Montag, 14. Oktober 2013, 16:30 - 18:00 iCal
Aktuelle Themen in den Umweltgeowissenschaften III
Dr. Denise Mitrano (EMPA)
"Nanometrology techniques for the characterization of nanomaterials in complex media"
Eberhard Clar-Saal (2B 204)
Althanstrasse 14, UZA II, 1090 Wien
Seminar, Workshop, Kurs
Methods to detect, quantify, and characterize engineered nanoparticles (ENPs) in environmental matrices underpin the ability to elucidate the potential health and environmental risks associated with ENPs. More specifically, techniques are needed to determine the size and concentration of ENPs in a variety of complex matrices at environmentally and toxicologically relevant concentrations. Single particle (sp)ICP-MS and asymmetrical flow field flow fractionation (AF4)-ICP-MS offer substantial advantages for detecting ENPs in assessing many particle characteristics over traditional analysis techniques which require higher concentrations (DLS, UV/Vis, nanoparticle tracking analysis, ion selective electrode) and/or suffer from artifacts of sample preparation (TEM). The development and applicability of these techniques for ENP analysis will be discussed with respect to: (A) ENP size and concentration detection limits, (B) ENP size resolution and (C) multi-form elemental analysis. Although AF4-ICP-MS is sensitive in size fractionating ENPs as small as 2 nm at low ug/L levels, the spICP-MS has superior ENP concentration detection limit (low ng/L) in addition to unique features, such as co-detection of ENP and dissolved M+. Examples of how these techniques can be used to access particle transformation over time in biological and environmental samples are provided, with specific focus on the dissolution of Ag ENPs in natural systems. Here, dissolution rate constants were derived for ENPs of various size and capping agents (60 and 100nm, citrate, tannic acid, and polyvinylpyrrolidone) in laboratory, natural, and processed waters. Water chemistry significantly affected the stability of the particles, ranging from near complete dissolution in tap water within several hours to significant particle persistence in waters containing dissolved organic matter. Lastly, a brief discussion of the utility of spICP-MS and AF4-ICP-MS for characterization of ENP in other applications (e.g. ENP release from products, ENP biological uptake, detection of carbon nanotubes) will be presented.
Veranstalter
Umweltgeowissenschaften, Universität Wien
Um Anmeldung wird gebeten
Kontakt
Andreas Gondikas
Universität Wien
Umweltgeowissenschaften
0043 1 4277 53371
andreas.gondikas@univie.ac.at
Erstellt am Montag, 07. Oktober 2013, 10:55
Letzte Änderung am Freitag, 11. Oktober 2013, 09:21