Rapid advancement of nanotechnology has caused serious concerns over the potential release and accumulation of engineered nanoparticles (ENPs) in the environment. Gold nanoparticles (AuNPs) in particular, has attracted significant attention due to their broad applications. However, most previous toxicity studies have been heavily focused on animal and human cell lines, with limited information available for the AuNPs plant interactions. This study aimed to elucidate the impact of surface charge on the phytotoxicity and plant uptake of AuNPs by Phaseolus vulgaris (bush bean), an important food crop. The results showed that 5 mg/L of AuNPs exerted inconsequential impact on the physiological processes of plants, regardless of the surface property. However, AuNPs displayed significant surface charge-dependent effects on important biochemical parameters such as the concentrations of hydrogen peroxide in plant roots and the activities of several enzymatic antioxidants. Deposition of AuNPs on plant root surface was observed for all types of AuNPs. However, surface charge affected the internalization of AuNPs in plant root cells and their subcellular localization. Overall, the study revealed that the physical and chemical properties AuNPs play important roles in their interactions with agricultural crops and consideration of the unique properties of nanoparticles is important in assessing their food safety concerns.
Citation: Ma X, Quah B. 2016. Effects of Surface Charge on the Fate and Phytotoxicity of Gold Nanoparticles to Phaseolus vulgaris. J Food Chem Nanotechnol 2(1): 57-65.