engleski

The effect of glucose on toxicity of silver nanoparticles and ions in chlorella vulgaris

Silver nanoparticles (AgNPs) belong to a group of frequently used materials in medicine and science and are well known for their antimicrobial properties in many commercially available products, but due to their toxicity and reactivity, they can pose a risk to the aquatic environment. Since Chlorella vulgaris is one of the most ubiquitous microalgae inhabiting aquatic ecosystems, it is widely used as a model organism for assessing the impact of materials of anthropogenic origin, e.g. AgNPs, on aquatic habitats. Glucose is a source of energy for algae and improves their growth and viability. However, it can also act as a mild reducing agent and improve the stability of AgNPs and prevent their aggregation, so it is sometimes used as a surface coating for NPs. To evaluate the impact of AgNP- PVP on C. vulgaris, algae cultures were grown in a liquid BBM nutrient medium with and without the addition of 1% glucose. Once the algae reached the exponential growth phase, they were treated with 1.5 mg/L of either AgNP-PVP or ionic silver (AgNO3). To evaluate the effects of AgNP-PVP and AgNO3, changes in the algae growth, cell viability and rate of photosynthesis were analysed after 5 and 24 hours of exposure. Furthermore, to visualize ultrastructural changes after the treatments, algae cells were examined by transmission electron microscopy. To further examine the interaction between AgNPs and algal cells, a drop of treated algal cells, previously washed with ultrapure water, was added on a copper grid, air-dried, and then observed directly by TEM.

silver nanoparticles ; Chlorella vulgaris ; ultrastructure ; glucose

nije evidentirano