Heteroaggregation Of Citrate-Coated Silver Nanoparticles With Polystyrene And Silica Particles

Silver nanoparticles (AgNPs) have many different useful properties and are incorporated into many industrial products. However, once these particles enter the environment after use, they pose a threat to the safety of many organisms. Overall though, not much is known about these particles and how they interact with their environment. There is especially a lack of research as to how these particles aggregate with different particles. Investigating the stability of AgNPs in the presence of other colloids will give a better understanding of the mobility and toxicity of the particles in the environment. The zeta potentials of isolated AgNPs, AgNPs in the presence of polystyrene, and AgNPs in the presence of silica were taken via electrophoretic light scattering and compared with both kinetics and spectra data from UV-Vis spectroscopy. Both the zeta potentials and the data taken from UV-Vis spectroscopy indicated that the AgNPs were the most stable in the presence of polystyrene particles, less stable isolated, and least stable in the presence of silica particles. The average critical coagulation concentration (CCC) of the AgNPs in the presence of the polystyrene particles, isolated AgNPs, and AgNPs in the presence of the silica particles were 170.9±4.7, 149.7±2.0, and 81.9±9.3 mM NaNO3, respectively. Further research using transmission electron microscopy will determine the exact interactions between these particles