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Effect of diameter of nanoparticles and capture cross-section library on macroscopic dose enhancement in boron neutron capture therapy.

Farhood B, Ghorbani M - J Contemp Brachytherapy (2014)

Bottom Line: Additionally, the effect of ENDF, JEFF, JENDL, and CENDL neutron capture cross-section libraries on MDEF was evaluated.Furthermore, the boron capture related dose component reduced in some extent with increase of diameter of (10)B nanoparticles.Based on the results of this study, it can be concluded that from physical point of view, various nanoparticle diameters have no dominant effect on average MDEF value in tumor.

View Article: PubMed Central - PubMed

Affiliation: Medical Physics Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

ABSTRACT

Purpose: The aim of this study is evaluation of the effect of diameter of (10)B nanoparticles and various neutron capture cross-section libraries on macroscopic dose enhancement in boron neutron capture therapy (BNCT).

Material and methods: MCNPX Monte Carlo code was used for simulation of a (252)Cf source, a soft tissue phantom and a tumor containing (10)B nanoparticles. Using (252)Cf as a neutron source, macroscopic dose enhancement factor (MDEF) and total dose rate in tumor in the presence of 100, 200, and 500 ppm of (10)B nanoparticles with 25 nm, 50 nm, and 100 nm diameters were calculated. Additionally, the effect of ENDF, JEFF, JENDL, and CENDL neutron capture cross-section libraries on MDEF was evaluated.

Results: There is not a linear relationship between the average MDEF value and nanoparticles' diameter but the average MDEF grows with increased concentration of (10)B nanoparticles. There is an increasing trend for average MDEF with the tumor distance. The average MDEF values were obtained the same for various neutron capture cross-section libraries. The maximum and minimum doses that effect on the total dose in tumor were neutron and secondary photon doses, respectively. Furthermore, the boron capture related dose component reduced in some extent with increase of diameter of (10)B nanoparticles.

Conclusions: Based on the results of this study, it can be concluded that from physical point of view, various nanoparticle diameters have no dominant effect on average MDEF value in tumor. Furthermore, it is concluded that various neutron capture cross-section libraries are resulted to the same macroscopic dose enhancements. However, it is predicted that taking into account the biological effects for various nanoparticle diameters will result in different dose enhancements.

No MeSH data available.


Related in: MedlinePlus

Geometry of applicator tube 252Cf source used in this study
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Figure 0001: Geometry of applicator tube 252Cf source used in this study

Mentions: A 252Cf (Applicator Tube [AT] model) source has been used as the source of neutrons [22, 25]. AT 252Cf source model is composed of a primary capsule, a secondary capsule, and an active core. The cylindrical active element is made of Pd:Cf2O3 ceramic metal with 15.0 mm length and 1.23 mm diameter having mass density of 12.0 g/cm3. The primary capsule is composed of a Pt/Ir-10% alloy (with mass density of 21.51 g/cm3) with inner diameter of 1.35 mm and outer diameter of 1.75 mm. The inner and outer lengths of the primary capsule are 15.50 and 17.78 mm, respectively. The secondary capsule has the same composition but its inner diameter is 1.80 mm and its outer diameter is 2.80 mm, while its inner and outer lengths are 17.82 mm and 23.14 mm, respectively. The inner and outer capsules have rounded with weld ends. There is a Bodkin eyelet with 0.635 mm diameter in the outer capsule [22]. Figure 1 illustrates the geometry of this source model.


Effect of diameter of nanoparticles and capture cross-section library on macroscopic dose enhancement in boron neutron capture therapy.

Farhood B, Ghorbani M - J Contemp Brachytherapy (2014)

Geometry of applicator tube 252Cf source used in this study
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4300365&req=5

Figure 0001: Geometry of applicator tube 252Cf source used in this study
Mentions: A 252Cf (Applicator Tube [AT] model) source has been used as the source of neutrons [22, 25]. AT 252Cf source model is composed of a primary capsule, a secondary capsule, and an active core. The cylindrical active element is made of Pd:Cf2O3 ceramic metal with 15.0 mm length and 1.23 mm diameter having mass density of 12.0 g/cm3. The primary capsule is composed of a Pt/Ir-10% alloy (with mass density of 21.51 g/cm3) with inner diameter of 1.35 mm and outer diameter of 1.75 mm. The inner and outer lengths of the primary capsule are 15.50 and 17.78 mm, respectively. The secondary capsule has the same composition but its inner diameter is 1.80 mm and its outer diameter is 2.80 mm, while its inner and outer lengths are 17.82 mm and 23.14 mm, respectively. The inner and outer capsules have rounded with weld ends. There is a Bodkin eyelet with 0.635 mm diameter in the outer capsule [22]. Figure 1 illustrates the geometry of this source model.

Bottom Line: Additionally, the effect of ENDF, JEFF, JENDL, and CENDL neutron capture cross-section libraries on MDEF was evaluated.Furthermore, the boron capture related dose component reduced in some extent with increase of diameter of (10)B nanoparticles.Based on the results of this study, it can be concluded that from physical point of view, various nanoparticle diameters have no dominant effect on average MDEF value in tumor.

View Article: PubMed Central - PubMed

Affiliation: Medical Physics Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

ABSTRACT

Purpose: The aim of this study is evaluation of the effect of diameter of (10)B nanoparticles and various neutron capture cross-section libraries on macroscopic dose enhancement in boron neutron capture therapy (BNCT).

Material and methods: MCNPX Monte Carlo code was used for simulation of a (252)Cf source, a soft tissue phantom and a tumor containing (10)B nanoparticles. Using (252)Cf as a neutron source, macroscopic dose enhancement factor (MDEF) and total dose rate in tumor in the presence of 100, 200, and 500 ppm of (10)B nanoparticles with 25 nm, 50 nm, and 100 nm diameters were calculated. Additionally, the effect of ENDF, JEFF, JENDL, and CENDL neutron capture cross-section libraries on MDEF was evaluated.

Results: There is not a linear relationship between the average MDEF value and nanoparticles' diameter but the average MDEF grows with increased concentration of (10)B nanoparticles. There is an increasing trend for average MDEF with the tumor distance. The average MDEF values were obtained the same for various neutron capture cross-section libraries. The maximum and minimum doses that effect on the total dose in tumor were neutron and secondary photon doses, respectively. Furthermore, the boron capture related dose component reduced in some extent with increase of diameter of (10)B nanoparticles.

Conclusions: Based on the results of this study, it can be concluded that from physical point of view, various nanoparticle diameters have no dominant effect on average MDEF value in tumor. Furthermore, it is concluded that various neutron capture cross-section libraries are resulted to the same macroscopic dose enhancements. However, it is predicted that taking into account the biological effects for various nanoparticle diameters will result in different dose enhancements.

No MeSH data available.


Related in: MedlinePlus