Asymmetrical Flow-Field-Flow Fractionation coupled with inductively coupled plasma mass spectrometry for the analysis of gold nanoparticles in the presence of natural nanoparticles

Boris Meisterjahn; Elisabeth Neubauer; Frank Von der Kammer; Dieter Hennecke; Thilo Hofmann

doi:10.1016/j.chroma.2014.10.093

Asymmetrical Flow-Field-Flow Fractionation coupled with inductively coupled plasma mass spectrometry for the analysis of gold nanoparticles in the presence of natural nanoparticles

J Chromatogr A. 2014 Dec 12:1372C:204-211. doi: 10.1016/j.chroma.2014.10.093. Epub 2014 Nov 3.

Authors

Boris Meisterjahn¹, Elisabeth Neubauer², Frank Von der Kammer³, Dieter Hennecke⁴, Thilo Hofmann⁵

Affiliations

¹ Department of Environmental Geosciences, University of Vienna, Althanstr. 14 UZA II, 1090 Vienna, Austria; Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Auf dem Aberg 1, 57392 Schmallenberg, Germany.
² Department of Environmental Geosciences, University of Vienna, Althanstr. 14 UZA II, 1090 Vienna, Austria.
³ Department of Environmental Geosciences, University of Vienna, Althanstr. 14 UZA II, 1090 Vienna, Austria. Electronic address: frank.kammer@univie.ac.at.
⁴ Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Auf dem Aberg 1, 57392 Schmallenberg, Germany.
⁵ Department of Environmental Geosciences, University of Vienna, Althanstr. 14 UZA II, 1090 Vienna, Austria. Electronic address: thilo.hofmann@univie.ac.at.

PMID: 25465017
DOI: 10.1016/j.chroma.2014.10.093

Abstract

Flow-Field-Flow Fractionation (Flow-FFF), coupled with online detection systems, is one of the most promising tools available for the analysis and characterization of engineered nanoparticles (ENPs) in complex matrices. In order to demonstrate the applicability of Flow-FFF for the detection, quantification, and characterization of engineered gold nanoparticles (AuNPs), model dispersions were prepared containing AuNPs with diameters of 30 or 100nm, natural nanoparticles (NNPs) extracted from a soil sample, and different concentrations of natural organic matter (NOM), which were then used to investigate interactions between the AuNPs and the NNPs. It could be shown that light scattering detection can be used to evaluate the fractionation performance of the pure NNPs, but not the fractionation performance of the mixed samples that also contained AuNPs because of specific interactions between the AuNPs and the laser light. A combination of detectors (i.e. light absorbance and inductively coupled plasma mass spectrometry (ICP-MS)) was found to be useful for differentiating between heteroaggregation and homoaggregation of the nanoparticles (NPs). The addition of NOM to samples containing 30nm AuNPs stabilized the AuNPs without affecting the NP size distribution. However, fractograms for samples with no added NOM showed a change in the size distribution, suggesting interactions between the AuNPs and NNPs. This interpretation was supported by unchanged light absorption wavelengths for the AuNPs. In contrast, results for samples containing 100nm AuNPs were inconclusive with respect to recovery and size distributions because of problems with the separation system that probably related to the size and high density of these nanoparticles, highlighting the need for extensive method optimization strategies, even for nanoparticles of the same material but different sizes.

Keywords: Engineered nanoparticles; Heteroaggregation; Hyphenated field flow fractionation; Natural nanoparticles; Natural organic matter.