10.6084/m9.figshare.9942845.v1
Callum P. Scotson
Callum P.
Scotson
Maria Munoz-Hernando
Maria
Munoz-Hernando
Simon J. Duncan
Simon J.
Duncan
Siul A. Ruiz
Siul A.
Ruiz
Samuel D. Keyes
Samuel D.
Keyes
Arjen van Veelen
Arjen
van Veelen
Iain E. Dunlop
Iain E.
Dunlop
Tiina Roose
Tiina
Roose
AU_in_f from Stabilizing gold nanoparticles for use in X-ray computed tomography imaging of soil systems
The Royal Society
2019
gold
nanoparticle
soil
x-ray
contrast
stability
2019-10-05 12:59:22
Dataset
https://rs.figshare.com/articles/dataset/AU_in_f_from_Stabilizing_gold_nanoparticles_for_use_in_X-ray_computed_tomography_imaging_of_soil_systems/9942845
This investigation establishes a system of gold nanoparticles that show good colloidal stability as an X-ray computed tomography (XCT) contrast agent under soil conditions. Gold nanoparticles offer numerous beneficial traits for experiments in biology including: comparatively minimal phytotoxicity, X-ray attenuation of the material and the capacity for functionalization. However, soil salinity, acidity and surface charges can induce aggregation and destabilize gold nanoparticles, hence in biomedical applications polymer coatings are commonly applied to gold nanoparticles to enhance stability in the <i>in vivo</i> environment. Here we first demonstrate non-coated nanoparticles aggregate in soil-water solutions. We then show coating with a polyethylene glycol (PEG) layer prevents this aggregation. To demonstrate this, PEG-coated nanoparticles were drawn through flow columns containing soil and were shown to be stable; this is in contrast with control experiments using silica and alumina-packed columns. We further determined that a suspension of coated gold nanoparticles which fully saturated soil maintained stability over at least 5 days. Finally, we used time resolved XCT imaging and image based models to approximate nanoparticle diffusion as similar to that of other typical plant nutrients diffusing in water. Together, these results establish the PEGylated gold nanoparticles as potential contrast agents for XCT imaging in soil.