Dosimetric consequences of gold nanoparticle clustering during photon irradiation

Kirkby, Charles; Koger, Brandon; Suchowerska, Natalka; McKenzie, David R.

doi:10.1002/mp.12620

Cited by 19 publications

(15 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similarly, a previous study 20 also found that when a cluster (with separation distance, SD 1 nm) of gold nanoparticles (GNPs, with r = 50 nm) randomly distributed in a water phantom is irradiated with a keV external photon beam, the secondary electrons produced from neighboring GNPs contribute to local dose in the periphery of a GNP and thus enhance dose. On the other hand, another study 38 found that for closely packed GNPs (with r = 25 nm) in a three-dimensional hexagonal arrangement, the clustering mitigates dose enhancement due to the self- absorption by the GNPs for both keV and MeV external photon beam irradiation. These results suggest in both RNT and external beam radiotherapy, the clustering effect on dose enhancement depends on the size and density of the nanoparticles as well as the cluster geometry.…”

Section: Resultsmentioning

confidence: 99%

Radio-enhancement effects by radiolabeled nanoparticles

Gholami

Maschmeyer

Kuncic

2019

Sci Rep

View full text Add to dashboard Cite

In cancer radiation therapy, dose enhancement by nanoparticles has to date been investigated only for external beam radiotherapy (EBRT). Here, we report on an in silico study of nanoparticle-enhanced radiation damage in the context of internal radionuclide therapy. We demonstrate the proof-of-principle that clinically relevant radiotherapeutic isotopes (i.e. 213Bi, 223Ra, 90Y, 177Lu, 67Cu, 64Cu and 89Zr) labeled to clinically relevant superparamagnetic iron oxide nanoparticles results in enhanced radiation damage effects localized to sub-micron scales. We find that radiation dose can be enhanced by up to 20%, vastly outperforming nanoparticle dose enhancement in conventional EBRT. Our results demonstrate that in addition to the favorable spectral characteristics of the isotopes and their proximity to the nanoparticles, clustering of the nanoparticles results in a nonlinear collective effect that amplifies nanoscale radiation damage effects by electron-mediated inter-nanoparticle interactions. In this way, optimal radio-enhancement is achieved when the inter-nanoparticle distance is less than the mean range of the secondary electrons. For the radioisotopes studied here, this corresponds to inter-nanoparticle distances <50 nm, with the strongest effects within 20 nm. The results of this study suggest that radiolabeled nanoparticles offer a novel and potentially highly effective platform for developing next-generation theranostic strategies for cancer medicine.

show abstract

Section: Resultsmentioning

confidence: 99%

Radio-enhancement effects by radiolabeled nanoparticles

Gholami

Maschmeyer

Kuncic

2019

Sci Rep

View full text Add to dashboard Cite

show abstract

“…We carried out both macroscopic and microscopic Monte Carlo simulations to reveal how GNP cluster formation affects the energy deposition to the GNPs and surrounding medium. Several groups previously investigated the effect on dose enhancement of clustered GNPs to the water medium, using models in which GNPs are densely packed and in direct contact with each other [28,29]. Our study modeled GNP clusters by using the parameters given by Peckys and De Jonge (who suggested that GNPs are packed inside vesicles) [24].…”

Section: Discussionmentioning

confidence: 99%

“…Recently, Zygmanski et al simulated the dose enhancement in simple planar array and slab cluster models and showed saturation of dose enhancement as the number of GNPs in the cluster increased [27]. Planar or hexagonally packed GNP clusters were previously investigated by other groups [28,29]. On the other hand, quantitative image analysis suggested that GNPs in clusters can actually become trapped inside vesicles [24].…”

mentioning

confidence: 99%

Investigation of energy absorption by clustered gold nanoparticles

Kwon

Sutherland

Makarova

et al. 2018

Nuclear Instruments and Methods in Physics Research Section B:

View full text Add to dashboard Cite

The utilization of gold nanoparticles (GNPs) as a radiation sensitizer has received broad attention. Although GNPs form clusters in living cells, most previous simulation studies have assumed a homogeneous distribution of GNPs. In this study, a GNP cluster was constructed for simulations and the impact of cluster formation on dose enhancement was examined. Energy absorption by the GNPs was compared between clustered and homogeneous distributions for several different GNP concentrations and diameters under 100 keV X-ray irradiations. Our simulations showed that clusters more efficiently absorbed the secondary electrons and photons produced by GNPs themselves. Furthermore, the impact of cluster formation on dose enhancement was more significant for smaller GNPs and higher concentrations. Our results suggest that previous simulations assuming a homogeneous GNP distribution have overestimated the dose enhancement, especially for smaller GNPs and higher concentrations. These findings should guide the selection of GNP size and concentration for effectively optimizing dose enhancement in future studies.

show abstract

“…22 On the other hand, when the NPs aggregate, the secondary electrons from the inner NP are more likely to be reabsorbed, rendering the outermost NPs to contribute to the dose enhancement. 23 In the Fig. 7, one can notice that the enhancement is localized at the very close vicinity of the discs, with a dose enhancement of approximately 5-fold observed within 0.5 mm around the microdisc, when the microdisc is perpendicular to the beam direction.…”

Section: Simulationsmentioning

confidence: 87%