Nanoparticles by design

Researchers in Japan say they have succeeded in designing and creating multicomponent nanoparticles with controlled shape and structure.

These multicomponent nanoparticles contain two or more materials – in this case silicon and silver – and are even more powerful since they bring together the unique properties of both materials into a single entity with various functionalities.

A team from the Okinawa Institute of Science and Technology (OIST) used advanced equipment custom-designed specifically for producing multicomponent nanoparticles, whose shape and structure can be altered. The researchers say they can also amend the nanoparticles’ characteristics – such as crystallinity. In this particular study, published in Scientific Reports, silver was used to control the crystallinity of silicon. By doing this, the optical, electrical and chemical properties of the nanoparticle can then be fine-tuned.

“This is engineering,” said Professor Mukhles Sowwan, leader of the OIST Nanoparticles by Design Unit. “We control how we want the nanoparticles to be.”

Silver and silicon were also chosen as each has different optical properties which give out different signals. A single nanoparticle capable of sending out multiple signals simultaneously is attractive to the biomedical field because biomolecules such as proteins, antibodies and membrane receptors are all within the size range – 1-100 nm – of these nanoparticles.

These multicomponent nanoparticles may find uses in bioimaging and biosensing. For example, silver would show whether a certain reaction is happening or not, while silicon could help provide information on the particle’s location.

The research team also include scientists from the United Kingdom and Ireland, Greece, India, France, Spain, Peru, South Korea and Palestine.

Inoculation of silicon nanoparticles with silver atoms www.nature.com/srep/2013/131030/srep03083/full/srep03083.html