Aggregation Kinetics of Citrate and Polyvinylpyrrolidone Coated Silver Na in Monovalent and Divalent Electrolyte Solutions

The aggregation kinetics of silver nanoparticles (AgNPs) that were coated with two commonly use agents—citrate and polyvinylpyrrolidone (PVP)—were investigated. Time-resolved dynamic light (DLS) was employed to measure the aggregation kinetics of the AgNPs over a range of monovalen electrolyte concentrations. The aggregation behavior of citrate-coated AgNPs in NaCl was in excel with the predictions based on Derjaguin–Landau–Verwey–Overbeek (DLVO) theory, and the Ham of citrate-coated AgNPs in aqueous solutions was derived to be 3.7 × 10 J. Divalent electrolytes efficient in destabilizing the citrate-coated AgNPs, as indicated by the considerably lower critical c concentrations (2.1 mM CaCl and 2.7 mM MgCl vs. 47.6 mM NaCl). The PVP-coated AgNPs w significantly more stable than citrate-coated AgNPs in both NaCl and CaCl , which is likely due to repulsion imparted by the large, non-charged polymers. The addition of humic acid resulted in the the macromolecules on both citrateand PVP-coated AgNPs. The adsorption of humic acid induce electrosteric repulsion that elevated the stability of both nanoparticles in suspensions containing Na concentrations of CaCl . Conversely, enhanced aggregation occurred for both nanoparticles at high concentrations due to interparticle bridging by humic acid clusters. Introduction Because of the optical and antimicrobial properties and electrical conductivity of silver nanoparticl 4), these nanomaterials are already finding applications in a wide variety of fields, which includes b chemical, and electrical engineering. The combination of their antimicrobial activity and relative lo likely the key reason for nanosilver-containing products to presently comprise more than 50% of th consumer products that contain engineered nanoparticles (5). For example, AgNPs are being incorp Performing your original search, brookhaven 200sm and starch, in PMC will retrieve 2 records.