Optical and biomedical applications of eco-friendly biosynthesized silver nano spheres using zingiber officinale root extract

Abstract

Abstract Eco-friendly bio-compatible silver nanoparticles (Ag NPs) were successfully synthesized using Zingiber officinale extract in a simple green route at room temperature. The phytoconstituents present in Zingiber officinale (Z. officinale) extract act as reducing and stabilizing agents. The size and crystallinity of spherical Ag NPs were confirmed through transmission electron microscopy (TEM) and X-ray diffraction (XRD) studies. The formation of silver nanoparticles was also confirmed from the UV–vis and FTIR spectra. Luminescence properties of europium (Eu) and samarium (Sm) complexes in the presence of silver were studied. The intensity of luminescence from Eu and Sm complexes were found to get enhanced or quenched with their concentrations in Ag NPs. Interesting nonlinear optical properties exhibited by Ag NPs were observed in the Z-scan experiment suggesting that they can be used as optical limiters for the picosecond (ps) time scale green laser. Silver nanoparticles were tested against colon cancer (HCT116) cells in vitro by MTT assay and they exhibited smaller IC50 values with better inhibition efficiency. Ag NPs induced apoptosis through the activation of Reactive oxygen species (ROS) and Caspase-3 pathways. Antibacterial activity of Ag NPs was analysed against Acinetobacter baumannii (A. baumannii) and Staphylococcus aureus (S. aureus) and they were found to be efficient in inhibiting the bacteria. The results indicate that the biosynthesized eco-friendly nanoparticles having high stability can lead to many applications such as good luminescence enhancement, optical limiting characteristics, anticancerous and antibacterial properties in optics and biomedicine.