Results of an interlaboratory method performance study for the size determination and quantification of silver nanoparticles in chicken meat by single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS)

Stefan Weigel,Ringo Grombe,Ruud Peters,Katrin Loeschner,Thomas P J Linsinger

doi:10.1007/s00216-017-0427-2

Abstract

Single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) promises fast and selective determination of nanoparticle size and number concentrations. While several studies on practical applications have been published, data on formal, especially interlaboratory validation of sp-ICP-MS, is sparse. An international interlaboratory study was organized to determine repeatability and reproducibility of the determination of the median particle size and particle number concentration of Ag nanoparticles (AgNPs) in chicken meat. Ten laboratories from the European Union, the USA, and Canada determined particle size and particle number concentration of two chicken meat homogenates spiked with polyvinylpyrrolidone (PVP)-stabilized AgNPs. For the determination of the median particle diameter, repeatability standard deviations of 2 and 5% were determined, and reproducibility standard deviations were 15 and 25%, respectively. The equivalent median diameter itself was approximately 60% larger than the diameter of the particles in the spiking solution. Determination of the particle number concentration was significantly less precise, with repeatability standard deviations of 7 and 18% and reproducibility standard deviations of 70 and 90%.

Highlights

Particles with dimensions in the nanoscale may show different properties from the same chemical material in its bulk form, either due to the increased surface-to-volume ratio or the emergence of quantum phenomena at these small ranges
The same laboratories that participated in the previous intercomparison for sp-ICP-MS of Ag nanoparticles in food simulants [20] were invited to participate in this study
All ten laboratories had participated in the first sp-ICP-MS interlaboratory study on Ag nanoparticles (AgNPs) in food simulants

Summary

Introduction

Particles with dimensions in the nanoscale (defined as 1– 100 nm by ISO/TS 80004-1 [1]) may show different properties from the same chemical material in its bulk form, either due to the increased surface-to-volume ratio or the emergence of quantum phenomena at these small ranges Such particles have a significant potential for improved material properties but may have adverse effects. To avoid a multitude of conflicting definitions of nanomaterial, the European Commission has published a recommendation for a definition [4] which it intends to use in future regulation This definition defines a nanomaterial as Bnatural, incidental or manufactured material containing particles, in an unbound state or as an aggregate or as an agglomerate and where, for 50 % or more of the particles in the number size distribution, one or more external dimensions is in the size range 1 nm-100 nm.^. Of the most commonly used techniques for the determination of the diameters of nanoparticles, only electron microscopy (EM), particle tracking analysis (PTA), and single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) deliver number-based particle size distributions

Methods

Results

Conclusion