Validation of Dynamic Light Scattering and Differential Centrifugal Sedimentation Methods for Nanoparticle Characterisation

Abstract

A variety of techniques exists to analyse the size distribution of nanoparticles in a suspension. However, neither full method validation reports nor suitable reference materials with properly assigned values traceable to SI are easily found in literature or on the market, respectively. This paper presents results of in-house validation studies of Dynamic Light Scattering 9DLS) and Differential Centrifugal Sedimentation (DCS) methods. Repeatability and intermediate precision were assessed using the IRMM-304 reference material (silica nanoparticles suspended in an aqueous solution) to estimate the uncertainty contribution from within-day or day-to-day variation effects. Combined and expanded uncertainties were calculated with the goal to obtain a reliable measurement uncertainly valid for measuring silica nanoparticles or for particles with similar density and size range. The validated method will be used in the certification of nanoparticle reference materials.JRC.DG.D.2-Reference material