The nanoparticles that can communicate
Life is all about communication. From societies all the way down to organs, tissues, and cells, communication is vital to keeping all the parts working in harmony. Now, researchers at the frontiers of nanotechnology—the fabrication of tiny functional materials—are looking at communication too, as reviewed in the journal Nano today.
“Although the field is in its infancy, there have been some stimulating recent advances,” says Ramón Martínez-Máñez at the Polytechnic University of Valencia, Spain, one of the authors of the review. He points out that “traditional communication technologies cannot be applied nanometrically as transmitters and receivers are still too big to fit on a nanoparticle,” so researchers are turning to small molecules to carry the signals (see image).
One focus of the Martínez-Máñez and co-author Reynaldo Villalonga team is the possibility of nanoparticles that can communicate precisely where drugs are needed in the body. One option is to use a material called mesoporous silica. This can be attached to chemicals that detect when target cells have been found and signal that discovery to neighbouring nanoparticles. The communication could initiate a drug-release cascade that may be more effective than nanoparticles that simply work alone. The team has already demonstrated that this is possible with various proof-of-concept systems.
Other researchers are using biomolecules, including DNA, incorporated into nanoparticles to achieve the basic operations of computational logic. For example, if two specific chemical signals are detected by suitable molecules on a nanoparticle, it can result in a new signal molecule being released to achieve the equivalent of an “AND” logic gate. Other logic gates known as “OR” and “NOT” can generate a signal if only one of two chemical inputs is present, or in the absence of a specific signal. Combining these operations into more interesting computational circuits will require communication between nanoparticles.
The research is currently in the early stages, but Villalonga believes the potential is enormous. “Communication between nanodevices is a very appealing research field for us, and there is much to be explored,” he says. Martínez-Máñez and Villalonga confidently envision a future in which nanorobots will work cooperatively to tackle many currently intractable challenges facing medicine and industry.
