A little teamwork might help Laguna Design/Science Photo Library

Two nanoparticles have communicated with one another to perform a task for the first time, paving the way for more complex nanomachines that could be useful in areas such as cancer treatment.

Researchers have been able to manipulate individual atoms for years, but creating useful devices at the nanometre scale has remained a challenge. It’s difficult to make tiny motors and batteries interact in any meaningful way because traditional communication technologies require relatively large and power-guzzling parts.

No nanoparticle is an island, though: without communication, they cannot do anything more complicated than the most basic energy conversion or storage.


“A nanomachine by itself cannot do much,” says Josep Miquel Jornet of the University at Buffalo in New York. “Just like you can do many more things if you connect your computer to the internet, nanomachines will be able to do many, many more things if they are able to interact.”

Call and response

Looking to nature was key to solving this problem. Cells and bacteria use chemical signals to communicate, so Reynaldo Villalonga at the Complutense University of Madrid in Spain and his colleagues aimed to make artificial nanoparticles do the same.

The team used a pair of specially prepared Janus particles, so-called because like the ancient Roman god Janus, they have two faces. One face of each was made of porous silica to carry the particle’s cargo – in this case, dye ­– and the other of gold. The gold faces, which handled the communication, were specially treated with different enzymes that respond to signals from one another.

When the gold face of the first particle was exposed to a molecule of lactose, it broke down the molecule and released glucose, which the gold face of the second particle transformed into acid. Triggered by the acid, the second particle’s silica face released an amino acid back to the first, which recognised that compound and released the final product, a dye.

The dye is only released if every step of the communication process goes as planned. If this happens, it therefore indicates that the nanoparticles successfully sent messages back and forth.

Tiny robots

“It seems simple, but this is happening between machines that are tens of nanometres across,” says Jornet. This two-way communication is crucial for more complicated machines and networks on the nanometre scale.

“This is one of the first steps toward constructing a nanosized robot,” says Villalonga. “Our dream is to construct an autonomous nanomachine that can be used to fight cancers.” If the final product of the interaction was medication rather than dye, such a machine could be used to precisely target cancer cells and only release medication when the cells began to become malignant.

The system will still require a few tweaks before it’s ready to be tested inside the human body, but Jornet says it’s a promising advance towards disease detection and treatment on the scale of single cells.

The next step, says Villalonga, is to create communicating networks of several particles to perform more complex tasks that could have applications in both biosensing and computing.

Journal reference: Nature Communications, DOI: 10.1038/ncomms15511

Read more: https://www.newscientist.com/article/in64-instant-expert-nanotechnology/