Potentiality of the green synthesized silver nanoparticles for heavy metal removal using Laurencia papillosa seaweed

In this study, a simple and eco-friendly approach to biosynthesizing silver nanoparticles (AgNPs), mediated by an aqueous extract of Laurencia papillosa, was successfully developed. The formed nanoparticles (NPs) were characterized by UV-visible spectroscopy, X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), scanning electron microscopy (SEM), and energy dispersive analysis of X-rays (EDAX). The particles showed a crystalline spherical shape with a size ranging from 6.9 to 15.0 nm. By using a central composite design (CCD) based on response surface methodology (RSM), several experimental parameters such as pH, incubation period, and concentration of algal extract were improved. The optimized AgNPs were used as an adsorbent for iron, zinc, manganese, and copper removal from fish aquaculture effluents. The removal percentage was 97.1%, 43.3%, 5.6%, and 2.4% for Fe, Mn, Zn, and Cu respectively. The results imply that AgNPs have the potential to be used as bioadsorbents for heavy metal removal.