Numerical evaluation of the effectiveness of colloidal gold as a contrast agent
Abstract
Monte Carlo numerical simulations were conducted to evaluate the effectiveness of colloidal gold as a contrast agent. The simulations were conducted using a simple configuration, modeling a phantom to maintain the generality of the results, and the effects of the mass percentage of gold accumulated inside the tumor and the energy of the irradiating X-rays were evaluated, as well as other information, such as the energy spectrum of the photons reaching the detector and the change in the energy deposited inside the phantom. The contrast of the X-ray image due to the layer is calculated from the total energy of photons transmitted to the back surface of the phantom. The simulation revealed that colloidal gold with a mass percentage of 1.0% provided an image for which the contrast was almost 70% of that for bone of the same thickness when X-rays from conventional X-ray tubes were considered. Monochromatic X-rays of 44, 66, and 88 keV, which simulated the Compton scattering monochromatic X-ray source being developed, were also evaluated. X-rays at the first two energies did not have a significant advantage over the rays from the X-ray tubes. For colloidal gold with a mass percentage of 1.0%, the 88 keV monochromatic X-ray produced an image contrast that was about 10% higher than the contrast for bone of the same thickness, as suggested by the K-absorption energy of gold. However, the improvement was not large considering the difficulty involved in making such a high-energy monochromatic X-ray source available.
Keywords
Gold nanoparticles Monte Carlo simulation Radiotherapy Imaging agent Monochromatic X-rays Compton scatteringReferences
- 1.Mattrey RF, Aguirre DA. Advances in contrast media research. Acad Radiol. 2003;10:1450–60.CrossRefPubMedGoogle Scholar
- 2.Sharma P, Brown S, Walter G, Santra S, Moudgil B. Nanoparticles for bioimaging. Adv Colloid Interface Sci. 2006;123–126:471–85.CrossRefPubMedGoogle Scholar
- 3.Daniel MC, Astruc D. Gold nanoparticles: assembly, supramolecular chemistry, quantum-size-related properties, and applications toward biology, catalysis, and nanotechnology. Chem Rev. 2004;104:293–346.CrossRefPubMedGoogle Scholar
- 4.Dragun GN, Zelentsov EL, Zolotarev KV, Zorin YA, Krylova LF, Kulipanov GN, et al. Nontraditional contrast agents for mediastinal lymphography using synchrotron radiation. Nucl Instrum Methods Phys Res B. 1989;282:439–94.CrossRefGoogle Scholar
- 5.Dolbnya IP, Glazyrin AL, Dragun GN, Zelentsov EL, Zorin YA, Gorchakov VN, et al. Combined investigation of nontraditional X-ray contrast agents for indirect lymphography. Nucl Instrum Methods Phys Res A. 1995;359:357–60.CrossRefGoogle Scholar
- 6.Hainfeld JF, Slatkin DN, Smilowitz HM. The use of gold nanoparticles to enhance radiotherapy in mice. Phys Med Biol. 2004;49:N309–15.CrossRefPubMedGoogle Scholar
- 7.Paciotti GF, Myer L, Weinreich D, Goia D, Pavel N, McLaughlin RE, et al. Colloidal gold: a novel nanoparticle vector for tumor directed drug delivery. Drug Deliv. 2004;11:169–83.CrossRefPubMedGoogle Scholar
- 8.Paciotti GF, Kingston DGI, Tamarkin L. Colloidal gold: a novel nanoparticle platform for developing multifunctional tumor-targeted drug delivery vectors. Drug Dev Res. 2006;67:47–54.CrossRefGoogle Scholar
- 9.Visarial RK, Griffin RJ, Williams BW, Ebbini ES, Paciotti GF, Song CW, et al. Enhancement of tumor thermal therapy using gold nanoparticles-assisted tumor necrosis factor-α delivery. Mol Cancer Ther. 2006;5:1014–20.CrossRefGoogle Scholar
- 10.Herold DM, Das IJ, Stobbe CC, Iyer RV, Chapman JD. Gold microspheres: a selective technique for producing biologically effective dose enhancement. Int J Radiat Biol. 2000;76:1357–64.CrossRefPubMedGoogle Scholar
- 11.Jiang M, Mizuno K, Uesaka M, Sakamoto F, Yusa N, Nishiyama N, et al. X-ray DDS (drug delivery system) for dynamic imaging for cancer radiation therapy by using colloidal gold. Proc 7th Asia-Oceania Congr Medical Physics and 13th Natl Annual Meeting of Medical Physics, Huangshan, China, 23–27 Aug 2007, pp. 28–30.Google Scholar
- 12.Mori A, Kato T, Mizuno K, Yusa N, Okayasu R, Uesaka M. DNA damage induced by colloidal gold or its combined effect X-rays. Proc 10th Int Workshop on Radiation Damage to DNA, Fukushima, Japan, 8–12 June 2008 (in press).Google Scholar
- 13.Cho SH. Estimation of tumor dose enhancement due to gold nanoparticles during typical radiation treatment: a preliminary Monte Carlo study. Phys Med Biol. 2005;50:N163–73.CrossRefPubMedGoogle Scholar
- 14.Niidome T, Yamagata M, Okamoto Y, Akiyama Y, Takahashi H, Kawano T, et al. PEG-modified gold nanorods with a stealth character for in vivo applications. J Control Release. 2006;114:343–7.CrossRefPubMedGoogle Scholar
- 15.Hong K, Friend DS, Glabe CG, Papahadjopoulos D. Liposomes containing colloidal gold are a useful probe of liposome-cell interactions. Biochim Biophys Acta. 1983;732:320–3.CrossRefPubMedGoogle Scholar
- 16.Mizuno K, Jiang M, Uesaka M, Yusa N, Sakumi A, Muroya Y, et al. Materials for drug delivery system and its reaction with hydroxyl radicals. Abstr 2007 Fall Meeting of Atomic Energy Society Japan, Kitakyuushu, Japan, 27–29 Sep 2007, p. 356 (in Japanese).Google Scholar
- 17.Ulanski P, Zainuddin, Rosiak JM. Pulse radiolysis of poly(ethylene oxide) in aqueous solution I. Formation of macroradicals. Radiat Phys Chem. 1995;46:913–6.Google Scholar
- 18.Chitharani BD, Ghazani AA, Chan WCW. Determining the size and shape dependence of gold nanoparticle uptake into mammalian cells. Nano Lett. 2006;6:662–8.CrossRefGoogle Scholar
- 19.Jiang W, Kim BYS, Rutka JT, Chan WCW. Nanoparticle-mediated cellular response is size-dependent. Nat Nanotechnol. 2008;3:145–50.CrossRefPubMedGoogle Scholar
- 20.Hainfeld JF, Slatkin DN, Focella TM, Smilowitz HM. Gold nanoparticles: a new X-ray contrast agent. Br J Radiol. 2006;79:248–53.CrossRefPubMedGoogle Scholar
- 21.Cai QY, Kim SH, Choi KS, Kim SY, Byun SJ, Kim KW, et al. Colloidal gold nanoparticles as a blood-pool contrast agent for X-ray computed tomography in mice. Invest Radiol. 2007;12:797–806.CrossRefGoogle Scholar
- 22.Uesaka M, Sakamoto F, Dobashi K, Kaneyasu T, Yamamoto T, Meng D, et al. Monochromatic tunable Compton scattering X-ray source using X-band multi-bunch linac and YGA laser circulation system. Nucl Instrum Methods Phys Res B. 2007;261:867–70.CrossRefGoogle Scholar
- 23.International Commission on Radiation Units and Measurements. Photon, electron, proton and neutron interaction data for body tissues (ICRU report 46). Washington: ICRU Publications; 1992.Google Scholar
- 24.Hirayama H, Namito Y, Bielajew AF, Wilderman SJ, Nelson WR. The EGS5 code system (Report No: SLAC-R–730). Stanford: Stanford Linear Accelerator Center; 2007.Google Scholar