Critical Experimental Evaluation of Key Methods to Detect, Size and Quantify Nanoparticulate Silver

Different analytical techniques, Sedimentation Flow Field Fractionation (SdFFF), Asymmetrical Flow Field Flow Fractionation (AF4) and 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). Both SdFFF and AF4 were able to accurately size all AgNPs; among sedimentation based techniques, CLS underestimated the average sizes of larger samples (70 and 100 nm), but it produced the best separation of bimodal mixtures Ag40/60 and Ag40/70 mix compared to SdFFF. On the contrary, DLS overestimated the average sizes of the smallest samples (20 and 30 nm) and it was unable to deal with bimodal mix. Quantitative mass and number particle size distributions were also calculated starting from UV-Vis signals and ICP-MS data, to meet the very urgent task in the context of the European regulations for the labelling of nanomaterials in consumer products. The results were discussed in light of possible particle aggregation state, analysis repeatability, size resolution and quantitative recoveries.

CASCIO Claudia;  GILLILAND Douglas;  ROSSI Francois;  CALZOLAI Luigi;  CONTADO Catia; 

2015-01-19

AMER CHEMICAL SOC

JRC91328

0003-2700,   

http://pubs.acs.org/doi/abs/10.1021/ac503307r,    https://publications.jrc.ec.europa.eu/repository/handle/JRC91328,   

10.1021/ac503307r,