A quantitative in vitro approach to study the intracellular fate of gold nanoparticles: from synthesis to cytotoxicity

Abstract

Due to their physico-chemical characteristics, gold nanoparticles (AuNPs) seem to be suitable for biomedical and therapeutic applications even if conflicting data on their toxicological profiles are present in literature. In order to better understand if AuNPs could be safe we must consider different biological endpoints such as cytotoxicity, genotoxicity, inflammation and biopersistence. Starting from these considerations, one of the first issues to be assessed is to better understand if AuNPs can be internalized by cells. In this work, we propose a methodological approach to radioactivate AuNPs by neutron activation and the quantification of their internalization by two in vitro cell systems such as MDCK and HepG2 after 24 h of exposure. Despite a dose-dependent internalization, no evidence of cytotoxicity, determined by two different standard in vitro methods such as Neutral Red Uptake and Colony Forming Efficiency, was observed.

Keywords::

• Gold nanoparticles
• neutron irradiation
• in vitro systems
• uptake
• intracellular distribution

Acknowledgements

This work is supported by STREP project CellNanoTox (FP6-2004-NMP-TI-4- 032731) financed by the European Commission. The authors thank Dr Daniele Bonacchi and Dr Giada Lorenzi for the synthesis of gold nanoparticles, Mrs Marianne Mueller, Mrs Luise Meyer and Mrs Karin Molter for the TEM pictures.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.