Researchers at Nanyang Technological University (NTU) in Singapore have built a soft robot 4.4 mm long that performs five distinct surgical functions and is controlled wirelessly by a weak magnetic field. The work was published on August 10, 2026, in the journal Advanced Materials. It is still lab-stage research, but a rare demonstration of so many functions packed into a single microrobot.
Key takeaways
- 4.4 mm long, controlled wirelessly by a weak magnetic field from external coils.
- Five functions: move, cut tissue, release drugs, grip and store samples, generate heat remotely.
- Switching between functions takes under one second.
- Soft PDMS and Ecoflex silicones embedded with magnetic microparticles about 5 micrometers across.
- Tested in vitro only: chicken liver, gel tissue models, human skin cells (99 percent viability).
Five functions, one body
The robot can move, cut tissue, release drugs, grip and store samples, and generate heat remotely. Switching between these modes takes under a second. The key is a build from soft magnetic materials, the silicones PDMS and Ecoflex, embedded with magnetic microparticles about 5 micrometers across. External coils create a weak magnetic field that changes the robot's shape and behavior with no onboard wires or batteries.
Five functions in one body, switched in under a second:
Magnetism instead of motors
Most magnetic robots like this can perform only one or two functions. Our latest invention can now do five.
— Assoc Prof Lum Guo Zhan, Nanyang Technological University, who led the research.
That is the main difference from earlier magnetic microrobots, which usually stuck to navigation or a single task. The soft build lets one device take on different shapes and roles instead of inserting separate instruments. Having no rigid actuators or onboard electronics also simplifies miniaturization.
Lab only, for now
The robot was tested in vitro?in vitro: Testing outside a living organism — on tissue models or cell cultures, not in animals or humans. only, outside a living body. Trials used chicken liver, gel-based soft-tissue models, and cultured human skin cells. After contact with the robot, 99 percent of the skin cells stayed alive, which the team offers as an early sign of low invasiveness. That is not the same as animal or human studies, and the path to clinical use is long.
Why it matters
Minimally invasive surgery has long aimed to do as much as possible with a single inserted tool. The NTU robot shows that a soft, magnetic build can combine navigation, cutting, drug delivery, sample collection, and heating in one body smaller than a grain of rice. Fewer instrument swaps mean a potentially shorter and safer procedure. The work fits a broader push in magnetically steered microrobots, where the number of available functions has been the bottleneck. The result stays lab-bound, though, and does not yet translate into a ready treatment.
What's next
- The next step is in vivo testing in animal models, since the robot has so far been tested only in the lab, outside a living body.
- Precise navigation and control deep inside the body, beyond the reach of laboratory magnetic coils, remains an open challenge.
Sources
- Robohub — A '5-in-1' Seed-Sized Surgical Robot
- Advanced Materials — Miniature Soft Robot With Magnetically Reprogrammable Surgical Functions
