'Holy Grail' of particle sizing

Daresbury Analytical Research and Technology Service (Darts), the commercial arm of CCLRC Daresbury Laboratory, has made a groundbreaking discovery in nanoparticle size distribution measurement which it says looks set to revolutionise the rapidly expanding nanopowders market.

Small angle X-ray scattering (Saxs) at Daresbury can now be used to measure the size distribution of true nanoparticles in the 1-100 nanometre range, using specific experimental conditions and advanced data treatment developed on site.

The technique has the flexibility to cope with samples either in liquid suspension or dry powder form, and most importantly can determine particle size distribution - a key requirement of particle size analysis on this scale.

Avecia research manager John Conti-Ramsden applauded the development of this exciting new technology and commented: "Nanoparticles are becoming increasingly important in the development of advanced materials for a variety of industrial applications, and the ability to accurately monitor and control particle size and distribution at these levels is critical".

Powders made up of nanoparticles have application in areas such as controlled-release drug delivery, biotechnology, IT, telecommunications and printing of devices and are used by manufacturers of cosmetics, pigments, clays, prints and catalysts.

In the electronics industry, nanoparticle powders are being used to build up rather than etch out nanostructures.

Until now, the major limiting factor has been the inability to accurately determine nanoparticle size distributions. Traditionally particle size analysis has been performed using light scattering, where the interference patterns from lasers are used to measure nanoparticle size.

Because many nanopowders are smaller than the wavelength of visible light, these methods have a lower limit of 100nm.

The Darts breakthrough now extends measurement capability to orders of magnitude below this limit.