Quantifying Chemical Composition and Reaction Kinetics of Individual Colloidally Dispersed Nanoparticles

Abstract

To control a nanoparticle's chemical composition and thus function, researchers require readily accessible and economical characterization methods that provide quantitative in situ analysis of individual nanoparticles with high throughput.Here, we established dual analyte single-particle inductively coupled plasma quadrupole mass spectrometry to quantify the chemical composition and reaction kinetics of individual colloidal nanoparticles. We determined the individual bimetallic nanoparticle mass and chemical composition changes during two different chemical reactions: (i) nanoparticle etching and (ii) element deposition on nanoparticles at a rate of 300+ nanoparticles/min. Our results revealed the heterogeneity of chemical reactions at the single nanoparticle level. This proof-of-concept study serves as a framework to quantitatively understand the dynamic changes of physicochemical properties that individual nanoparticles undergo during chemical reactions using a commonly available mass spectrometer. Such methods will broadly empower and inform the synthesis and development of safer, more effective, and more efficient nanotechnologies that use nanoparticles with defined functions.

Nanoparticle Surface Engineering with Heparosan Polysaccharide Reduces Serum Protein Adsorption and Enhances Cellular Uptake

“…We did not observe significant differences in hydrodynamic diameter for AuNPs modified with >0.5 HEP/nm 2 before and after FBS incubation (Figure C and Figure S9). To demonstrate the broad applicability of this HEP surface modification strategy, we additionally synthesized HEP-coated AgNPs and liposomes. − We observed no significant changes in hydrodynamic diameter for HEP-coated AgNPs and liposomes before and after FBS incubation indicating minimal interactions between the nanoparticle surfaces and serum proteins (Figure S11). Our findings suggest that the HEP surface modification strategy effectively minimizes serum protein adsorption onto the surfaces of various nanoparticles, that is, AuNPs, AgNPs, and liposomes.…”

Living in a transient world: ICP-MS reinvented via time-resolved analysis for monitoring single events

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