Dentists' tool boost as engineers get to root of tiny bubbles

The physics of how so-called nanobubbles are generated could have a range of clinical and industrial applications, including in dental hygiene devices used to remove plaque, experts say.

The findings could also inform the development of other technologies -- such as devices to selectively target tumour cells -- that harness the energy released when the bubbles burst.

Engineers at the University of Edinburgh ran complex supercomputer simulations to better understand the underlying mechanisms behind the formation of nanobubbles -- which are tens of thousands of times smaller than a pinhead.

The team modelled the movement of individual molecules in a thin layer of water on a surface vibrating a million times faster than the flapping of a hummingbird's wings.

Their analysis revealed that nanobubbles can form either when vibrations cause the water to boil, or when the water pressure drops to a point where liquid becomes vapour -- a process called cavitation.

The study, published in the journal Nano Letters, was supported by the Engineering and Physical Sciences Research Council.

Researchers ran their calculations using the ARCHER UK National Supercomputing Service, which is operated by EPCC, the University's high-performance computing facility.

Saikat Datta, of the University of Edinburgh's School of Engineering, said: "We now have a better understanding of how vibrations at the smallest scale can be exploited to produce nanobubbles. This work has a broad scope for future research and will help researchers devise new experiments to shed further light on the generation of nanobubbles."