How the surface properties affect the nanocytotoxicity of silver? Study of the influence of three types of nanosilver on two wheat varieties

The influence of silver nanoparticles on calli cells of stress tolerant—Parabola and stress sensitive—Raweta wheat genotypes (Triticum aestivum L.) was studied. Three types of silver nanoparticles (AgNPs) were tested: cystamine-stabilized (positively charged), unmodified, synthesized using sodium borohydride and citrate-stabilized AgNPs, both negatively charged. Physico-chemical properties of silver nanoparticles were investigated by: UV–Vis spectroscopy, dynamic light scattering used for electrophoretic mobility and hydrodynamic diameter determination and transmission electron microscopy. The evaluation of cytotoxicity was estimated basing on lipid peroxidation, proline content and antioxidant enzymes activity. For sensitive variety every type of nanoparticles induced stress (proline increase) in cells, but positively charged nanoparticles were most cytotoxic. Treatment of stress tolerant Parabola by AgNPs caused the increase in SOD activity, suggesting the occurrence of oxidative stress in cells, confirmed by the increase of membrane lipid peroxidation. Negatively charged AgNPs were significantly more cytotoxic to the calli cells of sensitive variety in comparison to tolerant one.