Gold nanoparticles synthesis and biological activity estimation in vitro and in vivo.

UNLABELLED: The aim of the work was the synthesis of gold nanoparticles (GNP) of different sizes and the estimation of their biological activity in vitro and in vivo. MATERIALS AND METHODS: Water dispersions of gold nanoparticles of different sizes have been synthesized by Davis method and characterized by laser-correlation spectroscopy and transmission electron microscopy methods. The GNP interaction with tumor cells has been visualized by confocal microscopy method. The enzyme activity was determined by standard biochemical methods. GNP distribution and content in organs and tissues have been determined via atomic-absorption spectrometry method; genotoxic influence has been estimated by "Comet-assay" method. RESULTS: The GNP size-dependent accumulation in cultured U937 tumor cells and their ability to modulate U937 cell membrane Na(+),K(+)-АТР-ase activity value has been revealed in vitro. Using in vivo model of Guerin carcinoma it has been shown that GNP possess high affinity to tumor cells. CONCLUSIONS: Our results indicate the perspectives of use of the synthesized GNP water dispersions for cancer diagnostics and treatment. It's necessary to take into account a size-dependent biosafety level of nanoparticles.

The use of nanoferromagnetics to increase the cytotoxic effect of antitumor drugs.

AIM: To investigate the influence of ferromagnetic nanoparticles on antitumor effect of doxorubicin and mitochondria oxidative phosphorylation. METHODS: The study was carried out on the mice-hybrids (C57Bl/6xDBA/2) with intraperitoneally (i/p) transplantated Ehrlich ascitic carcinoma. Single i/p injection of doxorubicin (Dox), stabilized ferromagnetic nanoparticles (Fe3O4; 20-40 nm; FM) or their combination were performed 7 days after tumor transplantation. The cytotoxic effect of agents, morphology and cell cycle of tumor cells were studied 24, 48 and 72 h after Dox administration. RESULTS: The investigations showed that ferromagnetic nanoparticles increased the cytotoxic effect of doxorubicin on Ehrlich ascsmall i, Ukrainiantic carcinoma mainly 48 h after agents' administration. The largest number of apoptotic cells was observed in group of animals in which doxorubicin was administered before ferromagnetic nanoparticles. Moreover, the ferromagnetic nanoparticles at concentration 1.45 microg Fe/ml and, particularly, 7.25 microg Fe/ml decreased mitochondria oxygen consumption in phosphorylation state that may negatively influence their living capability. CONCLUSIONS: Obtained data point out the perspective of use of certain sized FM nanoparticles to increase the cytotoixc effect of antitumor drugs.