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Talks and Poster Presentations (with Proceedings-Entry):

F. Horak, C. Koch, B. Lendl, A. Limbeck:
"Differentiation between dissolved and solid fractions of aqueous nanoparticle suspensions using a Standing-Wave-Separation-Cell in combination with on-line ICP-OES detection";
Poster: 23rd International Symposium on Separation Sciences (ISSS 2017), Wien; 09-19-2017 - 09-22-2017; in: "Book of Abstracts", (2017).



English abstract:
Inductively coupled plasma optical emission spectrometry (ICP-OES) is a well established method for identification and quantification of elements in aqueous sample solutions. Thanks to its robust design and low detection limits it is perfectly suitable for the analysis of suspended nanoparticles. However, regular bulk analysis of these suspensions does not address the possibility of dissolution of particles in the medium. Without combination with a separation technique it is not possible to differentiate between solid nanoparticles and the fraction dissolved in the liquid.
In this work we present a newly developed method enabling on-line separation of nanoparticles from their dissolved fraction in aqueous samples with a dispersed particle extraction (DPE) approach based on a size-dependent switchable filter. Acoustic standing waves are used to exert a trapping force on the µm-sized, surface modified sorbent particles within a commercial flow-through-cell, thus separating them from the rest of the sample suspension and releasing them after it has passed the cell. Commercially available, as well as self-synthesized surface modified particles have been applied on aqueous samples in order to bind the free ionic fraction of selected analytes. The surface modified particles are added to the sample and thoroughly mixed. The suspension is then introduced to the fractionation system, where the surface modified particles are separated from the sample and the fraction of the sample which did not bind to the particles or is unaffected by the separation force passes directly to the ICP-OES. The implementation of this separation cell allows the measurement of both, the dissolved and the solid fraction in an aqueous sample with nanoparticles based on a size-dependent separation in a single measurement and could even be used together with an autosampler device.

Keywords:
disperse particle extraction, particle trap, ultrasonic standing waves, ICP-OES

Created from the Publication Database of the Vienna University of Technology.