish. For instance, a slurry-based robot, while technically a
composite of LM and magnetic particles, is categorized based on its key operational behaviors originating
from slurry-like rheology and flow characteristics. Similarly, a composite-based robot might be fabricated by
mixing LM slurry with an elastomer, but its final classification is determined by its solid-state functional
form. This type-oriented framework could offer a clear and practical method to organize and understand the
diverse array of representative systems currently under development. To provide a comprehensive overview
of the proposed classification framework, Table 2 summarizes the distinct compositions, key characteristics,
and representative applications of these four types. Despite remarkable advances, persisting challenges stand
as both obstacles and opportunities, demanding urgent solutions to propel this field forward.

Material optimization
Although MLMs can be effectively prepared via mechanical or chemical methods, concerns remain
regarding their structural and performance stability. In mechanical mixing, repeated rupture and
reformation of the native oxide layer on LM surfaces facilitate the incorporation of magnetic particles [61,64] .
However, excessive oxide formation can increase the viscosity of the MLMs and compromise their electrical
conductivity. Under harsh conditions, such as strong NaOH solutions, degradation of the oxide layer can
lead to the detachment of particles from the LM matrix . Conversely, chemical approaches such as reactive
[64]
wetting can suppress oxidation. Yet prolonged interfacial contact between the magnetic particles and the LM