Cytotoxicity and genotoxicity of green synthesized silver, gold, and silver/gold bimetallic NPs on BHK-21 cells and human blood lymphocytes using MTT and comet assay

In cancer therapy, nanoparticles (NPs) shall be applied possibly by inoculation in the veins of humans. This action will connect them with white blood cells (WBCs) and red blood cells (RBCs) in the bloodstream before they reach their main targeted cancer cells. However, possible cytotoxicity and genotoxic effects of silver, gold, and silver/gold bimetallic NPs (Ag, Au, and Ag/Au BNPs) on baby hamster kidney-21 (BHK-21) cells and human blood lymphocytes were studied here by comet and MTT assays. Here, Ag, Au, and their Ag/Au BNPs were synthesized by using Hippeastrum hybridum (HH) extract. These NPs were studied by UV-visible spectroscopy, FT-IR, XRD, and EDX, and SEM analysis. XRD analysis conferring the crystal structure with an average size of 13.3, 10.72, and 8.34 nm of Ag, Au, and Ag/Au BNPs, respectively. SEM showed that Ag, Au, and Ag/Au BNPs had irregular morphologies, with nano measures calculated sizes of 40, 30, and 20 nm, respectively. EDX spectrometers confirmed the presence of elemental Ag signal of the AgNPs with 22.75%, Au signal of the AuNPs with 48.08%, Ag signal with 12%, and Au signal with 38.26% of the Ag/Au BNPs. The comet assay revealed that H2O2 and BNPs prompt high rates of DNA damage compared to plant, Ag, Au NPs, and nontreated lymphocytes, which are represented as the total comet score (TCS). The BHK-21cells were incubated in the existence of doxorubicin, plant extract, Ag, Au, and Ag/Au BNPs. The cytotoxic effects could be observed in a dose-dependent mode; doxorubicin and Ag/Au BNPs were more toxic than plant extract, Ag, and Au NPs. It is demonstrated that NPs interact with blood lymphocytes and BHK-21cells, causing significant DNA damage and reducing cell viability in a concentration-dependent manner. However, to reduce the potential threats of NPs, further studies are recommended.