Imma Perfetto
Cosmos science journalist
Scientists have created a synthetic material that forms worm-like structures and even moves like them, which could be used for various applications from drug delivery to self-healing materials.
It is part of a new class of materials known as “active matter” that can show incredible life-like behaviour. Unlike inactive matter, which makes up the motionless materials
The material is made of tiny micrometre-sized particles known as Janus colloids, microparticles with hemispheres made of 2 different materials with distinct physical properties.
The researchers suspended the colloids in liquid and applied a strong, oscillating electric field to it. This caused the particles to become polarised, where one hemisphere is negatively charged and the other positive.
Through interactions between these charged dipoles, the scattered particles then assembled to form 3-dimensional worm-like structures.
“We found the formation of fascinating new structures – self-driven active filaments that are reminiscent of living worms,” says Xichen Chao, first author of a paper describing the work in Physical Review Letters.
“We were then able to develop a theoretical framework which enabled us to predict and control the motion of the synthetic worms solely based on their lengths.”
The worm-like chains emerged under low-density conditions. At higher densities, the researchers found the particles formed sheet-like and maze-like structures.
Tannie Liverpool, a professor of theoretical physics at the University of Bristol in the UK and co-author of the paper, says: “…because these materials can move independently, it could eventually lead to the ability to design devices that independently move different parts of themselves, or the design of swarms of particles which can search for a target.”
This could potentially be used in healthcare for targeted medicines and treatments.
But, Liverpool cautions, such “real world” applications are probably far in the future.
The research appears in Physical Review Letters.
