Single nanoparticle twists pave the way for medicines on demand: Study

The accurate measurement and characterisation of a single, twisted nanoparticle in a laboratory for the first time has brought the pharmaceutical sector a step closer to produce and blend medicines on a microscopic scale.

The groundbreaking observations were made by physicists at the University of Bath, United Kingdom who measure molecules at the nanoscale, 10,000 times smaller than a pinhead.

The physicists studied the structure of gold and other materials, using a technique called the hyper-Rayleigh scattering optical activity, according to a July 20, 2020 press release from the university.

The technique allowed scientists to see a clear image of a ‘screw thread’ twist in the gold nanoparticle’s shape.

Understanding the chirality — twists within a material — is critical for several industries, including the pharma sector, food additives, perfumes and pesticides.

This is because the direction in which a molecule twists determines some of its properties, said the press release, citing examples.

A molecule that twisted clockwise can produce the smell of lemons, while an anti-clockwise twist or a mirror-image of the lemon-smelling molecule produces the smell of oranges.

“Chirality is one of the most fundamental properties of nature,” said Ventsislav Valev, who headed the project and is a professor at Bath University.

“It exists in sub-atomic particles, in molecules (DNA, proteins), in organs (the heart, the brain), in bio-materials (such as seashells), in storm clouds (tornadoes) and in the shape of galaxies (spirals hurling through space),” he added.

There is immense potential for the practical applications of ultra-sensitive chiral sensing. Local pharmacists will now be able to mix substances in a new manner, using minute droplets of active ingredients instead of large beakers.

The ordinary consumer may, in the future, receive medicine in pills that are “mini-labs” rather than receiving them in bottles to be refrigerated, said Valev.

A precise number of micro-droplets will flow through micro-channels upon cracking the pill. This will mix and produce the needed medicine, explained Valev.

“We can now aim to produce microdroplets containing a single chiral nanoparticle, to use as catalysts in chemical reactions,” said PhD student Lukas Ohnoutek, the first author on the paper.

Chiral materials, including machines, can be built up one nanoparticle at a time from the microdroplets in the future, said Valev.

“This is both a record and a milestone in nanotechnology,” he added.