1 research outputs found
Hydrodynamic Chromatography Coupled with Single Particle-Inductively Coupled Plasma Mass Spectrometry for Investigating Nanoparticles Agglomerates
Studying
the environmental fate of engineered or natural colloids requires
efficient methods for measuring their size and quantifying them in
the environment. For example, an ideal method should maintain its
correctness, accuracy, reproducibility, and robustness when applied
to samples contained in complex matrixes and distinguish the target
particles from the natural colloidal background signals. Since it
is expected that a large portion of nanoparticles will form homo-
or heteroagglomerates when released into environmental media, it is
necessary to differentiate agglomerates from primary particles. At
present, most sizing techniques do not fulfill these requirements.
In this study, we used online coupling of two promising complementary
sizing techniques: hydrodynamic chromatography (HDC) and single-particle
ICPMS analysis to analyze gold nanoparticles agglomerated under controlled
conditions. We used the single-particle mode of the ICPMS detector
to detect single particles eluted from an HDC-column and determine
a mass and an effective diameter for each particle using a double
calibration approach. The average agglomerate relative density and
fractal dimension were calculated using these data and used to follow
the morphological evolution of agglomerates over time during the agglomeration
process. The results demonstrate the ability of HDC coupled to single-particle
analysis to identify and characterize nanoparticle homoagglomerates
and is a very promising technique for the analysis of colloids in
complex media