Synthesis, identification of possible reductants and the mechanism of synthesis of silver nanoparticles for their beneficial effects on human health and his environment

Silver nanoparticles (AgNPs) synthesized using biological means are considered to be effective antibacterial and cytotoxic agents as they possess unique physical and chemical properties. Because of the morbidity and mortality associated with the evolution of microorganisms, microbial infections are considered as a serious concern that needs to be addressed. Considering this issue, AgNPs were synthesized using Phyllanthus niruri leaf extract and characterized using UV-Visible spectroscopy (UV-Vis), field-emission transmission electron microscopy (FETEM), selected area electron diffraction (SAED), X-ray diffraction (XRD) and dynamic light scattering (DLS). The possible reducing agents were elucidated by fourier-transform infrared (FTIR) spectroscopy and liquid chromatography-mass spectrometry (LC-MS). The synthesized nanoparticles were tested for their antibacterial efficacy against the oncogenic pathogens Eggerthella lenta and Escherichia coli that can promote colorectal cancer (CRC). By assessing the levels of BOD, COD and coliforms before and after treatment with AgNPs, it was evident that the synthesized nanomaterials were effective in management of household wastewater. The results of this study indicate that AgNPs were effective in antibacterial effect against oncogenic bacteria and were effective in cytotoxic effects against HCT-15 CRC cells. Subsequently, the AgNPs were less toxic towards L929 normal fibroblasts in comparison to the cancerous HCT-15 cells and are therefore effectively safe for tumor-targeting. This research concludes that the synthesized AgNPs were effective and safe for targeting CRC and treating opportunistic infections related to the malignant condition. Further research at preclinical and clinical levels is warranted to determine the therapeutic benefits of the materials at the nanoscale on other cancer types.