Zetasizer nano ns dts 1060

The morphology of the nanoparticles was analyzed by High Resolution Transmission Electron Microscopy (HR-TEM) using a JEM-2010 (JEOL^©). AgNP average diameter (Ø_Ag) and size distribution analysis was determined from TEM micrographs (n = 150) using ImageJ Software [36 (link)]. Zeta potential (ζ) and hydrodynamic diameter (Ø_hydro) were determined by dynamic light scattering (DLS) using a Zetasizer Nano Ns DTS 1060 (Malvern Instruments^®). Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) measurements were performed with a DSC/TGA thermal analysis system (SDT Q600, Newtown, PA, USA) under argon atmosphere from 30 to 750 °C at a rate of 10 °C min⁻¹. Moreover, AgNP dilutions were used to determine plasmon resonance by UV/Vis spectroscopy using a JENWAY 6705 spectrophotometer (Cole-Parmer^©).

The AgNPs formulation used in this work is a stable aqueous suspension that contains 1.2% weight of metallic silver stabilized with 18.8% weight of PVP, commercially available as Argovit™. The final concentration of the suspension is 200 mg/mL (20%) of AgNPs. The AgNPs of this formulation has been described as a spheroidal shape by transmission electron microscopy (TEM) with a diameter distribution between 1 to 90 nm and an average size of 35 ± 12 nm. The hydrodynamic diameter is 70 nm, with a zeta potential of −5 mV and a plasmon resonance found at 420 nm. All determinations performed in distilled water [45 (link)]. Silver nanoparticles were donated by Vasily Burmistrov of Vector-Vita Scientific and Production Center (Novosibirsk, Russia). The UV-vis, zeta potential, and hydrodynamic diameter for AgNPs batch used in this work were determined in distilled water. The UV-vis spectra were acquired with an Agilent Cary 60 spectrophotometer (Agilent Technologies, Santa Clara, CA, USA), and the absorption maximum was observed on 424 nm. The zeta potential (−14 mV) and the hydrodynamic diameter (95 nm) were determined with a Zetasizer Nano NS DTS-1060 (Malvern Panalytical Ltd., Worcestershire, UK) The values obtained agree with those reported by the producers.