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Investigation of cloud point extraction for the analysis of metal nanoparticles in a soil matrix
Published
Author(s)
Hind El Hadri, Vincent A. Hackley
Abstract
The characterization of manufactured nanoparticles (MNPs) in environmental samples is necessary to assess their behavior, fate and potential toxicity. Several techniques are available, but the limit of detection (LOD) is often too high for environmentally relevant concentrations. Therefore, pre-concentration of MNPs is an important component in the sample preparation step, in order to apply analytical tools with a LOD higher than the ng L-1 level. The objective of this study is to explore the cloud point extraction (CPE) method to pre-concentrate gold nanoparticles (AuNPs) spiked into a soil extract matrix. To that end, different extraction conditions and surface coatings were evaluated in a simple matrix. Then the method was applied to soil extract samples spiked with AuNPs. Total gold determined by inductively coupled plasma mass spectrometry (ICP-MS) following acid digestion yielded a recovery greater than 90 %. Single particle ICP-MS and asymmetric flow field-flow fractionation were also utilized to assess the preservation of size distribution after extraction.
Citation
Royal Society of Chemistry Journal Environmental Science: Nano
El Hadri, H.
and Hackley, V.
(2016),
Investigation of cloud point extraction for the analysis of metal nanoparticles in a soil matrix, Royal Society of Chemistry Journal Environmental Science: Nano, [online], https://doi.org/10.1039/c6en00322b, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=921227
(Accessed October 14, 2025)