Primeiro registro de nanopartículas metálicas produzidas por algas em sistemas naturais

Abstract

Nanotechnology is defined as the development, synthesis, characterization and application of materials with nanometric dimensions, called nanomaterials and is a concept related to nanoscience, which corresponds to the study of structures and molecules with dimensions between 1 and 100 nm. Recently, there has been an increase in interest in nanotechnology, as nanomaterials can be useful in a variety of human activities, including catalytic applications in many industrial processes, biofuel and electronics production, water purification, medicinal uses, and biotechnology applications generally. The key elements for nanotechnology are nanomaterials, which can have different shapes, such as nanorods, nanoparticles or nanosheets, and which can be characterized based on their dimensionality. Nanoparticles (NPs) have a size that varies from 1 to 100 nanometers, a single dimension and can be composed only of carbon atoms, this element in the form of organic matter, metals or metallic oxides. More specifically, metallic nanoparticles (MeNPs) are synthesized from metallic precursors, the use of some reducing agent and organic ligands that stabilize the NP structure, and can also function as reducers. There are three main types of approaches for the synthesis of NPs: physical, chemical and biological. The physical approach, also called Top-Down, uses physical processes to reduce structures to the nanometer scale, while the chemical and biological approaches are construction processes known as Bottom- up, starting from the atomic scale to the nanometer scale. In the present work, the Green Synthesis method was used to obtain metallic nanoparticles, made by microalgae, eukaryotic organisms, uni or multicellular, capable of carrying out the photosynthesis process. Conventional synthesis methods can be environmentally harmful, expensive and require high energy costs to carry out. The results obtained by specialized microscopy techniques showed the presence of MeNPs formed by various chemical elements, what it may indicate the composition of the soil and the affinity of microalgae in the area for these chemical elements. There are no academic records of the biosynthesis process of MeNPs by microalgae occurring in nature, therefore, this work aims to detect the occurrence of this process in a natural environment.