Scientists in Singapore have developed a tiny robot about the size of a seed that can perform five different medical tasks inside the body, potentially opening the door to safer and more precise surgeries in the future.
The miniature robot was created by researchers at Nanyang Technological University and measures just 4.4 millimeters long.
Despite its tiny size, the robot can move across soft surfaces, cut tissue, release drugs, collect tissue samples, and generate heat for medical treatments.
Even more impressively, it can switch between these functions in less than one second.
The research, published in Advanced Materials, was led by Lum Guo Zhan, who specializes in soft miniature robotics.
The robot is controlled wirelessly using weak magnetic fields. In laboratory experiments, scientists used magnetic coils to guide the robot and activate its different tools remotely.
For example, the robot could deploy a tiny blade to cut through tissue, release particles that mimic medicine, grip and store tissue samples for biopsy testing, or generate localized heat. The heat-producing function could eventually support magnetic hyperthermia treatments, a method being explored for killing cancer cells using heat.
Miniature medical robots are being studied around the world because they may one day allow doctors to perform procedures deep inside the body without making large surgical cuts. This could reduce pain, shorten recovery time, and improve precision during treatment.
One of the biggest challenges in designing such tiny robots is fitting multiple functions into an extremely small device while still allowing precise control. The NTU team solved this problem by creating a special magnetic control system that can quickly change the robot’s behavior.
The robot is built from soft silicone-based materials called PDMS and Ecoflex, which are flexible and commonly used in soft robotics. Tiny magnetic particles are embedded inside the robot, allowing different sections to respond to magnetic fields in different ways.
At the center of the robot is a magnetic module that can be magnetized and reprogrammed in different directions. Each magnetic orientation activates a different tool or movement.
The researchers also engineered the robot so that only one section reacts to a magnetic field at a time. This is important because most small magnetic robots behave like a single magnet, causing all parts to move together and limiting precision.
The NTU robot also has an additional movement ability known as rolling, allowing it to spin around its own axis. This extra flexibility helps it navigate narrow, uneven spaces similar to those found inside the human body.
In tests using chicken liver tissue and gel materials that imitate soft human tissue, the robot successfully completed all five functions. The materials also appeared highly biocompatible. More than 99% of human skin cells exposed to the robot’s materials survived during laboratory testing, suggesting the materials are largely non-toxic.
The seven-year project is still in the research stage, but the team is now exploring how the robot could work with medical imaging systems and realistic artificial organs. Researchers hope future versions may eventually assist doctors during minimally invasive surgeries and targeted treatments inside the body.
Source: Nanyang Technological University.
