Biogenic synthesis of Copper nanoparticles using aquatic pteridophyte Marsilea quadrifolia Linn. rhizome and its antibacterial activity

The spread of contagious diseases and the increase in the drug resistance amongst pathogens has enforced the researchers to synthesize biologically active nanoparticles. Development of eco-friendly practice for the synthesis of nanoparticles is growing bit by bit in the field of nano-biotechnology. The present investigation outlines the development of a method to biosynthesize copper nanoparticles (CuNPs) by mixing copper chloride solution with aqueous rhizome extract of Marsilea quadrifolia.  The synthesized nanoparticles were characterized by using the UV-vis spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Atomic Force Microscope (AFM). The UV-vis spectra showed an absorption band at 324 nm. The FTIR measurement revealed the presence of all functional groups having control over reduction and stabilization of the nanoparticles. The SEM micrograph depicts the morphology of biogenically synthesized CuNPs with leaf like structure. The X- ray diffraction pattern confirmed the formation of crystalline nature of CuNPs with an average size of 25.20 nm. Regular gravel like structure of CuNPs was displayed in the AFM image. Additionally, the biosynthesized CuNPs were found to be extremely toxic against two gram positive bacterial strains Bacillus thuringiensis and Streptococcus faecalis.