Intracellular imaging of nanoparticles: is it an elemental mistake to believe what you see?

Brandenberger, Christina; Clift, Martin J D; Vanhecke, Dimitri; Mühlfeld, Christian; Stone, Vicki; Gehr, Peter; Rothen-Rutishauser, Barbara (2010). Intracellular imaging of nanoparticles: is it an elemental mistake to believe what you see? Particle and fibre toxicology, 7, p. 15. London: BioMed Central 10.1186/1743-8977-7-15

[img]
Preview
Text
1743-8977-7-15.pdf - Published Version
Available under License Creative Commons: Attribution (CC-BY).

Download (3MB) | Preview

In order to understand how nanoparticles (NPs <100 nm) interact with cellular systems, potentially causing adverse effects, it is important to be able to detect and localize them within cells. Due to the small size of NPs, transmission electron microscopy (TEM) is an appropriate technique to use for visualizing NPs inside cells, since light microscopy fails to resolve them at a single particle level. However, the presence of other cellular and non-cellular nano-sized structures in TEM cell samples, which may resemble NPs in size, morphology and electron density, can obstruct the precise intracellular identification of NPs. Therefore, elemental analysis is recommended to confirm the presence of NPs inside the cell. The present study highlights the necessity to perform elemental analysis, specifically energy filtering TEM, to confirm intracellular NP localization using the example of quantum dots (QDs). Recently, QDs have gained increased attention due to their fluorescent characteristics, and possible applications for biomedical imaging have been suggested. Nevertheless, potential adverse effects cannot be excluded and some studies point to a correlation between intracellular particle localization and toxic effects. J774.A1 murine macrophage-like cells were exposed to NH2 polyethylene (PEG) QDs and elemental co-localization analysis of two elements present in the QDs (sulfur and cadmium) was performed on putative intracellular QDs with electron spectroscopic imaging (ESI). Both elements were shown on a single particle level and QDs were confirmed to be located inside intracellular vesicles. Nevertheless, ESI analysis showed that not all nano-sized structures, initially identified as QDs, were confirmed. This observation emphasizes the necessity to perform elemental analysis when investigating intracellular NP localization using TEM.

Item Type:

Journal Article (Original Article)

Division/Institute:

04 Faculty of Medicine > Pre-clinic Human Medicine > Institute of Anatomy > Topographical and Clinical Anatomy
04 Faculty of Medicine > Pre-clinic Human Medicine > Institute of Anatomy

UniBE Contributor:

Rothen-Rutishauser, Barbara; Clift, Martin and Gehr, Peter

ISSN:

1743-8977

Publisher:

BioMed Central

Language:

English

Submitter:

Factscience Import

Date Deposited:

04 Oct 2013 14:09

Last Modified:

24 Jan 2015 10:29

Publisher DOI:

10.1186/1743-8977-7-15

PubMed ID:

20525241

Web of Science ID:

000280280400001

BORIS DOI:

10.7892/boris.1033

URI:

https://boris.unibe.ch/id/eprint/1033 (FactScience: 201729)

Actions (login required)

Edit item Edit item
Provide Feedback