Magnetic nanoparticles of Ni/NiO nanostructured in film form synthesized by dead organic matrix of yeast

An innovative sustainable protocol of nanobiotechnology has been developed to synthesize Ni/NiO magnetic nanoparticles, nanostructured in film form, through a dead organic matrix of the yeast Rhodotorula mucilaginosa, which was isolated from the Amazon region. It is a synergistic strategy that utilizes green technology, thus minimizing environmental impact and reducing costs. The best conditions for the adsorption of the metal through the dead organic matrix and subsequent synthesis of the nanoparticles were monitored by analyzing the biosorption of nickel by the yeast. The structural characteristics of the film-forming nanoparticles were investigated via high-resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and infrared spectroscopy (FTIR). The magnetic properties of the nanoparticles produced by the dead organic matrix were determined in a superconducting quantum interference device (SQUID). Results indicate that the Ni/NiO nanoparticles are mainly spherical, with an average size of 5.5 nm, present magnetic properties, synthesized extracellularly and involve the proteins of the yeast, which probably confer organization in the film form. Such natural bioprocess suggests a rational protocol strategy as a template for the industrial-scale synthesis of magnetic nanoparticles of metals from the dead organic matrix of yeast and also provides a possible green system of nanobioremediation of metals from wastewater.