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Nagai, Yasuki*; Kawabata, Masako*; Hashimoto, Shintaro; Tsukada, Kazuaki; Hashimoto, Kazuyuki*; Motoishi, Shoji*; Saeki, Hideya*; Motomura, Arata*; Minato, Futoshi; Ito, Masatoshi*
Journal of the Physical Society of Japan, 91(4), p.044201_1 - 044201_10, 2022/04
Times Cited Count:2 Percentile:42.15(Physics, Multidisciplinary)Recently, Lu is considered as one of the most important medical RIs for treating neuroendocrine tumors. A plan to produce
Lu with high purity by using enriched
Yb samples with irradiation of deuteron beams in accelerators has been discussed. However, since the other Yb isotopes contained in the Yb sample interacts with deuterons, Lu isotopes other than
Lu are produced as impurities. Since the purity of
Lu is important for medical use, a method to evaluate the impurity of Lu has been required. In this study, we proposed a new method to estimate production yields of each Lu isotopes in Yb samples with arbitrary isotopic compositions by using excitation functions of Yb(
)Lu reactions and the particle transport calculation code PHITS. The method plays an important role in discussing the isotopic composition of enriched samples to produce high-purity
Lu using accelerators.
Kawabata, Masako*; Motoishi, Shoji*; Ota, Akio*; Motomura, Arata*; Saeki, Hideya*; Tsukada, Kazuaki; Hashimoto, Shintaro; Iwamoto, Nobuyuki; Nagai, Yasuki*; Hashimoto, Kazuyuki*
Journal of Radioanalytical and Nuclear Chemistry, 330(3), p.913 - 922, 2021/12
Times Cited Count:7 Percentile:75.12(Chemistry, Analytical)Both Cu and
Cu are promising radionuclides in nuclear medicine. Production yields of these radionuclides were quantified by irradiating 55.4 g of natural zinc with accelerator neutrons. Clinically suitable
Cu and
Cu yields were estimated by experimental based numerical simulations using 100 g of enriched
Zn and
Zn, respectively, and elevated neutron fluxes from 40 MeV, 2 mA deuterons. A combined thermal- and resin-separation method was developed to isolate
Cu and
Cu from zinc, resulting in 73% separation efficiency and 97% zinc recovery. Such methods can provide large scale production of
Cu and
Cu for clinical applications.
Tsukada, Kazuaki; Nagai, Yasuki*; Hashimoto, Shintaro; Minato, Futoshi; Kawabata, Masako*; Hatsukawa, Yuichi*; Hashimoto, Kazuyuki*; Watanabe, Satoshi*; Saeki, Hideya*; Motoishi, Shoji*
Journal of the Physical Society of Japan, 89(3), p.034201_1 - 034201_7, 2020/03
Times Cited Count:2 Percentile:21.38(Physics, Multidisciplinary)We found anomalously large yields of Ga,
Ga,
Zn and
Cu by neutron irradiation on a
ZnO sample in a polyethylene shield. Neutron beams are generated from the
Be(
) reaction for 50 MeV deuterons. The yields obtained were more than 20 times larger than those in the unshielded sample. On the other hand, the yields of
Ga,
Ga,
Zn and
Cu from a metallic
Zn sample and the yields of
Cu,
Ni and
Zn from the
ZnO and
Zn samples were almost insensitive to the shield conditions. This finding would provide us a unique capability of accelerator neutrons to simultaneously produce a large amount of several radioisotopes, including proton induced reaction products, by using a single sample. The experimental data were compared with the yields estimated by using the Particle and Heavy Ion Transport code System and the result was discussed.
Hatsukawa, Yuichi*; Hayakawa, Takehito*; Tsukada, Kazuaki; Hashimoto, Kazuyuki*; Sato, Tetsuya; Asai, Masato; Toyoshima, Atsushi; Tanimori, Toru*; Sonoda, Shinya*; Kabuki, Shigeto*; et al.
PLOS ONE (Internet), 13(12), p.e0208909_1 - e0208909_12, 2018/12
Times Cited Count:3 Percentile:29.51(Multidisciplinary Sciences)Imaging of Tc radioisotope was conducted using an electron tracking-Compton camera (ETCC).
Tc emits 204, 582, and 835 keV
rays, and was produced in the
Mo(p,n)
Tc reaction with a
Mo-enriched target. The recycling of the
Mo-enriched molybdenum trioxide was investigated, and the recycled yield of
Mo was achieved to be 70% - 90%. The images were obtained with each of the three
rays. Results showed that the spatial resolution increases with increasing
-ray energy, and suggested that the ETCC with high-energy
-ray emitters such as
Tc is useful for the medical imaging of deep tissue and organs in the human body.
Tsukada, Kazuaki; Nagai, Yasuki*; Hashimoto, Kazuyuki*; Kawabata, Masako*; Minato, Futoshi; Saeki, Hideya*; Motoishi, Shoji*; Ito, Masatoshi*
Journal of the Physical Society of Japan, 87(4), p.043201_1 - 043201_5, 2018/04
Times Cited Count:10 Percentile:59.63(Physics, Multidisciplinary)Nishinaka, Ichiro*; Yokoyama, Akihiko*; Washiyama, Koshin*; Makii, Hiroyuki; Hashimoto, Kazuyuki*
Journal of Radioanalytical and Nuclear Chemistry, 314(3), p.1947 - 1965, 2017/12
Times Cited Count:2 Percentile:19.24(Chemistry, Analytical)Production cross sections of iodine, tellurium and antimony radionuclides in the 24-59 MeV Li +
Sn reaction have been measured by the conventional stacked foil technique with
-ray spectrometry. Excitation functions of the production cross sections were compared with a statistical model calculation. The contributions of complete and incomplete fusion in the production of observed radionuclides are discussed from the view points of production routes in the nuclide chart and decays for iodine, tellurium and antimony nuclides. The integral yields of
I were deduced from the calculated excitation functions in the
Li induced reactions on Sn isotopes in view of the production of medically important
I. The results are discussed by comparing with literature values in the other reactions.
Sugo, Yumi*; Hashimoto, Kazuyuki*; Kawabata, Masako*; Saeki, Hideya*; Sato, Shunichi*; Tsukada, Kazuaki; Nagai, Yasuki*
Journal of the Physical Society of Japan, 86(2), p.023201_1 - 023201_3, 2017/02
Times Cited Count:14 Percentile:67.59(Physics, Multidisciplinary)Cu produced by the
Zn(
)
Cu reaction was used for the first time to determine the biodistribution of
CuCl
in colorectal tumor-bearing mice. High uptake of
Cu was observed in the tumor as well as in the liver and kidney which are the major organs for copper metabolism. The result showing
Cu accumulation in the tumor suggests that
CuCl
can be a potential radionuclide agent for cancer radiotherapy. It would also encourage further studies on the therapeutic effect in small animals using an increased dose of
Cu produced by the
Zn(
)
Cu reaction using intense neutrons available at present.
Nishinaka, Ichiro; Yokoyama, Akihiko*; Washiyama, Koshin*; Maeda, Eita*; Watanabe, Shigeki; Hashimoto, Kazuyuki; Ishioka, Noriko; Makii, Hiroyuki; Toyoshima, Atsushi; Yamada, Norihiro*; et al.
Journal of Radioanalytical and Nuclear Chemistry, 304(3), p.1077 - 1083, 2015/06
Times Cited Count:9 Percentile:60.04(Chemistry, Analytical)Production cross sections of astatine isotopes At in the 29-57 MeV
Li induced reaction with
Pb target have been measured by
- and
-ray spectrometry. Excitation functions of production cross sections have been compared with a statistical model calculation to study the reaction mechanism of
Li +
Pb. Considerably small experimental cross sections of
At and
At compared with the calculation were clearly observed at incident energies higher than 44 MeV, indicating that the effects of breakup reaction play a role. A chemical separation of astatine from an irradiated lead target has been studied with a dry-distillation method. A complementary way to produce astatine isotopes has been developed.
Hashimoto, Kazuyuki; Nagai, Yasuki; Kawabata, Masako; Sato, Nozomi*; Hatsukawa, Yuichi; Saeki, Hideya; Motoishi, Shoji*; Ota, Masayuki; Konno, Chikara; Ochiai, Kentaro; et al.
Journal of the Physical Society of Japan, 84(4), p.043202_1 - 043202_4, 2015/04
Times Cited Count:8 Percentile:52.64(Physics, Multidisciplinary)Watanabe, Satoshi; Hashimoto, Kazuyuki; Ishioka, Noriko
JAEA-Review 2014-050, JAEA Takasaki Annual Report 2013, P. 102, 2015/03
Watanabe, Satoshi; Hashimoto, Kazuyuki; Ishioka, Noriko
Journal of Radioanalytical and Nuclear Chemistry, 303(2), p.1519 - 1521, 2015/02
Times Cited Count:10 Percentile:64.00(Chemistry, Analytical)As basic studies of bifunctional chelating agent for Lu-labeled antibodies,
Lu complexation of DOTA and DTPA was investigated by the addition of competing metals, Ca(II), Fe(II) and Zn(II). From comparison of competing metals, the inhibition by competing metals on the
Lu complexation was in the order of Ca(II)
Fe(II)
Zn(II) and Ca(II)
Zn(II)
Fe(II) as DOTA and DTPA, respectively. For comparison between DOTA and DTPA, the susceptibility to the inhibition on
Lu complexation by all the three competing metals was DTPA
DOTA. Therefore, it was found that DTPA is advantageous for
Lu complexation compared with DOTA in the presence of Ca(II), Fe(II) and Zn(II), and that the elimination of Fe from
Lu solution is especially effective because the
Lu complexation of DTPA is highly inhibited by Fe(II).
Hatsukawa, Yuichi; Hashimoto, Kazuyuki; Tsukada, Kazuaki; Sato, Tetsuya; Asai, Masato; Toyoshima, Atsushi; Nagai, Yasuki; Tanimori, Toru*; Sonoda, Shinya*; Kabuki, Shigeto*; et al.
Journal of Radioanalytical and Nuclear Chemistry, 303(2), p.1283 - 1285, 2015/02
Times Cited Count:2 Percentile:17.42(Chemistry, Analytical)Technetium-99m (Tc) is used in radioactive medical diagonostic tests, for example as a radioactive tracer that medical equipment can detect in the human body. It is well suited to the role because it emits readily detectable 141 keV
rays, and its half-life is 6.01 hours (meaning that about 94% of it decays to technetium-99 in 24 hours). There are at least 31 commonly used radiopharmaceuticals based on technetium-99m for imaging and functional studies of the brain, myocardium, thyroid, lungs, liver, gallbladder, kidneys, skeleton, blood, and tumors. Recent years, with the develop-ment of the Compton camera which can realize high position resolution, technetium isotopes emitting high energy
-rays are required. In this study, technetium-95m which emits some
rays around 800 keV was produced by the
Mo(p,n)
Tc reaction.
Kawabata, Masako; Nagai, Yasuki; Hashimoto, Kazuyuki; Saeki, Hideya; Motoishi, Shoji*; Sato, Nozomi*; Ota, Akio*; Shiina, Takayuki*; Kawauchi, Yukimasa*
Journal of the Physical Society of Japan, 84(2), p.023201_1 - 023201_4, 2015/02
Times Cited Count:6 Percentile:44.95(Physics, Multidisciplinary)Tc for medical use can be separated by thermochromatography from a molten
MoO
sample. Effect of moist oxygen gas on the
Tc release from molten
MoO
samples was investigated using a
Mo/
Tc generator.
Mo was produced with
Mo(n,2n)
Mo. A new phenomenon has been observed: release rate, separation- and recovery-efficiencies of
Tc were higher in the moist oxygen gas than those in the dry oxygen gas. The present result is a significant progress towards the stable production of a high quality
Tc from a molten MoO
sample with high separation efficiency. The result would also give us a new insight into the interaction between the moist oxygen gas and the molten MoO
.
Watanabe, Satoshi; Hashimoto, Kazuyuki; Watanabe, Shigeki; Iida, Yasuhiko*; Hanaoka, Hirofumi*; Endo, Keigo*; Ishioka, Noriko
Journal of Radioanalytical and Nuclear Chemistry, 303(1), p.935 - 940, 2015/01
Times Cited Count:11 Percentile:66.88(Chemistry, Analytical)Nagai, Yasuki; Kawabata, Masako; Sato, Nozomi; Hashimoto, Kazuyuki; Saeki, Hideya; Motoishi, Shoji*
Journal of the Physical Society of Japan, 83(8), p.083201_1 - 083201_4, 2014/07
Times Cited Count:10 Percentile:57.57(Physics, Multidisciplinary)Hashimoto, Kazuyuki; Fujisaki, Saburo*
Hoshasen To Sangyo, (136), p.17 - 21, 2014/06
no abstracts in English
Nagai, Yasuki; Hashimoto, Kazuyuki
Nihon Butsuri Gakkai-Shi, 69(6), p.370 - 375, 2014/06
In Japan, about 0.9 million diagnostic procedures are carried out using Tc, the daughter nuclide of
Mo with a half-life of 66 h, separated from
Mo; all
Mo radioisotopes are imported. Most of
Mo has been produced by the fission reaction of highly enriched
U in research reactors in the world. However, a number of incidents of the reactors caused the shortage of
Mo worldwide, which triggered widespread discussions on the reliable supply of
Mo. We proposed a new route to produce a large quantity of high quality
Mo using fast neutrons from an accelerator.
Watanabe, Satoshi; Hashimoto, Kazuyuki; Ishioka, Noriko
JAEA-Review 2013-059, JAEA Takasaki Annual Report 2012, P. 97, 2014/03
Hashimoto, Kazuyuki; Nagai, Yasuki
Comprehensive Biomedical Physics, Vol.8, p.219 - 227, 2014/00
Radionuclides for medical use are produced in nuclear reactors and in accelerators. The thermal neutron fluxes in nuclear reactors are several orders of magnitude higher than those of other neutron sources, such as accelerator neutrons. Hence, nuclear reactors have been playing important roles in the production of large quantity of medical radionuclides with their half-lives longer than several days. In accelerators, medical radionuclides with their half-lives longer than several minutes are produced. Recent progresses in accelerator technology as well as targetry technology, however, could enable one to obtain high-flux bremsstrahlung and intense energetic accelerator neutrons, and thereby to study new routes to produce medical radionuclides.
Nagai, Yasuki; Hashimoto, Kazuyuki; Hatsukawa, Yuichi; Saeki, Hideya; Motoishi, Shoji; Sonoda, Nozomi; Kawabata, Masako; Harada, Hideo; Kin, Tadahiro*; Tsukada, Kazuaki; et al.
Journal of the Physical Society of Japan, 82(6), p.064201_1 - 064201_7, 2013/06
Times Cited Count:43 Percentile:85.20(Physics, Multidisciplinary)