Evaluation of Phytotoxicity of Bimetallic Ag/Au Nanoparticles Synthesized Using Geum urbanum L.

Abstract

The growing production and wider application of metal nanoparticles gives rise to many concerns about their release to natural ecosystems. It is very important to be aware of the harmful impact of nanoparticles on living organisms, including plants. Therefore, it is of vital significance to explore the impact of metal nanoparticles on plants. This work assessed the phytotoxicity of bimetallic Ag/Au nanoparticles and Geum urbanum L. extract. The obtained bimetallic Ag/Au nanoparticles were characterized by UV–vis spectrophotometry (UV–vis), Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The microscopic studies enabled the determination of the size of the obtained nanoparticles, which was 50 nm. The wide range of concentrations evaluated in the course of the study made it possible to observe changes in selected plants (seeds of Lepidium sativum, Linum flavum, Zea mays, Solanum lycopersicum var. Cerasiforme and Salvia hispanica-Chia) caused by a stress factor. The studies showed that the solution of Ag/Au nanoparticles was most toxic to flax (IC50 = 9.83 × 10–6/9.25 × 10–6 mg/ml), and least toxic to lupine (IC50 = 1.23 × 10–3/1.16 × 10–3 mg/ml). Moreover, we studied the toxicity of Geum urbanum extract. The extracts diluted to 0.00875 mg/ml stimulated the growth of lupine, flax and garden cress; extracts diluted to 0.175 mg/ml stimulated the growth of Chia and tomatoes; and extracts diluted to 0.00875 mg/ml stimulated the growth of corn. G. urbanum extract was most toxic to lupine (IC50 = 0.374 mg/ml), and least toxic to corn (IC50 = 4.635 mg/ml).