Nanocomposites and Nanomaterials

Synthesis of CeO2 Nanoparticles and Study of Their Biocompatibility and Bioactivity 
K. Siposova1, A. Musatov1, V. Huntosova2, L. Lenkavska3, Yu. Shlapa4, S. Solopan4 and A. Belous4

1Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 040 01 Kosice, Slovakia
2Center for Interdisciplinary Biosciences, Technology and innovation park, P.J. Safarik University in Kosice, Jesenna 5, 041 54 Kosice, Slovakia
3Department of Biophysics, Faculty of Science, P. J. Safarik University in Kosice, Jesenna 5, 041 54 Kosice, Slovakia
4V. I. Vernadskii Institute of General and Inorganic Chemistry of the NAS of Ukraine, 32/34 Prospect Palladina, Kyiv, 03142, Ukraine

Cerium oxide nanoparticles (CeO2-NPs) may exhibit antioxidant activities when they have size of several nm, therefore they are of particular interest for biomedical application, e.g. in therapy of some neurodegenerative diseases [1]. The aim of this study is synthesis of small CeO2-NPs by precipitation from reversal microemulsions and analyze the impact of NPs on biocompatibility and oxidative stress of the U87 MG cells line.
It has been shown that synthesized CeO2-NPs are single-phased and have crystalline structure after synthesis. According to DLS and TEM data, NPs are non-agglomerated with average size 5-6 nm (±1 nm). It was shown that such NPs are positive-charged (ζ=+46.9 mV) and demonstrate high stability in aqueous suspension. 
MTT-assay has showed high biocompatibility of CeO2-NPs with U87 MG cells during 48 h, NPs are mostly localized in the perinuclear area. It was detected that nanoparticles presence in the cell culture medium did not significantly influence mitochondria membrane potential. While MTO (MitoTracker® Orange CMTM/Ros) fluorescence intensity measurement did not reveal ROS, MTO fluorescence lifetime images demonstrated higher stress induced by ROS in mitochondria localized close to the nucleus.

1.	Estevez A. Y., Erlichman J. C. The potential of cerium oxide nanoparticles (nanoceria) for neurodegenerative disease therapy // Nanomedicine.-2014.- 9.- P. 1437–1440.