Photochemical synthesis of silver nanoparticles and evaluation of their toxicity on cell suspension culture of Nicotiana tabacum

Silver nanoparticles (Ag NPs) are one of the extensively used nanomaterials in the industry because of their special physicochemical properties as well as antibacterial and anti-inflammatory activities. The Ag NPs released from these products could enter into the environments through numerous routes. Therefore, it is necessary to consider the potential environmental impact of Ag NPs, especially on plants. In this present study, Ag NPs were synthesized using photoreduction method and their potential toxicity on cell suspension cultures of Nicotiana tabacum was evaluated. The synthesized Ag NPs were characterized by using X-ray powder diffraction, scanning electron microscopy, and dynamic light scattering techniques. Cell viability was assessed using triphenyl-tetrazolium chloride (TTC) assay. Subsequently, the dry weight of the samples was measured as growth characteristic of cell cultures. The average particle size of Ag NPs was about 40 nm. A significant decline in viability observed when cells were treated with Ag NPs after 2 day, which was approximately 95, 19, 11, 2 and 3 % for 5, 10, 15, 20 and 25 mg L-1 of Ag NPs, respectively. In the case of the lowest and the highest concentrations (5 and 25 mg L-1), the final dry weight was 72 and 44 % compared to the control. Our results suggest that Ag NPs are highly toxic to N. tabacum cells

Keywords:

Nicotiana tabacum , Oxidative stress , Silver nanoparticles , Toxicity