Phyto-mediated synthesis of silver nanoparticles using flower extract of Erythrina indica and evaluation of their biological activities

Abstract

The goal of this research was to investigate the antibacterial, cytotoxic and photocatalytic properties of silver nanoparticles synthesized from Erythrina indica flowers (EIF-AgNPs). The green synthesized EIF-AgNPs were characterized by UV–visible spectroscopy, field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). The UV–visible spectrum of EIF-AgNPs revealed a 420 nm surface plasmon resonance (SPR) peak. The XRD analysis exhibited that the EIF-AgNPs were crystalline in nature. FT-IR revealed that the flower extract has been stabilized with the EIF-AgNPs by a capping agent. Furthermore, electron microscopy indicated that the EIF-AgNPs were spherical in shape and measured 42.3 nm in diameter. The eco-friendly synthesized EIF-AgNPs show potential antibacterial activity against Staphylococcus aureus and Salmonella typhi in a well-diffusion assay. In addition, in-vitro cytotoxicity tests on MCF-7 cell lines demonstrated that EIF-AgNPs (42.5 µg/mL) have harmful effects. Furthermore, EIF-AgNPs had a high degradation efficiency for reactive orange 16 (RO16), with 90 % elimination after 120 min of sunlight irradiation. Overall, the findings of this study indicate that Erythrina indica flower biosynthesized EIF-AgNPs may have antibacterial, cytotoxic and photocatalytic effects.