s Immunostimulating Activity of Gold-modified Nanodiamond Particles

Background: The fight against infectious diseases includes two main components – immediate direct anti-infective action and stimulation of one's own immunity. Objective: In this study, we investigated the properties of diamond nanoparticles modified with gold. The use of such gold nanoparticles as indirect anti-infectious agents and immunostimulators has certain prospects. Materials and Methods: Gold hydrosols were synthesized by the reduction in an aqueous solution of gold (III) with sodium citrate (Na3Cit) under heating. Modification procedure of nanodiamond by gold requires incubation, a small sample of nanodiamond in a defined volume of a gold sol for about 24 hours in a dark place. We use human blood cells as test objects. The reaction of blastic transformation of lymphocytes was applied here as a test of biological actions of modified nanodiamond. Results: Modified nanodiamond do not have a toxic influence on blood cells. Modified nanodiamond possesses stimulation effects on spontaneous proliferation of lymphocytes and does not significantly affect phytohemagglutinin-induced proliferation. Nanodiamond slightly increases phagocytosis parameters of neutrophil leucocytes. Conclusion: Thus, results showed that the nanodiamond modified by gold possesses immunostimulating activity, increases the phagocytic activity of neutrophilic leukocytes and stimulates lymphocytes in the spontaneous proliferation test. Gold-modified nanodiamond could be considered as a non-direct anti-infective agent through immune stimulation.