Application of Single-Particle ICP-MS to Determine the Mass Distribution and Number Concentrations of Environmental Nanoparticles and Colloids

Abstract

Analyzing the elemental compositions and size distributions of nanoparticles, colloids, and their aggregates in environmental samples represents a key task in understanding contaminant, substrate, and nutrient cycling. Single-particle ICP-MS (spICP-MS) is a high-throughput method that is capable of providing the elemental mass of thousands of particles within minutes. The challenge, however, lies in data analysis and interpretation, especially for complex environmental samples. Here we present successful applications of spICP-MS for environmental samples. We first analyzed the homoaggregation behavior of synthetic microplastic and magnetite (abiogenic and biogenic) nanoparticles. The measured distribution of aggregate mass was described as a function of the number of primary particles/aggregate (N pp). In tandem with dynamic light scattering data, differences in aggregates’ compactness (primary particles per nanometer) between samples can be determined. Second, we showed how sequential elemental analysis allows evaluation of the mobility of a toxic arsenic metalloid and its inferred association with colloidal Fe­(III) (oxyhydr)­oxides. Finally, we investigated the composition of heterogeneous iron–carbon-rich colloidal flocs, highlighting distinct colloidal Fe and C distributions and C/Fe ratios between samples from different permafrost thawing stages. On the basis of our results, we provide guidelines for successful sample preparation and promising future spICP-MS opportunities and applications with environmental samples.

Significance of Non-DLVO Interactions on the Co-Transport of Functionalized Multiwalled Carbon Nanotubes and Soil Nanoparticles in Porous Media

“…Single-particle ICP-MS also helps to identify and quantify the low concentrations and size of ENPs in the environment 45−47 and possibly ENPs-SNPs aggregates in the future. 88 The interfacial forces between colloids and collectors could be directly determined by AFM. 89 Both MD simulation and DFT could provide the interaction mechanism between molecules or/and atoms.…”

“…In fact, homo- and heteroaggregates in suspension can be distinguished by AF4-UV-DLS-ICP-MS by determining changes in size fraction and element composition. Single-particle ICP-MS also helps to identify and quantify the low concentrations and size of ENPs in the environment − and possibly ENPs-SNPs aggregates in the future . The interfacial forces between colloids and collectors could be directly determined by AFM .…”

Simultaneous Insight into Dissolution and Aggregation of Metal Sulfide Nanoparticles through Single-Particle Inductively Coupled Plasma Mass Spectrometry

“…Single-particle inductively coupled plasma mass spectrometry (spICP–MS) is an established nanoanalysis technique uniquely suited to fill the technical gap between sequential filtration and TEM. spICP–MS relies on the detection of pulses generated by single particles entering the plasma in a time-resolved mode. , To avoid coincidence (i.e., two particles entering the plasma at the same time), the technique is optimized for quantifying particle concentrations of ∼10 6 particles/mL or lower, a number considerably more representative of environmental concentrations. spICP–MS also allows for simultaneous quantification of the particle and dissolved phases.…”

Quantification of photooxidative defects in weathered microplastics using13C multiCP NMR spectroscopy

“…[17][18][19] Weathering gradually changes MP polymer chains to highly polar, heavily branched, mediumsized oligomers. 17 Polar and charged groups expressed on particle surfaces favour particle cell interactions and cellular responses, 20 as well as the formation of an ecocorona by adsorption of natural inorganic and organic colloidal particles 21,22 or by deposition of biolms due to microbe activity. 23,24 This in turn enhances the uptake by microorganisms.…”