Scientists have created microrobots that can replace medical needles for injections

An international team of researchers from the United States and China has presented a technology that uses the phenomenon of cavitation — the formation and rapid collapse of bubbles in a liquid — to propel microrobots. This is reported by Interesting Engineering with reference to Science materials. The development could become the basis for new methods of administering drugs without the use of medical needles.

The microrobots, called "jumpers," create bubbles by heating a light-absorbing material with a laser. When the bubble reaches a critical size, it collapses abruptly, releasing mechanical energy in the form of a shock wave. This energy can propel the millimeter-sized robots up to 1.5 meters into the air and propel them through the liquid at speeds of about 12 m/s.

The researchers note that the direction, height and force of the jump can be adjusted by changing the intensity, angle and duration of the laser heating. The devices can not only jump, but also slide or "float" in complex environments, including microchannels.

In medicine, such technology will make it possible to deliver drugs through the skin or directly to affected areas, such as tumors, without the use of traditional syringes.

Because the system is based on light heating, it can be configured for minimally invasive procedures. Another advantage of the design is that it does not require an integrated power source or moving parts, unlike microrobots that use magnetic fields or chemical fuels, which are difficult to control inside the body.

Beyond medicine, microrobots can be used to explore hard-to-reach places—in pipelines, mechanisms, or biological systems. In biomedical research, they could potentially work as microswimmers in fluids, such as blood or the intercellular environment.

In addition, the technique may open new prospects for application in cell therapy and high-precision surgery, in cases where standard instruments are too large or not sharp enough.

The technology has great potential, but it is still only at the concept stage. Among the challenges are precisely controlling cavitation in the body without damaging tissue and the limited depth of laser penetration. It is also necessary to investigate the biocompatibility of the materials from which the microrobots are made before conducting tests on living organisms.