Method for express determination of medical radionuclides ⁹⁹ᵐTc, ⁶⁷Cu concentration using spectrometer based on Si planar detector
The method of express analysis provides the measurement of radiation spectra of medical radionuclides by a detection module based on an uncooled silicon planar detector and a "scintillator-silicon photosensor" type module. A spectrometric device for express analysis of radionuclide concent...
Збережено в:
| Дата: | 2017 |
|---|---|
| Автори: | , , , , , , |
| Формат: | Стаття |
| Мова: | English |
| Опубліковано: |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України
2017
|
| Назва видання: | Вопросы атомной науки и техники |
| Теми: | |
| Онлайн доступ: | http://dspace.nbuv.gov.ua/handle/123456789/136208 |
| Теги: |
Додати тег
Немає тегів, Будьте першим, хто поставить тег для цього запису!
|
| Назва журналу: | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| Цитувати: | Method for express determination of medical radionuclides ⁹⁹ᵐTc, ⁶⁷Cu concentration using spectrometer based on Si planar detector / O.S. Deiev, S.K. Kiprich, N.I. Maslov, V.D. Ovchinnik, M.Y. Shulika, G.P. Vasiliev, V.I. Yalovenko // Вопросы атомной науки и техники. — 2017. — № 6. — С. 117-121. — Бібліогр.: 14 назв. — англ. |
Репозитарії
Digital Library of Periodicals of National Academy of Sciences of Ukraine| id |
irk-123456789-136208 |
|---|---|
| record_format |
dspace |
| spelling |
irk-123456789-1362082018-06-17T03:04:52Z Method for express determination of medical radionuclides ⁹⁹ᵐTc, ⁶⁷Cu concentration using spectrometer based on Si planar detector Deiev, O.S. Kiprich, S.K. Maslov, N.I. Ovchinnik, V.D. Shulika, M.Y. Vasiliev, G.P. Yalovenko, V.I. Детекторы и детектирование ядерных излучений The method of express analysis provides the measurement of radiation spectra of medical radionuclides by a detection module based on an uncooled silicon planar detector and a "scintillator-silicon photosensor" type module. A spectrometric device for express analysis of radionuclide concentration has been developed and its prototyping has been carried out, confirming the operability of the device. The spectrometer analyzer is powered from the USB port of the PC (including a laptop) that provides the possibility of autonomous operation. Test measurements were carried out using the prototype of the spectrometer and X-ray sources, as well as spectral distributions of the radiation of real samples of ⁹⁹ᵐTc in a special container (glass ampoule). For a Si-PIN-detector with a thickness of 300 μm, the emission spectrum consists of a line of ⁹⁹ᵐTc with an energy of 140.5 keV and two peaks of the characteristic X-ray radiation (CXR) of technetium. The calculation in GEANT4 shows the matching of the ⁹⁹ᵐTc activities obtained from the registration of CXR and the main line. A measurement of the technetium concentration both by the 140.5 keV line and on the CXR radiation was proposed that significantly increases the speed of the data accumulation. Методика експрес-аналізу передбачає вимір спектрів випромінювання медичних радіонуклідів детектуючим модулем на основі неохолоджуваного кремнієвого планарного детектора і модулем типу «сцинтилятор - кремнієвий фотосенсор». Розроблено спектрометричний пристрій для експрес-аналізу концентрації радіонуклідів і проведено його макетування, що підтверджує працездатність пристрою. Живлення спектрометра-аналізатора виконано від USB-порту ПК (в тому числі, ноутбука), що забезпечує можливість автономної роботи. Проведено тестові вимірювання з використанням робочого макета спектрометра і джерел рентгенівського випромінювання, а також досліджені спектральні розподіли випромінювання реальних зразків ⁹⁹ᵐТc у спеціальній упаковці (скляній ампулі). Для Si-PIN-детектора товщиною 300 мкм спектр випромінювання складається з лінії ⁹⁹ᵐТc з енергією 140,5 кеВ і двох піків характеристичного рентгенівського випромінювання технеція. Розрахунок у GEANT4 показує узгодження активностей ⁹⁹ᵐТc, отриманих по реєстрації ХРВ і основної лінії. Запропоновано вимірювання концентрації технеція не тільки по лінії 140,5 кеВ, а й по випромінюванню ХРВ, що істотно збільшує швидкість набору даних. Методика экспресс-анализа предусматривает измерение спектров излучения медицинских радионуклидов детектирующим модулем на основе неохлаждаемого кремниевого планарного детектора и модулем типа «сцинтиллятор - кремниевый фотосенсор». Разработано спектрометрическое устройство для экспресс-анализа концентрации радионуклидов и проведено его макетирование, подтверждающее работоспособность устройства. Питание спектрометра-анализатора выполнено от USB-порта ПК (в том числе, ноутбука), что обеспечивает возможность автономной работы. Проведены тестовые измерения с использованием рабочего макета спектрометра и источников рентгеновского излучения, а также исследованы спектральные распределения излучения реальных образцов ⁹⁹ᵐТс в специальной упаковке (стеклянной ампуле). Для Si-PIN-детектора толщиной 300 мкм спектр излучения состоит из линии ⁹⁹ᵐТс с энергией 140,5 кэВ и двух пиков характеристичного рентгеновского излучения технеция. Расчет в GEANT4 показывает согласие активностей ⁹⁹ᵐТc, полученных по регистрации ХРИ и основной линии. Предложено измерение концентрации технеция не только по линии 140,5 кэВ, но и по излучению ХРИ, что существенно увеличивает скорость набора данных. 2017 Article Method for express determination of medical radionuclides ⁹⁹ᵐTc, ⁶⁷Cu concentration using spectrometer based on Si planar detector / O.S. Deiev, S.K. Kiprich, N.I. Maslov, V.D. Ovchinnik, M.Y. Shulika, G.P. Vasiliev, V.I. Yalovenko // Вопросы атомной науки и техники. — 2017. — № 6. — С. 117-121. — Бібліогр.: 14 назв. — англ. 1562-6016 PACS: 07.85.Fv, 61.80.Cb http://dspace.nbuv.gov.ua/handle/123456789/136208 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| collection |
DSpace DC |
| language |
English |
| topic |
Детекторы и детектирование ядерных излучений Детекторы и детектирование ядерных излучений |
| spellingShingle |
Детекторы и детектирование ядерных излучений Детекторы и детектирование ядерных излучений Deiev, O.S. Kiprich, S.K. Maslov, N.I. Ovchinnik, V.D. Shulika, M.Y. Vasiliev, G.P. Yalovenko, V.I. Method for express determination of medical radionuclides ⁹⁹ᵐTc, ⁶⁷Cu concentration using spectrometer based on Si planar detector Вопросы атомной науки и техники |
| description |
The method of express analysis provides the measurement of radiation spectra of medical radionuclides by a detection module based on an uncooled silicon planar detector and a "scintillator-silicon photosensor" type module. A spectrometric device for express analysis of radionuclide concentration has been developed and its prototyping has been carried out, confirming the operability of the device. The spectrometer analyzer is powered from the USB port of the PC (including a laptop) that provides the possibility of autonomous operation. Test measurements were carried out using the prototype of the spectrometer and X-ray sources, as well as spectral distributions of the radiation of real samples of ⁹⁹ᵐTc in a special container (glass ampoule). For a Si-PIN-detector with a thickness of 300 μm, the emission spectrum consists of a line of ⁹⁹ᵐTc with an energy of 140.5 keV and two peaks of the characteristic X-ray radiation (CXR) of technetium. The calculation in GEANT4 shows the matching of the ⁹⁹ᵐTc activities obtained from the registration of CXR and the main line. A measurement of the technetium concentration both by the 140.5 keV line and on the CXR radiation was proposed that significantly increases the speed of the data accumulation. |
| format |
Article |
| author |
Deiev, O.S. Kiprich, S.K. Maslov, N.I. Ovchinnik, V.D. Shulika, M.Y. Vasiliev, G.P. Yalovenko, V.I. |
| author_facet |
Deiev, O.S. Kiprich, S.K. Maslov, N.I. Ovchinnik, V.D. Shulika, M.Y. Vasiliev, G.P. Yalovenko, V.I. |
| author_sort |
Deiev, O.S. |
| title |
Method for express determination of medical radionuclides ⁹⁹ᵐTc, ⁶⁷Cu concentration using spectrometer based on Si planar detector |
| title_short |
Method for express determination of medical radionuclides ⁹⁹ᵐTc, ⁶⁷Cu concentration using spectrometer based on Si planar detector |
| title_full |
Method for express determination of medical radionuclides ⁹⁹ᵐTc, ⁶⁷Cu concentration using spectrometer based on Si planar detector |
| title_fullStr |
Method for express determination of medical radionuclides ⁹⁹ᵐTc, ⁶⁷Cu concentration using spectrometer based on Si planar detector |
| title_full_unstemmed |
Method for express determination of medical radionuclides ⁹⁹ᵐTc, ⁶⁷Cu concentration using spectrometer based on Si planar detector |
| title_sort |
method for express determination of medical radionuclides ⁹⁹ᵐtc, ⁶⁷cu concentration using spectrometer based on si planar detector |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| publishDate |
2017 |
| topic_facet |
Детекторы и детектирование ядерных излучений |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/136208 |
| citation_txt |
Method for express determination of medical radionuclides ⁹⁹ᵐTc, ⁶⁷Cu concentration using spectrometer based on Si planar detector / O.S. Deiev, S.K. Kiprich, N.I. Maslov, V.D. Ovchinnik, M.Y. Shulika, G.P. Vasiliev, V.I. Yalovenko // Вопросы атомной науки и техники. — 2017. — № 6. — С. 117-121. — Бібліогр.: 14 назв. — англ. |
| series |
Вопросы атомной науки и техники |
| work_keys_str_mv |
AT deievos methodforexpressdeterminationofmedicalradionuclides99mtc67cuconcentrationusingspectrometerbasedonsiplanardetector AT kiprichsk methodforexpressdeterminationofmedicalradionuclides99mtc67cuconcentrationusingspectrometerbasedonsiplanardetector AT maslovni methodforexpressdeterminationofmedicalradionuclides99mtc67cuconcentrationusingspectrometerbasedonsiplanardetector AT ovchinnikvd methodforexpressdeterminationofmedicalradionuclides99mtc67cuconcentrationusingspectrometerbasedonsiplanardetector AT shulikamy methodforexpressdeterminationofmedicalradionuclides99mtc67cuconcentrationusingspectrometerbasedonsiplanardetector AT vasilievgp methodforexpressdeterminationofmedicalradionuclides99mtc67cuconcentrationusingspectrometerbasedonsiplanardetector AT yalovenkovi methodforexpressdeterminationofmedicalradionuclides99mtc67cuconcentrationusingspectrometerbasedonsiplanardetector |
| first_indexed |
2025-07-10T00:51:46Z |
| last_indexed |
2025-07-10T00:51:46Z |
| _version_ |
1837219142809157632 |
| fulltext |
ISSN 1562-6016. ВАНТ. 2017. №6(112) 117
DETECTORS AND NUCLEAR RADIATION DETECTION
METHOD FOR EXPRESS DETERMINATION OF MEDICAL
RADIONUCLIDES
99m
Tc,
67
Cu CONCENTRATION USING
SPECTROMETER BASED ON Si PLANAR DETECTOR
O.S. Deiev, S.K. Kiprich, N.I. Maslov, V.D. Ovchinnik,
M.Y. Shulika, G.P. Vasiliev, V.I. Yalovenko
National Science Center “Kharkov Institute of Physics and Technology”, Kharkov, Ukraine
The method of express analysis provides the measurement of radiation spectra of medical radionuclides by a de-
tection module based on an uncooled silicon planar detector and a "scintillator-silicon photosensor" type module. A
spectrometric device for express analysis of radionuclide concentration has been developed and its prototyping has
been carried out, confirming the operability of the device. The spectrometer analyzer is powered from the USB port
of the PC (including a laptop) that provides the possibility of autonomous operation. Test measurements were car-
ried out using the prototype of the spectrometer and X-ray sources, as well as spectral distributions of the radiation
of real samples of
99m
Tc in a special container (glass ampoule). For a Si-PIN-detector with a thickness of 300 μm,
the emission spectrum consists of a line of
99m
Tc with an energy of 140.5 keV and two peaks of the characteristic X-
ray radiation (CXR) of technetium. The calculation in GEANT4 shows the matching of the
99m
Tc activities obtained
from the registration of CXR and the main line. A measurement of the technetium concentration both by the 140.5 keV
line and on the CXR radiation was proposed that significantly increases the speed of the data accumulation.
PACS: 07.85.Fv, 61.80.Cb
INTRODUCTION
Modern nuclear medicine uses radioactive isotopes
in the form of radiopharmaceuticals, which allow carry-
ing out various diagnostic and therapeutic procedures
[1, 2]. The most important radionuclide used in 80…90%
of the procedures is
99m
Tc. This isotope is formed during
the decay of the parent isotope
99
Mo [3, 4]. The
99m
Tc
isotope is separated by physicochemical means and used
as a radioactive label in various chemical compounds. A
perspective isotope is also
67
Cu. This isotope has a short
half-life and low-energy emission lines what reduces the
radiation dose on the patient's body.
The NSC KIPT developed the physical and techno-
logical basis for the production of
99
Мо/
99m
Тс [3, 4] and
67
Cu [5, 6] using the bremsstrahlung of an electron ac-
celerator. The obtained real pharmaceutical drug
99m
Tc
was contained in glass ampoules with a wall thickness
of ~ 1 mm. Due to the fact that the obtained pharmaceu-
ticals are of different activity, the production of such
drugs requires the determination of the concentration of
the medical radionuclide in a short time. For the express
analysis of the medical radionuclides
99m
Tc and
67
Cu
concentration a spectrometer analyzer with interchange-
able detection modules was developed in NSC KIPT.
One of the detection modules based on an uncooled
planar silicon detector, the second module is a scintilla-
tor-photodetector system.
The spectrometer-analyzer was powered from the
USB port of the PC (laptop) that provides the possibility
of autonomous operation.
1. RADIATION LINES
99m
Тс,
67
Cu
The half-life of
99m
Tc is 6.01 h, the energy and rela-
tive intensity of its main lines of gamma and X-ray radi-
ation show in Table 1 [7, 8]. The radiation of techneti-
um consists of the main line of 140.5 keV (the intensity
of the quantum yield per decay 89%) and several lines
of the CXR technetium. The K-lines of the CXR techne-
tium arise after the internal conversion of electrons from
the K shell and total quantum yield is of ~ 8.3% of the
main line intensity 140.5 keV. Kα lines have a yield
intensity per decay of 6.25%, Kβ 1.157%.
Table 1
Energy and intensities of the main lines of gamma
and X-rays for
99m
Тс
Gammas from
99m
Tc (6.01 h)
Eγ (keV) Iγ (%)
140.511 89
X-rays from
99m
Tc (6.01 h )
Eγ (keV) Iγ (%) Assignment
18.251 2.15 Tc Ka2
18.367 4.10 Tc Ka1
20.599 0.333 Tc Kb3
20.619 0.644 Tc Kb1
20.789 0.00357 Tc Kb5
21.005 0.146 Tc Kb2
21.042 0.0302 Tc Kb4
The half-life of
67
Cu is 61.83 h. The
67
Cu emission
spectra also consists of several lines (decay mode β
-
)
and is presented in Table 2.
Table 2
Energy and intensities of the main lines of gamma
and X-rays for
67
Cu
Gammas from
67
Cu (61.83 h )
Eγ (keV) Iγ (%)
91.266 7.0
93.311 16.1
184.577 48.7
X-rays from
67
Cu (61.83 h )
Eγ (keV) Iγ (%) Assignment
8.616 1.95 Zn Ka2
8.639 3.84 Zn Ka1
9.572 0.239 Zn K3
9.572 0.464 Zn K1
ISSN 1562-6016. ВАНТ. 2017. №6(112) 118
The low-energy CXR is strongly absorbed by the
walls of the glass ampoule and is not suitable for ex-
press analysis of the drug. Therefore, the detection of
67
Cu is detected by gamma radiation lines. The lines
with Eγ = 91.266 and 93.311 keV are detected by the Si-
PIN detector and line 184.577 keV – by the system of
CsI(Tl) scintillator – Si-PIN-photodiode.
2. SPECTROMETER-ANALYZER
FOR EXPRESS ANALYSIS OF MEDICAL
RADIONUCLIDES CONCENTRATION
99m
Tc
AND
67
Cu WITH REPLACEABLE
DETECTION MODULES
The sealed modules of uncooled planar silicon de-
tectors and read-out electronics developed and fabricat-
ed at the NSC KIPT showed high stability when using
in high-energy physics, nuclear physics experiments,
devices for monitoring the concentration of elements,
and in medical diagnostic devices [9 - 11].
In Fig. 1 two types of detection modules used in the
present work are presented, an uncooled silicon PIN
detector (on the left) and a detection system CsI(Tl)
scintillator a silicon PIN-photodiode (on the right).
Fig. 1. Two types of detection modules:
the uncooled Si-PIN detector (on the left)
and the detection system CsI(Tl) scintillator –
Si-PIN-photodiode (right)
A spectrometric channel based on an uncooled Si-
PIN detector of 300 μm thickness provides detection of
radiation in the energy range Eγ = 5...150 keV with a
resolution of FWHM = 1…1.2 keV. Radiation with an
energy Eγ > 50 keV is more efficiently registered with
the help of detection systems consisting of a scintillator
CsI(Tl) and a Si-PIN-photodiode. In [12 - 14] the effi-
ciency of quanta registration of different energies for
detecting modules based on an uncooled planar Si-
detector, as well as a scintillator-photodetector system,
was considered.
Fig. 2. Prototype of the spectrometer-analyzer for
the express analysis of the
99m
Tc activity consists
of sealed detector, preamplifier, module with
a spectrometric amplifier, ADС converter and PC
In Fig. 2 spectrometer-analyzer prototype for the fast
analysis of the concentration of
99m
Tc is shown. The
monitor shows the spectrum accumulation.
Fig. 3 shows the experimental emission spectrum of
a real pharmaceutical preparation
99m
Tc, placed in a
glass ampoule with a wall thickness of ~ 1 mm, ob-
tained by a Si-PIN-detector of 300 μm htickness.
Fig. 3. Experimental emission spectrum of the real
pharmaceutical preparation
99m
Tc, obtained by the Si –
PIN-detector of 300 μm thickness (blue curve).
Red curves the fitting of CXR peaks (Kα, Kβ)
and 140.5 keV
The emission spectrum consists of a main line of
140.5 keV, Compton distribution (49.8 keV edge),
and two CXR lines of technetium (with energy Kα =
18.36 and Kβ = 20.6 keV). Kα lines have a yield intensi-
ty per decay of 6.25%, Kβ 1.157% (Table 1). Each
emission line has its own absorption coefficient in me-
dia and its registration efficiency in Si detector. The
calculation in GEANT4 shows the agreement of the
99m
Tc activities obtained from the registration of CXR
and the main line. A measurement of the technetium
concentration both by the 140.5 keV line and on the
CXR radiation was proposed, what significantly in-
creases the speed of the data accumulation.
For experimental measurements the ratio of Kα / Кβ
was ~ 5.15…5.35 (the estimate from Table 1 gives a
ratio of ~ 5.4), and the ratio of the sum of CXR quanta
(Kα + Kβ) exceeded the sum of the quanta at 140.5 keV
peak at 15.2 times, what is close to the simulation re-
sults for the glass of 1 mm thickness.
The dependence of drug activity over the time was
measured. Figs. 4, 5 shows the experimental values of
drug activity measured at different times (red squares)
and the estimated activity rating with allowance for de-
cay (blue line).
Fig. 4. Experimental values of the activity of the drug
for the 140.5 keV line, measured at different times (red
squares) and calculated activity with allowance
for decay (blue line)
ISSN 1562-6016. ВАНТ. 2017. №6(112) 119
Fig. 5. Experimental values of drug activity
(the entire spectrum is summed in the interval
ΔE = 10…140.5 keV) measured at different times
(red squares) and calculated activity with allowance
for decay (blue line)
These two measurements showed the same decrease
in activity 1.45 times in 233 minutes. The speed of ac-
cumulation the entire spectrum in the energy range
ΔE = 10…140.5 keV exceeds the speed of dialing along
the line 140.5 keV by about 37 times. Calculations in
GEANT4 give approximately the same ratio of the reg-
istered integral spectrum to the baseline. This opens the
possibility of calibrating the spectrometer over the inte-
gral spectrum and significantly increases the speed of
the analysis.
3. CALCULATIONS OF THE INTENSITY
OF THE MAIN GAMMA LINE AND X-RAY
LINES IN GEANT4
Fig. 6 shows the visual representation in GEANT4
of the trajectories of gamma and X-ray quanta (green
lines) for a system: ampoule with liquid (cylinder, yel-
low), glass (red) and detector (Si, 300 µm, blue). For
simplicity, the trajectories of quanta are shown directed
to the area of the detector are normal to its surface.
Quanta arise randomly in the volume of a liquid.
Fig. 6. Visual presentation in GEANT4 of the trajecto-
ries of gamma and X-ray quanta (green lines)
for a system: ampoule with liquid (cylinder, yellow),
glass (red) and detector (Si, 300 µm, blue)
A feature of the passage of low energy quanta
through thin layers of matter is their strong absorption.
The trajectories of quanta in Fig. 6 are rectilinear, but
some of the quanta are absorbed in the glass and liquid,
and the quanta passing into the Si detector are only par-
tially registered in it. In GEANT4 the relative intensities
of the main gamma and X-ray lines registered in Si,
300 µm for
99m
Tc for various glass ampoule thicknesses
are calculated. The results are presented in Table 3.
Table 3
Energy and relative intensities of the main lines
of gamma and X-ray radiation registered in Si, 300 µm
for
99m
Tc for various glass thicknesses
of the ampoule
Еγ 0.2 mm 0.5 mm 1 mm 2 mm
18.36 24.79 18.83 11.52 5.41
20.6 3.95 3.27 2.33 1.43
140.5 1 1 1 1
As one can see from the data for 1 mm of glass, the
calculated increasing of the value of CXR quanta over
the main peak is ~14, what is close to the experimental-
ly measured value of ~15.2.
The results of calculations in GEANT4 of the rela-
tive intensities of the main emission lines of
99m
Tc for
various plastic materials of the exit window with a
thickness of 0.5 mm are presented in Table 4.
Table 4
Energy and relative intensities of the main lines
of gamma and X-ray emission registered in Si, 300 µm
for
99m
Tc for various materials of the output window,
thickness 0.5 mm (GEANT4)
Еγ Teflon Plexiglass Kapton
18.36 28.34 30.81 30.74
20.6 4.40 4.69 4.65
140.5 1 1 1
In the case of a thin plastic window, the increasing
of the number of CXR quanta over the main peak is
~ 35 times.
Note that excitation of CXR Tc and Mo by the main
line 140.5 keV is also possible. For the provisional
thickness Tc and Mo ~ 100 μm, the yield of CXR (Kα +
Kβ) in the full angle does not exceed 0.7% of the inten-
sity of the main line for Tc and 0.6% for Mo.
The line Kβ CXR Tc with an energy of 20.6 keV
may re-emit, exciting CXR Mo. This increases the pos-
sible amount of Mo CXR (Kα + Kβ) up to ~ 0.62% of
the intensity of the main line in solution Mo 50% / Tc
50% and thickness ~ 100 μm. One should take into ac-
count that K-lines of CXR Tc from the process of inter-
nal conversion of electrons together give a quanta yield
of ~ 8.3% of the intensity of the main line of 140.5 keV.
In such an estimate, the distorting effect of additional
CXR of technetium and molybdenum is ~ 1.32 / 8.3 =
16%. In pure solution the increase in CXR Tc is ~ 0.7 /
8.3 = 8%.
An analysis of the experimental spectrum gives the
CXR lines exactly to the energies 19.35 and 20.6 keV.
The Kα peak of the Mo line of 17.47 keV would be lo-
cated 13 channels to the left. Such a difference would be
fixed by the detection system. In addition, the ratio Kα /
Kβ for Tc would change noticeably. This fact means that
the amount of residual Mo is at least an order of magni-
tude smaller than the case considered.
ISSN 1562-6016. ВАНТ. 2017. №6(112) 120
4. MEASUREMENT OF THE
99m
Tc
ACTIVITY WITH A DETECTION MODULE
BASED ON THE SCINTILLATOR-
PHOTODETECTOR SYSTEM
The emission lines of the sources
241
Am,
57
Co,
99m
Тс
were measured by the detecting system of the scintilla-
tor CsI(Tl)-Si-PIN photodiode.
Fig. 7 shows the results of gamma-ray spectrum
measurements of the
241
Am source line with Eγ =
59.54 keV and
57
Co, Eγ = 122 keV. The size of the scin-
tillator CsI(Tl) is 5510 mm, Si-PIN-photodiode is
550.3 mm.
Fig. 7. Gamma spectrum of the
241
Am source
Eγ = 59.54 keV line and
57
Co, Eγ = 122 keV
Fig. 8 shows the results of gamma-ray spectrum
measurements of
99m
Tc the 140.5 keV line. The size of
the scintillator CsI(Tl) is 2210 mm, Si-PIN-
photodiode is 220.3 mm. Calculation of the drug ac-
tivity was carried out according to the number of counts
in the peak
99m
Tc. The processing is performed by fit-
ting the peak of 140.5 keV.
Fig. 8. The experimental gamma-ray spectrum
of
99m
Tc, the 140.5 keV line (blue curve). The red curve
is the fitting of the 140.5 keV peak in ORIGIN8
Comparative measurements of drug activity by three
spectrometers were performed: by High Purity Cooled
Germanium Detector (HPGe) Canberra, by Si-PIN-
detector and CsI(Tl)-Si photodiode system. Taking into
account the decrease in the
99m
Tc emission intensity
with time, all the results practically coincide. For exam-
ple, for 1 ml of the drug: HPGe gives the activity result
25,900,000 Bq; 300 µm Si-PIN photodiode
25,351,000 Bq in 4π, 2210 mm
3
CsI(Tl) – Si-PIN-
photodiode 25,971,000 Bq in total solid angle 4π. All
the results are calculated to the end of the bombardment
(EOB) time.
CONCLUSIONS
A spectrometer analyzer with replaceable detection
modules was developed in NSC KIPT for the express
analysis of medical radionuclides
99m
Tc,
67
Cu concentra-
tion. One of the detection modules is based on an un-
cooled planar Si-PIN-detector (300 μm), the second one
is based on a detection system CsI(Tl) scintillator – Si-
PIN-photodiode. The spectral distribution of radiation
of real samples of the pharmaceutical preparation
99m
Tc
in various experimental geometry was measured by two
detection systems.
The emission spectrum consists of a main line of
140.5 keV, Compton distribution (49.8 keV edge) and
two CXR lines of technetium (with energy Kα = 18.36
and Kβ = 20.6 keV).
The calculation in GEANT4 shows the agreement of
the
99m
Tc activities obtained from the registration of
CXR and the main line.
A measurement of the technetium concentration
both by the 140.5 keV line and by the CXR radiation
was proposed what significantly increases the speed of
the data accumulation.
In the case of a thin glass or plastic window, the in-
creasing of the value of CXR quanta over the main peak
is ~ 35 times.
Comparative measurements of drug activity by three
spectrometers were performed: HPGe, Si-PIN-detector
and CsI(Tl) – Si-photodiode system. Taking into ac-
count the decrease in the
99m
Tc emission intensity with
time, the results practically coincide.
REFERENCES
1. N.P. Dikiy, A.N. Dovbnya, S.V. Maryokhin,
V.L. Uvarov. On Efficiency of Medical & Biophysi-
cal Isotopes Production Using Electron Accelerator
// Problems of Atomic Science and Technology. Se-
ries “Nuclear Physics Investigations”. 1999, № 3
(34), р. 91-92.
2. V.Yu. Baranov. Isotopes: properties, application.
M.: Science “Fizmat. Lit.” 2005, p. 328 (in Russian).
3. N.P. Dikiy, A.N. Dovbnya, V.L. Uvarov. The fun-
damentals of
99m
Tc production cycle at electron ac-
celerator // Problems of Atomic Science and Tech-
nology. Series “Nuclear Physics Investigations”.
2004, № 1, p. 168-171.
4. L.I. Nikolaichuk, V.A. Popov, A.I. Tutubalin,
O.V. Krivchenko, A.G. Shepelev. Analyses on pro-
duction of
99
Mo and
99m
Tc isotopes for nuclear med-
icine // Problems of Atomic Sience and Technology.
Series “Nuclear Physics Investigations”. 2012,
№ 4(80), p. 160-162.
5. N.I. Ayzatsky, N.P. Dikiy, A.N. Dovbnya, et al. Fea-
tures of Cu-67 photonuclear production // Problems
of Atomic Science and Technology. Series “Nuclear
Physics Investigations”. 2008, № 3, p. 174-178.
6. N.I. Ayzatsky, N.P. Dikiy, A.N. Dovbnya, et al.
99
Mo and
67
Cu isotope yields under production con-
ditions of NSC KIPT electron accelerator KUT-30 //
Problems of Atomic Science and Technology. Series
“Nuclear Physics Investigations”. 2010, № 2,
p. 140-144.
ISSN 1562-6016. ВАНТ. 2017. №6(112) 121
7. The Lund/LBNL Nuclear Data Search,
http://nucleardata.nuclear.lu.se/toi/
8. National nuclear data center,
http://www.nndc.bnl.gov/
9. G.P. Vasilyev, V.K. Voloshin, S.K. Kiprich, et al.
Encapsulated modules of silicon detectors of ioniz-
ing radiation // Problems of Atomic Science and
Technology. Series “Nuclear Physics Investiga-
tions”. 2010, № 3, p. 200-204.
10. V.I. Kulibaba, N.I. Maslov, S.V. Naumov,
V.D. Ovchinnik, I.M. Prokhorets. Readout electron-
ics for multichannel detectors // Problems of Atomic
Science and Technology. Series “Nuclear Physics In-
vestigations”. 2001, № 5(39), p. 177-179.
11. N.I. Maslov. Physical and technological aspects of
creation and applications of silicon planar detectors
// Problems of Atomic Science and Technology.
2013, № 2(84), p. 165-171.
12. G.L. Bochek, O.S. Deiev, N.I. Maslov, V.K. Vo-
loshyn. X-ray lines relative intensity depending on
detector efficiency, foils and cases thickness for
primary and scattered spectra// Problems of Atomic
Science and Technology. Series “Nuclear Physics
Investigations”. 2011, № 3, p. 42-49.
13. G.P. Vasiliev, V.K. Voloshyn, O.S. Deiev, et al.
Measurement of Radiation Energy by Spectrometric
Systems Based on Uncooled Silicon Detectors //
Journal of Surface Investigation. X-ray, Synchrotron
and Neutron Techniques. 2014, v. 8, № 2, p. 391-
397.
14. G.P. Vasiliev, V.K. Voloshyn, O.S. Deiev, et al.
Radiation dose determination by dual channel spec-
trometr in energy range 0.005...1 MeV // Problems
of Atomic Science and Technology. Series “Nuclear
Physics Investigations”. 2012, № 4 (80), p. 205-209.
Article received 25.10.2017
СПОСОБ ЭКСПРЕССНОГО ОПРЕДЕЛЕНИЯ КОНЦЕНТРАЦИИ МЕДИЦИНСКИХ
РАДИОНУКЛИДОВ
99m
Tc,
67
Cu C ИСПОЛЬЗОВАНИЕМ СПЕКТРОМЕТРА
НА ОСНОВЕ Si-ПЛАНАРНОГО ДЕТЕКТОРА
А.С. Деев, С.К. Киприч, Н.И. Маслов, В.Д. Овчинник, М.Ю. Шулика, Г.П. Васильев, В.И. Яловенко
Методика экспресс-анализа предусматривает измерение спектров излучения медицинских радионукли-
дов детектирующим модулем на основе неохлаждаемого кремниевого планарного детектора и модулем типа
«сцинтиллятор кремниевый фотосенсор». Разработано спектрометрическое устройство для экспресс-
анализа концентрации радионуклидов и проведено его макетирование, подтверждающее работоспособность
устройства. Питание спектрометра-анализатора выполнено от USB-порта ПК (в том числе, ноутбука), что
обеспечивает возможность автономной работы. Проведены тестовые измерения с использованием рабочего
макета спектрометра и источников рентгеновского излучения, а также исследованы спектральные распреде-
ления излучения реальных образцов
99м
Тс в специальной упаковке (стеклянной ампуле). Для Si-PIN-
детектора толщиной 300 мкм спектр излучения состоит из линии
99m
Тс с энергией 140,5 кэВ и двух пиков
характеристичного рентгеновского излучения технеция. Расчет в GEANT4 показывает согласие активностей
99m
Тc, полученных по регистрации ХРИ и основной линии. Предложено измерение концентрации технеция
не только по линии 140,5 кэВ, но и по излучению ХРИ, что существенно увеличивает скорость набора дан-
ных.
СПОСІБ ЕКСПРЕСНОГО ВИЗНАЧЕННЯ КОНЦЕНТРАЦІЇ МЕДИЧНИХ РАДІОНУКЛІДІВ
99m
Tc,
67
Cu З ВИКОРИСТАННЯМ СПЕКТРОМЕТРА НА ОСНОВІ Si-ПЛАНАРНОГО ДЕТЕКТОРА
О.С. Деєв, С.К. Кіпріч, М.І. Маслов, В.Д. Овчинник, М.Ю. Шуліка, Г.П. Васильєв, В.І. Яловенко
Методика експрес-аналізу передбачає вимір спектрів випромінювання медичних радіонуклідів детекту-
ючим модулем на основі неохолоджуваного кремнієвого планарного детектора і модулем типу «сцинтиля-
тор кремнієвий фотосенсор». Розроблено спектрометричний пристрій для експрес-аналізу концентрації
радіонуклідів і проведено його макетування, що підтверджує працездатність пристрою. Живлення спектро-
метра-аналізатора виконано від USB-порту ПК (в тому числі, ноутбука), що забезпечує можливість автоно-
мної роботи. Проведено тестові вимірювання з використанням робочого макета спектрометра і джерел рент-
генівського випромінювання, а також досліджені спектральні розподіли випромінювання реальних зразків
99m
Тc у спеціальній упаковці (скляній ампулі). Для Si-PIN-детектора товщиною 300 мкм спектр випроміню-
вання складається з лінії
99m
Тc з енергією 140,5 кеВ і двох піків характеристичного рентгенівського випро-
мінювання технеція. Розрахунок у GEANT4 показує узгодження активностей
99m
Тc, отриманих по реєстрації
ХРВ і основної лінії. Запропоновано вимірювання концентрації технеція не тільки по лінії 140,5 кеВ, а й по
випромінюванню ХРВ, що істотно збільшує швидкість набору даних.
http://nucleardata.nuclear.lu.se/toi/
|