Direct Ion-Beam Activation of Nanoparticles

Abstract

Tracing nanoparticles is not a simple matter. In many environments detection of their presence using compositional determination is severely limited due to background levels of their atomic constituents, so that only relatively large concentrations can be detected. In addition, it is sometimes necessary to also determine whether the nanoparticles are actually still in particulate form. For low concentrations this may be particularly challenging since structural analysis techniques such as X-ray diffraction or some spectroscopic methods generally lack the sensitivity required at low concentrations, and electron microscopy determination of nanoparticle concentrations in large samples is difficult, expensive, time consuming and may be prone to errors. This chapter covers the area of direct ion-beam activation of nanoparticles (NPs), a method that has been studied and optimised over several years, and which can be used to radiolabel certain types of dry nanoparticulate powders to useful activity levels without significant modification of the nanoparticle properties. If the radiolabels are stably incorporated into the nanoparticles this methods is by far the most sensitive and quantitative available for tracing of very small nanoparticle concentrations.JRC.I.4-Nanobioscience