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.

[Influence of gold and silver nanoparticles on ATPase activity of native and rehydrated cells of Escherichia coli].

The expressed changes in the bacteria cells' plasma membrane ATPase activity values cells of Escherichia coli, which are used in the manufacturing of vaccines against cattle colienterotoxemia, have been revealed under the influence of lyophilization/rehydration process. Influence of gold (average size 20, 30, 45 nm) and silver (30 nm) nanoparticles in different concentrations on ATPase activity of native and rehydrated (delyophilized) bacteria cells has been studied. Gold and silver nanoparticles stimulated ATPase activity of native and rehydrated (delyophilizated) cells of the investigated strains. Obtained data show, that application of examined metal nanoparticles of certain sizes and concentrations as protectors and stimulators of main physiological-biochemical properties of production strains' cells under the conditions of lyophilization and long storage stress in technologies of different immunobiological preparations manufacturing is very promising.

[Veterinary probiotic preparation influence on the biochemical blood indices of young farm animals].

The veterinary probiotic preparation was developed on the basis of aerobic part of bacterial strains of normal human intestinal microflora: 3 strains of Escherichia coli--G35No1-413, G35No2-412, G35No3-411, and one Enterococcus faecalis G35No4-410 strain. The influence of a pilot lot of the prepapration on the biochemical blood indices and the state of intestinal microflora of different age groups of young farm animal (calves and piglets) was studied during the process of the commission tests. It has been shown, that the developed probiotic promotes the improvement of protein and mineral metabolism, normalization of level of enzyme activities, which show state of the native immunity of the young farm animals' organism. It was the result of normalization of the intestinal microflora composition. The optimal doses and periods of intake have been determined. On the basis of executed researches the veterinary probiotic preparation has been presented for registration to the State Department of Veterinary Medicine of Ukraine.

[Effect of metal microelements on biochemical indices of probiotic bacteria].

The influence of metal-microelements (Zn, Cu, Ag, Au) in colloid and ionic form on the main biochemical parameters (ATP-ase activity, transmembrane potential and respiratory activity) of E. coli G35 N#1-413 and Ent. faecalis G35 N#4-410 probiont-strains has been studied with the goal to create complex metal-bearing probiotic preparations. Monotonous dose-dependent inhibitory influence of all mentioned metals in ionic form on the bacteria functional activity has been established. Metals' colloids had certainly stimulating influence on microorganisms' biochemical parameters in the same concentration limits with the following maximum positive effects: for Zn - 2x10(-7)-2x10(-4) mg/ml, for Cu - 8.4x10(-7)-8.4x10(-6) microg/ml, for Ag - 23x10(-7)-23x10(-4) microg/ml, for Au - 5x10(-6) microg/ml by metals. It has been shown, that cultural characteristics of probiont-bacteria in the presence of both ionic and colloid forms of studied metals remain stable. Certain stimulation of probiont-bacteria' main enzymes and life-support processes by colloidal forms of the studied metals-microelements in determined concentration and particle dimension limits is the evidence of a possibility of metals' colloids application in probiotic preparations' composition in order to increase the resistance and functional activity of probiont-microorganisms.