Cytotoxicity of citrate and PEG coated AgNPs in human liver cells

Abstract

Silver nanoparticles (AgNPs) are increasingly present in industrial and biomedical products, due to their physicochemical and biological properties (efficient antimicrobial activity). There is, however, a growing concern about their possible impact on the environment and the human health. AgNPs are often coated to promote stability and avoid aggregation, however until now there is no complete understanding of the influence of the coating on the toxicity profile of AgNPs. Our study aims to compare the influence of the coating on the toxicity of AgNPs, using the liver hepatocellular carcinoma HepG2 cell line as an in vitro model. Cells were exposed to citrate- and PEG-coated AgNPs of 30 nm, for 24 h, at 5 and 11 μg/mL (concentrations selected based on the IC20 and IC50, respectively) and the effects on cell viability and cell cycle dynamics were analyzed. Results showed that there was an equivalent pronounced reduction in the viability of cells exposed to citrate and PEG coated AgNPs. Moreover, citrate- and PEG-coated AgNPs affected cell cycle progression in a similar way, inducing a delay at S phase and an arrest at G2. In conclusion, our results indicate that the effects of citrate and PEG coated AgNPs on the viability and cell cycle of HepG2 cells are independent of the surface coating.