Synthesis and analysis of silver-copper alloy nanoparticles of different ratios manifest anticancer activity in breast cancer cells

Background Breast cancer is therapeutically very challenging to treat as it has the main four known genetic alterations, which result in the existence of several phenotypes leading to the difference in the mode of therapy and with poor outcome. Metallic nanoparticles of silver or copper have been studied previously as anticancer agents in breast cancer and other types of cancers. However, the anticancer effect of silver-copper alloy nanoparticles (AgCu-NP) is not studied in breast cancer. In this study, we aim to synthesize silver nanoparticles (Ag-NP), or copper nanoparticles (Cu-NP), and AgCu-NP and evaluate their toxicity in breast cancer and healthy breast cells. Results We synthesized sodium citrate and mercapto-propionic acid (MPA-3) capped water-soluble metallic nanoparticles of Ag-NP or Cu-NP and an alloy of three different combinations of AgCu-NP. High-resolution transmission electron microscopy characterization of nanoparticles revealed the spherical shape nanoparticles of varied sizes, furthermore dynamic light scattering characterization was performed, which investigated the hydrodynamic size and stability in phosphate buffer solution. Energy-dispersive X-ray spectroscopy (EDS) measurements were obtained from the transmission electron microscope to study the composition of alloy nanoparticles and the distribution pattern of silver and copper in the alloy nanoparticles. We measured the toxicity of nanoparticles to breast cancer MCF-7 cell line by MTT assay and compared the toxic effect with non-cancerous breast epithelial cells MCF-10A. Our data showed that Ag-NP or Cu-NP have no effect on cancer cells or healthy cells, except Ag-NP at 20 mu g/ml were toxic to cancer cells. However, AgCu-NP were significantly toxic to MCF-7 cells at 10 mu g/ml concentration, while as AgCu-NP have no toxic effect on healthy cells. Furthermore, we observed the cell death pathway by the apoptosis marker Annexin-V which showed non-significant results, while the exposure of AgCu-NP in MCF-7 cells leads to toxicity and also caused significant increase in MMP-9 level, which suggests the cell death may be associated with other pathways such as autophagy and oxidative stress related. Conclusion The data suggest that the AgCu-NP alloy imposes preferential toxicity in breast cancer MCF-7 cells and thus could be exploited as a new candidate for further anticancer investigation