Caribbean macro-alga Osmundaria obtusiloba as potential reducer for biosynthesis of metal nanoparticles

M. Cordero-Landrón, L. Adorno-Rivera, A. Ruiz-Mojica, M. Fuentes-Caraballo, E. Fraile, L.M. Díaz-Vázquez
University of Puerto Rico, Rio Piedras Campus,
Puerto Rico

Keywords: Osmundaria obtusiloba, metallic nanoparticle, biosynthesis, macro-algae

Summary:

Marine macro-algae have chemical compounds with greater potential than other aquatic and terrestrial plants for bio-oil and medicine. It has been proposed that terrestrial plant extracts and fungi can work efficiently for the synthesis of metallic nanoparticles (NPs) . In this research endeavor, an innovative biological method was elaborated through the use of Caribbean macro-algae Osmundaria obtusiloba. Algae extracts were used to synthesize gold (Au), silver (Ag), palladium (Pd), and nickel (Ni) NPs. Pd and Ag NPs were biosynthesized at room temperature and Au NPs at 60oC, using Caribbean macro-algae extract as a reducing agent which was added to a 1 mM metallic solution. Ni NPs were biosynthesized at 50o C and added to a 0.111M of NiCl26H2O. UV-Visible spectroscopy was used to monitor the formation of metallic NPs as a function of reaction time. Results revealed that the bio reduction of metal ions in aqueous solution absorbed in the predicted wavelength region and consequent solution color changes were observed. The NPs characterization was determined using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive Spectroscopy (ED, X-ray powder diffraction (XRD) and Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) Spectroscopy. These analyses determined the average particle size and morphology of NPs as well as the identification of biomolecules for capping and efficient stabilization of metallic nanoparticles, respectively. Our work is concentrated in contributing to NPs synthesis via green chemistry methods to improve the use of renewable energy.