Environmental Engineering Reference
In-Depth Information
13.4.1 Assessment of NTA
Vagner et al. [
18
] present a method for improving polydisperse particle size
distributions based on the logarithmic transform of the estimated diameters to
reduce the heteroscedasticity, which is partly due to the constant coefficient of
variation of the value of diameter. Calculated cluster proportions were validated
and verified by Monte-Carlo simulations of polydisperse suspensions, NTA mea-
surements, and SEM images.
In Nanoparticle Tracking Analysis for the Multiparameter Characterization and
Counting of Nanoparticle Suspensions Wright [
19
] describes application of NTA to
the analysis of 100 nm polystyrene nanospheres in liquid suspension. The technique
can be adapted for use with nearly all particulate materials with sizes between
10 nm and 1
μ
m.
13.4.2 Nanotoxicology
Montes-Burgos et al. [
20
] investigated the use of NTA (with Nanosight software) as
a tool for the characterization of particle size and coating properties preceding a
nanotoxicology test. Long videos (166 s) were used for measuring diluted samples
of standard Au nanoparticles with 60-nm nominal size and mixtures of gold with
human plasma in stable conditions (without aggregation). A correction for the
broadness of the size distribution of the particles was also presented.
In Nanoparticle reactivity toward dithiothreitol, Sauvain et al. [
21
] studied the
ability of particles to catalyze the transfer of electrons from dithiothreitol to oxygen,
in an approach to measure the oxidative potential of particles. The agglomeration-
size distribution was determined for carbon-based NPs (carbon black and diesel
standards), titanium-dioxide (two different types), and silica NPs using NTA.
The influence of proteins on the dispersibility and aggregation kinetics of
PVP-coated silver nanoparticles (AgNPs) and citrate-stabilized silver nanoparticles
was studied using a self-constructed device and software that monitored the indi-
vidual movement of single particles in biological medium [
22
]. The many individ-
ual samples were analyzed for determination of size and fitted into a distribution
histogram.
Patrick Hole et al. [
23
] in his study looks at the reproducibility using technique
Nanoparticle Tracking Analysis (NTA) on a range of particle sizes and materials in
several different media. In his study are presented analytical and experimental
facilities in nanotechnology, medicine and natural sciences with the goal of devel-
oping and implementing best practice and quality in all aspects of nanosafety
assessment.
