Low cytotoxicity of anisotropic gold nanoparticles coated with lysine on peripheral blood mononuclear cells “in vitro”

•AuNPs-Lys were synthesized by a seed-mediated grow using Lys as a structure and shape directing agent.•AuNPs-Lys were not cytotoxic for PBMC.•AuNPs-Lys evaluated in this research might be safer for biomedical applications.

The aim of this study was to evaluate the cytotoxic effects of anisotropic (non spherical morphologies) gold nanoparticles coated with the amino acid Lysine (Lys) on peripheral blood mononuclear cells (PBMC) “in vitro”. Gold (Au) nanoparticles tested in this study were synthesized by a seed-mediated growth using Lys as a structure and shape directing agent. Cytotoxic effects were evaluated by cell viability (resazurin assay), reactive oxygen species (ROS) induction (2′,7′-dichlorofluorescein diacetate assay), DNA damage (comet assay) and apoptosis/necrosis (Annexin V/propidium iodide assay) after PBMC were exposed to increasing concentrations (10, 25, 50, 100, and 250 μM) of AuNPs coated with Lys (AuNPs-Lys) at different exposure times (3, 6, 12, and 24 h). The results demonstrated that AuNPs-Lys exhibited low cytotoxicity towards PBMC, (high cell viability), with low levels of ROS, DNA damage and apoptosis/necrosis detected after treatment. These data suggest that AuNPs-Lys, might be viable for biomedical application subject to further investigations.