Síntese de nanopartículas de prata mediada por extrato aquoso e etanólico de folhas de Eugenia involucrata: caracterização

Abstract

The different applications of metallic nanoparticles, especially those of silver, have driven the search for methods to obtain nanoparticles in a safer, non-toxic and economical way. In this context, the synthesis of silver nanoparticles mediated by natural products, such as plant extracts, associated with the potential of native plants and biodiversity, has become a trend. The present study aimed to synthesize silver nanoparticles using green synthesis methods, mediated by aqueous and ethanolic extracts from Eugenia involucrata leaves. The extracts were prepared by turbolysis and were evaluated for pH characteristics, phytochemical profile and quantification of phenolic compounds. The synthesis was performed by varying the concentration and pH parameters of extracts in the reaction medium, initially evaluating visual effects on the color change of the medium, monitoring the surface plasmonic resonance band formation by UV-Vis spectrophotometry. The characterization was performed by Fourier transform spectrophotometry and transmission electron microscopy. Both extracts showed similar acidic characteristics and phytochemical profiles, the determination of phenolic compounds proved to be superior in aqueous extracts. As for the synthesis, the results showed that both extracts have compounds that acted as reducing agents of silver ions, and at alkaline pH, the synthesis process was favored, with the formation of smaller diameter silver nanoparticles. This study confirmed the potential of the extractive method and the solvents used to obtain extracts of the species as mediators of the synthesis of silver nanoparticles.