Twisty nanoparticle breakthrough could pave way to medicines on demand

20 Jul 2020

Image: © GiroScience/

Physicists have found a way to measure a single, twisted nanoparticle in the lab, which could allow for medicines to be blended on a microscopic scale.

Researchers at the University of Bath in the UK have found a way for physicists to ditch a 200-year-old technique to observe nanoparticles, in a breakthrough that could be big news for the pharmaceutical industry.

In a paper published to Nano Letters, the researchers revealed the first accurate measurements of a single, twisted nanoparticle. Understanding the twists in a material – known as its chirality – is vital in industries that produce medicines, perfumes, food additives and pesticides, as the direction in which a molecule twists determines some of its properties.

For example, a limonene molecule that twists clockwise will produce the smell of lemons, while the identical molecule twisting anticlockwise produces the smell of oranges.

Using a new technique called hyper-Rayleigh scattering optical activity, the researchers examined the structure of gold, among other materials, revealing an exceptionally clear image of the ‘screw thread’ twist in the metal’s shape.

The 200-year-old optical method used to determine the chiral properties of molecules and materials, while proven, is weak and requires large amounts of molecules or materials to work. Instead, this latest technique uses powerful laser pulses that can detect a single nanoparticle floating freely in liquid.

‘A milestone in nanotechnology’

“This is both a record and a milestone in nanotechnology,” said Prof Ventsislav Valev, who led the project. “Pursuing this line of research has been one of the most rewarding achievements in my career.”

The potential applications for the discovery are numerous, the researchers said, but could allow local pharmacists to mix substances in a completely new way, producing pharmaceuticals from minute droplets of active ingredients rather than from large beakers of chemicals.

“You’ll be able to go to the chemist with a prescription and instead of receiving a medicine that has to be mixed from bottles of chemicals and then stored in the fridge for several days, you’ll walk away with pills that are mini-labs,” Valev said.

“Upon cracking the pill, a precise number of microdroplets will flow through microchannels to mix and produce the needed medicine.”

In order to do this, the number of molecules and catalysts within each microdroplet needs to be known, which this breakthrough allows for. Valev said that in the future, he imagines the building of chiral materials, and even machines, one nanoparticle at a time using microdroplets.

Colm Gorey was a senior journalist with Silicon Republic