Engineers develop injectable micro-robots for drug delivery
Researchers at the University of California, San Diego, have created tiny robots smaller than a millimeter that can be injected into the body to deliver drugs precisely. These micro-robots are powered by ultrasound and could transform treatments for diseases like cancer. The innovation was detailed in a study published on September 28, 2025.
In a breakthrough for medical technology, engineers have invented micro-robots capable of navigating the human body after injection to release medication at targeted sites. The devices, developed over three years by a team led by Professor Sheng Xu at the University of California, San Diego, measure less than one millimeter in length, making them suitable for delivery via standard needles.
The micro-robots consist of a soft, biocompatible polymer body with embedded magnetic particles. Once injected, they are guided by external ultrasound waves, which provide propulsion without the need for onboard batteries. 'This approach allows for non-invasive control and precise localization, potentially reducing side effects from systemic drug administration,' Xu stated in the research paper.
Testing occurred in lab models simulating human tissues, where the robots successfully traveled up to 10 millimeters and released payloads on command. The study, published in Science Advances on September 28, 2025, highlights applications for hard-to-reach areas like the brain or deep tumors. No animal trials were reported in the initial findings.
Background context includes prior work on microrobotics, but this marks the first injectable version powered solely by ultrasound, addressing limitations of earlier tethered or battery-dependent designs. The team notes challenges remain, such as ensuring long-term biocompatibility and scaling production. Implications could include personalized medicine, though clinical trials are years away. This development builds on UCSD's expertise in soft robotics, funded by the National Science Foundation.