- •The observed sensitization of GNPs in MV beams is higher than the simulated DER.
- •The experimentally reported sensitization of GNPs in kV beams is less than the simulated DER.
- •There is an enhancement in Linear Energy Transfer (LET).
- •LET enhancement ratio shows an excellent agreement with the sensitization reported.
- •LETER is a potentially efficacious metric in predicting the biological outcome of GNP.
The metric dose enhancement ratio (DER) has been widely used to assess the enhancing capability of gold nanoparticles (GNPs). However, there is a large disparity between the observed radiobiological outcome and DER values. A new metric, linear energy transfer enhancement ratio (LETER), is introduced to bridge the gap between theoretical predictions and the experimentally measured sensitization.
The radiation transport code SCEPTRE is used to examine the efficacy of the proposed new metric. Different clusters of GNPs irradiated with x-ray photons generated at 120 kVp and therapeutic 6 MV photon beams are investigated. For each pattern, two GNPs sizes are examined 50 and 100 nm.
An enhancement in the linear energy transfer has been observed for both energies. In the case of 120 kVp, LETER is substantially lower than DER; moreover, it decreases with increasing GNP size. On the other hand, the results of 6 MV show that LETER is relatively higher than DER, and it increases with the size of GNP. For the studied energies, LETER is in good agreement with the sensitization reported in the literature.
The results indicate the merit of LETER as a better indicator of the radiobiological outcome of GNP aided radiotherapy.
To read this article in full you will need to make a payment
Purchase one-time access:Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
One-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:Subscribe to Physica Medica: European Journal of Medical Physics
Already a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
- A review on gold nanoparticles radiosensitization effect in radiation therapy of cancer.Rep Pract Oncol Radiother. 2010; 15: 176-180https://doi.org/10.1016/j.rpor.2010.09.001
- The dosimetric feasibility of gold nanoparticle-aided radiation therapy (GNRT) via brachytherapy using low-energy gamma-/x-ray sources.Phys Med Biol. 2009; 54: 4889-4905https://doi.org/10.1088/0031-9155/54/16/004
- The use of gold nanoparticles to enhance radiotherapy in mice.Phys Med Biol. 2004; 49: N309-N315https://doi.org/10.1088/0031-9155/49/18/N03
- Physical basis and biological mechanisms of gold nanoparticle radiosensitization.Nanoscale. 2012; 4: 4830-4838https://doi.org/10.1039/c2nr31227a
- Angular dose anisotropy around gold nanoparticles exposed to X-rays.Nanomedicine. 2017; 13: 1653-1661https://doi.org/10.1016/j.nano.2017.02.017
- Biological consequences of nanoscale energy deposition near irradiated heavy atom nanoparticles.Sci Rep. 2011; 1: 18https://doi.org/10.1038/srep00018
- Estimation of tumour dose enhancement due to gold nanoparticles during typical radiation treatments: a preliminary Monte Carlo study.Phys Med Biol. 2005; 50: N163https://doi.org/10.1088/0031-9155/50/15/N01
- Irradiation of gold nanoparticles by x-rays: Monte Carlo simulation of dose enhancements and the spatial properties of the secondary electrons production.Med Phys. 2011; 38: 624-631https://doi.org/10.1118/1.3539623
- Estimation of microscopic dose enhancement factor around gold nanoparticles by Monte Carlo calculations.Med Phys. 2010; 37: 3809-3816https://doi.org/10.1118/1.3455703
- Monte Carlo simulations of dose enhancement around gold nanoparticles used as X-ray imaging contrast agents and radiosensitizers.Medical Imaging 2014: Physics of Medical Imaging: International Society for Optics and Photonics. 2014 (p. 90331K)
- The dichotomous nature of dose enhancement by gold nanoparticle aggregates in radiotherapy.Nanomed (Lond). 2018; 13: 809-823https://doi.org/10.2217/nnm-2017-0344
- Cell-specific radiosensitization by gold nanoparticles at megavoltage radiation energies.Int J Radiat Oncol Biol Phys. 2011; 79: 531-539https://doi.org/10.1016/j.ijrobp.2010.08.044
- Radiosensitization by gold nanoparticles: effective at megavoltage energies and potential role of oxidative stress.Transl Cancer Res. 2013; 2: 269-279https://doi.org/10.3978/j.issn.2218-676X.2013.08.03
- CORRIGENDUM: biological consequences of nanoscale energy deposition near irradiated heavy atom nanoparticles.Sci Rep. 2013; 3: 1725https://doi.org/10.1038/srep00018
- Biomolecule induced nanoparticle aggregation: effect of particle size on interparticle coupling.J Colloid Interface Sci. 2007; 313: 724-734https://doi.org/10.1016/j.jcis.2007.04.069
- Linear energy transfer dependence of a normoxic polymer gel dosimeter investigated using proton beam absorbed dose measurements.Phys Med Biol. 2004; 49: 3847-3855https://doi.org/10.1088/0031-9155/49/17/002
- Analysis of the track-and dose-averaged LET and LET spectra in proton therapy using the geant4 Monte Carlo code.Med Phys. 2015; 42: 6234-6247https://doi.org/10.1118/1.4932217
- Microdosimetry of X-ray-irradiated gold nanoparticles.Radiat Prot Dosim. 2013; 155: 59-63https://doi.org/10.1093/rpd/ncs278
- Spatially limited effects of dose and let enhancement near tissue/gold interfaces at diagnostic X ray qualities.Radiat Prot Dosim. 2000; 90: 159-163https://doi.org/10.1093/oxfordjournals.rpd.a033109
- Radiation fields backscattered from material interfaces: I. Biological effectiveness.Radiat Res. 1998; 150: 406-415
- Radio-sensitization efficacy of gold nanoparticles in inhalational nanomedicine and the adverse effect of nano-detachment due to coating inactivation.Phys Med. 2019; https://doi.org/10.1016/j.ejmp.2019.02.013
- Sandia Computational Engine for Particle-Transport Cross Sections v. 0.0.Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)2017
- The Integrated TIGER Series of Coupled Electron/Photon Monte Carlo Transport Code Revision 4. ITS Version 6.2009 (SAND-2008-3331)
- Analytical linear energy transfer calculations for proton therapy.Med Phys. 2003; 30: 806-815https://doi.org/10.1118/1.1567852
- Physical parameter optimization scheme for radiobiological studies of charged particle therapy.Phys Med. 2018; 51: 13-21https://doi.org/10.1016/j.ejmp.2018.06.001
- Generalized concept of the LET-RBE relationship of radiation-induced chromosome aberration and cell death.J Radiat Res. 1999; 40: 59-69https://doi.org/10.1269/jrr.40.59
- Elevated LET components in clinical proton beams.Phys Med Biol. 2011; 56: 6677-6691https://doi.org/10.1088/0031-9155/56/20/011
- Relative biological effectiveness (RBE) values for proton beam therapy.Int J Radiat Oncol Biol Phys. 2002; 53: 407-421https://doi.org/10.1016/S0360-3016(02)02754-2
- Enhancing the effect of 4MeV electron beam using gold nanoparticles in breast cancer cells.Phys Med. 2017; 35: 18-24https://doi.org/10.1016/j.ejmp.2017.02.014
- Multifunctional chitosan-capped gold nanoparticles for enhanced cancer chemo-radiotherapy: an invitro study.Phys Med. 2018; 48: 76-83https://doi.org/10.1016/j.ejmp.2018.04.002
- Nanoparticles for radiation therapy enhancement: the key parameters.Theranostics. 2015; 5: 1030-1044https://doi.org/10.7150/thno.11642
- Gold nanoparticles as radiation sensitizers in cancer therapy.Radiat Res. 2010; 173: 719-728https://doi.org/10.1667/RR1984.1
Published online: March 23, 2019
Accepted: February 23, 2019
Received in revised form: January 16, 2019
Received: November 21, 2018
© 2019 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.