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Helium Beam Sifts Molecules

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Scientists have found an exciting new way to manipulate and design new materials at the atomic level, and change the way they behave at a larger scale, opening the way to new applications such as early cancer biomarkers.

They say that the creation of nano “sieves” can help separate molecules down to an unprecedented size 10,000 times finer than a human hair.

“We discovered that a beam of energetic helium ions generated in a helium ion microscope rearranged a nanoporous anodised alumina material on the atomic scale and shrank its pores to various, unprecedented tiny sizes,” said Prof Kostya Ostrikov of Queensland University of Technology. “These tiny pores mean scientists could potentially ‘sift’ molecules into different sizes to study them individually. It could open the way to early detection of cancer, for example, through a blood test that could detect DNA produced by a cancer before the tumour developed.

“This new ion-assisted manipulation of matter on the tiniest of length scales completely changed the behaviour of the aluminium oxide. When we applied moderate exposure to helium ions, its pores shrank. When we increased exposure to the ions, this normally brittle and porous ceramic turned into a superplastic and gained the ability to stretch more than twice without breaking.”

Dr Annalena Wolff said the discovery would allow scientists to...

The full text of this article can be purchased from Informit.