Avaliação dos efeitos das nanopartículas de prata de diferentes dimensões em células meristemáticas de Allium cepa e Vicia faba

Abstract

Although the effects of silver nanoparticles have already been evaluated in some studies, more data are needed on the adverse effects in biological models, considering the increasing use of these substances and consequent release into the environment. In this context, the objective of this work was to evaluate the cytotoxic and genotoxic effect of silver nanoparticles in different dimensions on meristematic cells of Allium cepa and Vicia faba. Allium cepa and Vicia faba seeds were exposed to different sizes of silver NPs 5, 25, 50 and 75 nm at predetermined concentrations of 100 mg / L and germinated at 24 o C for 24 h. Negative control (distilled water) were subjected to the same conditions. The following parameters were evaluated: mitotic index (MI), nuclear abnormality index (NAI) and micronucleus index (MNI). Statistical analyzes were carried out in the software Origin 8.5 using E. student test (significance level 5%). The results showed that the smaller the size of the silver NPs, the greater the reduction of the mitotic index (MI) in the meristematic cells of A. cepa and V. faba. We also observed genotoxic and mutagenic effects of silver NPs, where a significant difference of BMI and NAI was observed in all dimensions. In this way, these smaller nanoparticles cause greater damages in the plant cells, promoting changes in the ADN.