IMPACT OF GOLD NANOPARTICLES WITH DIFFERENT COATINGS ON LETTUCE

As one of the widely produced metallic nanoparticles, gold nanoparticles (AuNPs) have promising medical and technological applications, however, little is known about their environmental fate and toxicity when contacting with biological systems, especially with plants. This study investigated the effects of AuNPs with two different coatings (citrate and polyvinylpyrrolidone [PVP]) as well as uncoated AuNPs on several important physiological and biochemical processes of lettuce. Monitored parameters included plant biomass, chlorophyll index, transpiration, nanoparticle size and zeta potential of the solutions, root leakage percentage, total protein content, as well as level of superoxide dismutases (SOD), hydrogen peroxide (H2O2), catalase (CAT), and guaiacol peroxidase (GPX). The results showed that AuNPs stabilized with different coating materials demonstrated different physiological and biochemical effects on lettuce. PVP coated AuNPs exhibited the strongest effect on plant physiology and biochemistry, while the other types of AuNPs showed limited effect compared with controls. These results suggest that the properties of coating materials play a key role in the toxic effect of AuNPs