The cytotoxic effects of silver nanoparticles with different surface charge in Jurkat cells
The in vitro biological (including toxic) effects of silver nanoparticles (SNP) depend on the nanoparticle characteristics that determine the SNP interaction with cells and their subsequent behavior in a cell interior. As shown in studies both with SNP and some other nanoparticles, the nanoparticle surface charge plays a role in nanoparticle - cell interaction. To date, however, there is still a lack of systematic studies on the role of surface charge in SNP effects on cells. The aim of this work is to study the cytotoxic effects of SNP with different surface charge using a Jurkat cell line. We prepared two SNP solutions where the particles have the same (spherical) shape and average size (13 nm) but are coated with different stabilizers, aerosol-OT and b-cyclodextrin; hence the nanoparticles possessed different negative zeta potential values, -89,4 mV and -35,6 mV for aerosol-OT and b-cyclodextrin, respectively. After the 24 h treatment of cells with SNP in the concentration range of 0.5-2.5 mg/mL, the cytotoxic effects were estimated by means of 1) MTT assay, 2) apoptosis and necrosis detection by annexin V and propidium iodide, and 3) observation of morphological alterations in cells. Cytotoxicity was detected after incubation with aerosol-OT-stabilized SNP; the toxicity of aerosol-OT itself was also observed. The SNP stabilized b-cyclodextrin did not exert any toxic effects. The results obtained suggest that surface charge and, in some cases, the effects of only stabilizers should be considered as important factors in nanoparticle - cell interactions and should be taken into account in further studies of SNP effects.