Use of molybdenite nanoparticles for photonuclear production of technetium-99m
The possibility production of ⁹⁹Mo radioisotope with using recoil nuclei of molybdenite nanoparticles from reaction ¹⁰⁰Mo(γ,n)⁹⁹Mo was investigated. The use of thermally stable molybdenite allows solving the problem of thermal loads of high-power electron beams. The enrichment of radioactive isotope...
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irk-123456789-1954792023-12-05T13:24:24Z Use of molybdenite nanoparticles for photonuclear production of technetium-99m Dikiy, N.P. Lyashko, Yu.V. Medvedeva, E.P. Medvedev, D.V. Uvarov, V.L. Fedorets, I.D. Application of nuclear methods The possibility production of ⁹⁹Mo radioisotope with using recoil nuclei of molybdenite nanoparticles from reaction ¹⁰⁰Mo(γ,n)⁹⁹Mo was investigated. The use of thermally stable molybdenite allows solving the problem of thermal loads of high-power electron beams. The enrichment of radioactive isotopes carried out by the effect of SzilardChalmers. Molybdenite nanoparticles were irradiated by bremsstrahlung with Emax=39 MeV. The recoil nuclei of ⁹⁹Mo separated by electrolysis at low concentration. The yield of ⁹⁹Mo from extractable phase amounted 3% for size nanoparticles 350 nm. Досліджено можливість отримання радіоізотопа ⁹⁹Mo з використанням ядер віддачі наночастинок молібденіту з реакції ¹⁰⁰Mo(γ,n)⁹⁹Mo. Використання термостійкого молібденіту дозволяє вирішити проблему теплових навантажень потужних електронних пучків. Збагачення радіоактивних ізотопів здійснювалося за допомогою ефекту Сциларда-Чалмерса. Наночастки молібденіту опромінювалися гальмівним випромінюванням з Emax=39 MeV. Ядра віддачі ⁹⁹Mo були відокремлені електролізом при низькій концентрації. Вихід ⁹⁹Mo з екстрагованої фази склав ~3% для наночастинок розміром 350 нм. Исследована возможность получения радиоизотопа ⁹⁹Mo с использованием ядер отдачи наночастиц молибденита из реакции ¹⁰⁰Mo(γ,n)⁹⁹Mo. Использование термостойкого молибденита позволяет решить проблему тепловых нагрузок мощных электронных пучков. Обогащение радиоактивных изотопов осуществлялось с помощью эффекта Сциларда-Чалмерса. Наночастицы молибденита облучались тормозным излучением с Emax=39 MeV. Ядра отдачи ⁹⁹Mo были отделены электролизом при низкой концентрации. Выход ⁹⁹Mo из экстрагируемой фазы составил ~3% для наночастиц размером 350 нм. 2019 Article Use of molybdenite nanoparticles for photonuclear production of technetium-99m / N.P. Dikiy, Yu.V. Lyashko, E.P. Medvedeva, D.V. Medvedev, V.L. Uvarov, I.D. Fedorets // Problems of atomic science and technology. — 2019. — № 6. — С. 149-152. — Бібліогр.: 16 назв. — англ. 1562-6016 PACS: 28.60; 81.07._b http://dspace.nbuv.gov.ua/handle/123456789/195479 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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Digital Library of Periodicals of National Academy of Sciences of Ukraine |
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DSpace DC |
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Application of nuclear methods Application of nuclear methods |
| spellingShingle |
Application of nuclear methods Application of nuclear methods Dikiy, N.P. Lyashko, Yu.V. Medvedeva, E.P. Medvedev, D.V. Uvarov, V.L. Fedorets, I.D. Use of molybdenite nanoparticles for photonuclear production of technetium-99m Вопросы атомной науки и техники |
| description |
The possibility production of ⁹⁹Mo radioisotope with using recoil nuclei of molybdenite nanoparticles from reaction ¹⁰⁰Mo(γ,n)⁹⁹Mo was investigated. The use of thermally stable molybdenite allows solving the problem of thermal loads of high-power electron beams. The enrichment of radioactive isotopes carried out by the effect of SzilardChalmers. Molybdenite nanoparticles were irradiated by bremsstrahlung with Emax=39 MeV. The recoil nuclei of ⁹⁹Mo separated by electrolysis at low concentration. The yield of ⁹⁹Mo from extractable phase amounted 3% for size nanoparticles 350 nm. |
| format |
Article |
| author |
Dikiy, N.P. Lyashko, Yu.V. Medvedeva, E.P. Medvedev, D.V. Uvarov, V.L. Fedorets, I.D. |
| author_facet |
Dikiy, N.P. Lyashko, Yu.V. Medvedeva, E.P. Medvedev, D.V. Uvarov, V.L. Fedorets, I.D. |
| author_sort |
Dikiy, N.P. |
| title |
Use of molybdenite nanoparticles for photonuclear production of technetium-99m |
| title_short |
Use of molybdenite nanoparticles for photonuclear production of technetium-99m |
| title_full |
Use of molybdenite nanoparticles for photonuclear production of technetium-99m |
| title_fullStr |
Use of molybdenite nanoparticles for photonuclear production of technetium-99m |
| title_full_unstemmed |
Use of molybdenite nanoparticles for photonuclear production of technetium-99m |
| title_sort |
use of molybdenite nanoparticles for photonuclear production of technetium-99m |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| publishDate |
2019 |
| topic_facet |
Application of nuclear methods |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/195479 |
| citation_txt |
Use of molybdenite nanoparticles for photonuclear production of technetium-99m / N.P. Dikiy, Yu.V. Lyashko, E.P. Medvedeva, D.V. Medvedev, V.L. Uvarov, I.D. Fedorets // Problems of atomic science and technology. — 2019. — № 6. — С. 149-152. — Бібліогр.: 16 назв. — англ. |
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Вопросы атомной науки и техники |
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| fulltext |
ISSN 1562-6016. ВАНТ. 2019. №6(124) 149
APPLICATION OF NUCLEAR METHODS
USE OF MOLYBDENITE NANOPARTICLES FOR PHOTONUCLEAR
PRODUCTION OF TECHNETIUM-99m
N.P. Dikiy1,2, Yu.V. Lyashko1,2, E.P. Medvedeva1,2,
D.V. Medvedev1, V.L. Uvarov1, I.D. Fedorets2
1National Science Center “Kharkov Institute of Physics and Technology”, Kharkiv, Ukraine;
2V.N. Karazin Kharkiv National University, Kharkiv, Ukraine
E-mail: ndikiy@kipt.kharkov.ua
The possibility production of 99Mo radioisotope with using recoil nuclei of molybdenite nanoparticles from reac-
tion 100Mo(γ,n)99Mo was investigated. The use of thermally stable molybdenite allows solving the problem of ther-
mal loads of high-power electron beams. The enrichment of radioactive isotopes carried out by the effect of Szilard-
Chalmers. Molybdenite nanoparticles were irradiated by bremsstrahlung with Emax=39 MeV. The recoil nuclei of
99Mo separated by electrolysis at low concentration. The yield of 99Mo from extractable phase amounted 3% for size
nanoparticles 350 nm.
PACS: 28.60; 81.07._b
INTRODUCTION
99mTc (T1/2=6 h) is being produced from the decay of
the 99Mo (T1/2=66 h). 99mTc produces a 140 keV gamma
ray and it is an ideal isotope for nuclear medicine imag-
ing [1]. 99Mo is using in the preparation of 99Mo-99mTc
generator. Usually 99Mo is being produced either by
neutron bombardment of MoO3 or as nuclear fission of
enriched uranium [1]. A significant difference between
of these two procedures is that 99Mo obtained from fis-
sion is “carrier free”. This allows to producing of 99Mo
with a specific activity of tens of thousands of Ci/g. The
method of photonuclear production of 99Mo character-
ized by considerable advantages [2 - 4]. The (γ,n)-
reaction does not be accompanied by a change in nuclear
charge. Therefore, the enrichment of radioactive isotopes
is been carried out using the effect of Szilard-Chalmers.
The high concentration of 99Mo is required for manufac-
turing of 99mTc-99Mo generators. These generators will
promote successful using 99mTc in nuclear medicine.
A feature of this study is the use of electrolysis to
separate of 99mTc. The electrolysis method allows the sepa-
ration of 99mTc from solutions with a lower specific con-
centration of 99Mo than, for example, when the extraction
of 99mTc using methyl ethyl ketone [2 - 4].
Currently molybdenum disulfide intensively investi-
gating d. This use molybdenum disulfide in optoelectric
device, to molecular and biomolecular sensors, for hy-
drodesulfurization catalyst, catalyst for hydrogen evolu-
tion reaction, catalyst for water splitting and chemical
reaction, various bioapplications [5, 6]. Another appli-
cation is photothermal therapy, which takes advantage
of its good dispersibility and superior absorbance of
near infrared. A molybdenum disulfide dispersion shows
7.8 times higher absorbance than graphene oxide, and its
extinction coefficients at 800 nm is 29.2 l·g-1·cm-1, which
is higher than gold nanorods. Visualisation of certain
organs or cells is one of the most important functions
for diagnosis and treatment. Based on the large atomic
number of Mo, MoS2 flakes as image contrast agent are
using for computed tomogram [5].
The purpose of the present investigation is the pro-
duction of a high specific activity 99Mo with using of
molybdenite nanoparticles and the effect of Szilard-
Chalmers.
RESULTS AND DISCUSSION
The energy of the recoil nucleus depends on the
pulse gamma ray, neutron pulse emitted, and the angle
between the directions of doing these pulses. The ener-
gy of the recoil nucleus Er expressed by the following
expression:
,
)(2)(
)(2
cos
)(2)(
)(2)(2
2/1
2
2
22
2
2
2
22
2
−++
+
−
−++
+
+
+
=
Mm
c
E
mMQE
mMc
MmE
c
E
mMQE
mM
m
cmM
ME
Er
γ
γ
γγ
γ
γ θ
where Er − recoil energy molybdenum atom; the M is
the mass of molybdenum atom; m − mass of the neu-
tron; the Q − energy nuclear reaction; c − the speed of
light; θ − the angle between the directions of the neu-
tron is-started-up and the incident photon
The estimate of medial energy of neutrons for gam-
ma radiation with the maximum energy of 39 MeV of
reaction 100Mo(γ,n)99Mo is equal to 450 keV (Fig. 1) [7].
Therefore, medial energy of recoil nuclei of 99Mo is
equal to 4.5 keV. Recoil nuclei 99Mo can leave nanopar-
ticles of MoS2 from the depth of 4.5 nm (Fig. 2).
Nuclear reaction 100Mo(γ,n)99Mo was used to obtain
99mTc. Samples of molybdenite nanoparticles were acti-
vated by bremsstrahlung from a linear electron accelera-
tor with E = 39 MeV and I = 4 µA within 2 hours. The
size of molybdenite nanoparticles approximately was
300…400 nm.
Isotope activity is measured by a Ge(Li)-detector
with the energy resolution of 3.2 at 1333 keV line
(Fig. 3). It is known that the diffusion coefficients of
molybdenum and technetium in molybdenite are differ-
ent [8]. This feature is using for separation of 99mTc.
ISSN 1562-6016. ВАНТ. 2019. №6(124) 150
Thus, chemical reagents with affinity to technetium [9]
are using.
Extraction problem of technetium. The parameters
of technetium electrolysis were the following: the cur-
rent is ~150 mA/cm2, electrolyte temperature − 30°C.
Electrolysis carried out in a quartz cell. The increase of
productivity of electrochemical deposition of the tech-
netium on the carbon cathode reached by means of the
use of a rotating electrode. The diffusion limiting cur-
rent id for a rotating electrode:
id = 0.62 F D2/3ω1/2υ-1/6 Co,
where ω − an angular speed of rotation of an electrode;
υ − kinematic viscosity; Co − concentration of a re-
quired component in volume and D − diffusion factor.
Therefore changing the speed of rotation of an elec-
trode, we can change the limiting current density.
Fig. 1. The energy distribution of photo nucleons
predicted by the statistical theory [3]
0 2 4 6 8 10
2
4
6
8
Ra
ng
e,
n
m
Energy molybdenum, keV
range molybdenum in MoS2
Fig. 2. 99Mo ranges in natural molybdenum disulfide
1000 2000 3000 4000 5000
101
102
103
1129 keV
90Nb
1191 keV 96Nb
460 keV
95Nb
569 keV
96Nb235 keV 95mNb
181 keV 99Mo
511 keV 778 keV,99Mo
co
un
ts
number channel
molybdenite140.5 keV 99mTc
739 keV,99Mo
Fig. 3. The spectrum of molybdenite nanoparticles
after irradiate by bremstrunglung with Emax=39 MeV
Wettability of molybdenite increases with the reduc-
tion of the size nanoparticles. Electrolysis oxidation
oxidizes the molybdenite surface slightly and oxygen
becomes attached to the surface of the molybdenite lay-
er (Fig. 4). With prolonged retention after electrolysis
oxidation, molybdenum oxide can dissolve as molyb-
denum oxide ions, such as MoO2
-4. As a result, the mo-
lybdenite surface becomes hydrophobic with prolonged
retention [10]. Molybdenite is hydrophobic. On the oth-
er hand for molybdenite, with electrolysis oxidation,
molybdenum oxide produced but surface keeps weak
hydrophobic since molybdenum oxide is soluble. With
retention in electrolyte after electrolysis, surface keeps
weak hydrophobic since a still small amount of molyb-
denum oxide stayed on the surface.
Fig. 4. Properties of molybdenum disulfide during
electrolysis
Fig. 5. Structure of molybdenum disulfide
The crystalline structure of molybdenite with hydro-
phobic face sand hydrophilic edges shown (Fig. 5).
The method of electrolysis works with a great low
specific concentration of 99mTc. The specific concentra-
tion of 99mTc is in 100 less for this case than at use of
extraction with the help of methyl-ethyl ketone (Fig. 6)
[11, 12].
1000 2000 3000
1
10
100
1000
co
un
ts
number channel
extract 99mTc
140.5 keV 99mTc
511 keV
Fig. 6. The spectrum of extract 99mTc
Protons with energy 30 MeV used for production of
99Мо from nanoparticles of MoS2 [13, 14].
Due to unexpected outages or planned and un-
planned reactor shutdown, significant 99mTc shortages
appeared as a problem since 2008.
ISSN 1562-6016. ВАНТ. 2019. №6(124) 151
We note the tendency for the production of the 99Mo
isotope at charged particle accelerators. The new meth-
ods have a number of advantages compared with the
production of 99Mo at the reactors. One can note the
almost absence of radioactive waste, as well as the more
economic characteristics of the production of the 99Mo
isotope [15].
However, there are problems of heat removal from
the target. For this reason, sapphire, a ceramic material
with one of the highest thermal conductivities
(60 Wm−1⋅K−1), and synthetic diamond (CVD), a mate-
rial with an extremely high thermal conductivity (up to
2000 Wm−1⋅K−1), are proposed as the components of the
target backing plate. In order to minimize the thermal
resistance related to the ceramic part (again, to optimize
the heat exchange of the target), its thickness was mini-
mized [16].
Note that US-based NorthStar Medical Radioiso-
topes and Belgium’s Ion Beam Applications (IBA) have
signed a contract under which IBA would supply up to
eight Rhodotron TT300 HE electron beam accelerators
to NorthStar, which has issued purchase orders for the
first two units. Six more will be delivered in coming
years. This accelerator have very high power and energy
resolution: 125 kW, 40 MeV, ~5% energy spread.
CONCLUSIONS
The possibility of photonuclear production of 99Mo
by using recoil nuclei of molybdenite nanoparticles
from reaction 100Mo(γ,n)99Mo has been found.
The use of thermally stable molybdenite allows solv-
ing the problem of thermal loads when using high-
power electron beams.
The electrolysis of molybdenite nanoparticles allows
separating technetium-99m at low concentration.
The use MoS2 nanoparticles with size 15 nm and of
bremsstrahlung with Emax=25 MeV on 10 kW electron
accelerator will allow producing 0.8 GBq/g per day of
99mTc with a high specific activity. It simplifies the use
of 99mTc in medical institutions.
This work supported by IAEA Research Contract
No: UKR-22435 “Production of Tc-99m on Electron
Accelerators”.
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13. A.A. Artyukhov, V.A. Zagryadskii, Y.M. Kravets, et
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Article received 14.10.2019
ISSN 1562-6016. ВАНТ. 2019. №6(124) 152
ИСПОЛЬЗОВАНИЕ НАНОЧАСТИЦ МОЛИБДЕНИТА ДЛЯ ФОТОЯДЕРНОГО ПРОИЗВОДСТВА
ТЕХНЕЦИЯ-99m
Н.П. Дикий, Ю.В. Ляшко, Е.П. Медведева, Д.В. Медведев, В.Л. Уваров, И.Д. Федорец
Исследована возможность получения радиоизотопа 99Mo с использованием ядер отдачи наночастиц мо-
либденита из реакции 100Mo(γ,n)99Mo. Использование термостойкого молибденита позволяет решить про-
блему тепловых нагрузок мощных электронных пучков. Обогащение радиоактивных изотопов осуществля-
лось с помощью эффекта Сциларда-Чалмерса. Наночастицы молибденита облучались тормозным излучени-
ем с Emax=39 МэВ. Ядра отдачи 99Mo были отделены электролизом при низкой концентрации. Выход 99Мо из
экстрагируемой фазы составил ~3% для наночастиц размером 350 нм.
ВИКОРИСТАННЯ НАНОЧАСТИНОК МОЛІБДЕНІТУ ДЛЯ ФОТОЯДЕРНОГО ВИРОБНИЦТВА
ТЕХНЕЦІЯ-99m
М.П. Дикий, Ю.В. Ляшко, О.П. Медведєва, Д.В. Медведєв, В.Л. Уваров, І.Д. Федорець
Досліджено можливість отримання радіоізотопа 99Mo з використанням ядер віддачі наночастинок моліб-
деніту з реакції 100Mo(γ,n)99Mo. Використання термостійкого молібденіту дозволяє вирішити проблему теп-
лових навантажень потужних електронних пучків. Збагачення радіоактивних ізотопів здійснювалося за до-
помогою ефекту Сциларда-Чалмерса. Наночастки молібденіту опромінювалися гальмівним випромінюван-
ням з Emax=39 МеВ. Ядра віддачі 99Mo були відокремлені електролізом при низькій концентрації. Вихід 99Mo
з екстрагованої фази склав ~3% для наночастинок розміром 350 нм.
INTRODUCTION
RESULTS AND DISCUSSION
references
ИСПОЛЬЗОВАНИЕ НАНОЧАСТИЦ МОЛИБДЕНИТА ДЛЯ ФОТОЯДЕРНОГО ПРОИЗВОДСТВА технеция-99m
ВИКОРИСТАННЯ НАНОЧАСТИНОК МОЛІБДЕНІТУ ДЛЯ ФОТОЯДЕРНОГО ВИРОБНИЦТВА технеція-99m
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