Silver nanoparticles (AgNPs) exhibit many unique properties which are increasingly leading to their application in many areas of technology including microelectronics, pharmaceuticals, food packaging and other consumer products. As a result, there is currently a substantial regulatory activity [1] which is driving the need to identify suitable, robust techniques to detect and quantify AgNPs dispersed in environmental and/or complex matrices. Unfortunately, to accurately measure the nanoparticle size distribution of polydispersed samples is a complex and very difficult task [2]. In this work, different analytical techniques, Sedimentation Flow Field Fractionation (SdFFF), Asymmetrical Flow Field Flow Fractionation (AF4), Centrifugal Liquid Sedimentation (CLS) and Dynamic Light Scattering (DLS) have been used to give complementary size information about suspensions of silver nanoparticles (AgNPs) in the size range of 20-100 nm by taking advantage of the different physical principles on which are based. Particle morphology was controlled by TEM (Transmission Electron Microscopy). Quantitative mass and number particle size distributions were also calculated starting from UV-Vis signals and ICP-MS data and the results evaluated as a means to address the issue of determining nanoparticle size distributions as required for implementation of European regulations relating to labelling of nanomaterials in consumer products. The results will be discussed in light of possible particle aggregation state, analysis repeatability, size resolution and quantitative recoveries.
Critical experimental evaluation of key methods to detect, size, and quantify nanoparticolate silver
CONTADO, Catia
2015
Abstract
Silver nanoparticles (AgNPs) exhibit many unique properties which are increasingly leading to their application in many areas of technology including microelectronics, pharmaceuticals, food packaging and other consumer products. As a result, there is currently a substantial regulatory activity [1] which is driving the need to identify suitable, robust techniques to detect and quantify AgNPs dispersed in environmental and/or complex matrices. Unfortunately, to accurately measure the nanoparticle size distribution of polydispersed samples is a complex and very difficult task [2]. In this work, different analytical techniques, Sedimentation Flow Field Fractionation (SdFFF), Asymmetrical Flow Field Flow Fractionation (AF4), Centrifugal Liquid Sedimentation (CLS) and Dynamic Light Scattering (DLS) have been used to give complementary size information about suspensions of silver nanoparticles (AgNPs) in the size range of 20-100 nm by taking advantage of the different physical principles on which are based. Particle morphology was controlled by TEM (Transmission Electron Microscopy). Quantitative mass and number particle size distributions were also calculated starting from UV-Vis signals and ICP-MS data and the results evaluated as a means to address the issue of determining nanoparticle size distributions as required for implementation of European regulations relating to labelling of nanomaterials in consumer products. The results will be discussed in light of possible particle aggregation state, analysis repeatability, size resolution and quantitative recoveries.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
