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Frank Roesch - One of the best experts on this subject based on the ideXlab platform.
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Production of the positron-emitting Radionuclide 68Ga: the radiochemical scheme of Radionuclide Generator 68Ge → 68Ga
Chemical Bulletin of Kazakh National University, 2018Co-Authors: Ayagoz Baimukhanova, Elena T. Chakrova, D. Karaivanov, Ján Kozempel, Frank Roesch, Dmitriy V. FilosofovAbstract:68Ga (T1 / 2 = 68 min) in complexes with peptides is used in positron emission tomography for diagnostics of neuroendocrine tumors. The most promising strategy for 68Ga production is usage of the Radionuclide Generator 68Ge → 68Ga. In this research, the sorption behavior of Ge(IV) and Ga (III) has been studied. The distribution coefficients (Kd) of Ge(IV) on the anion exchange (Dowex 1×8) and cation exchange (Dowex 50×8) resins in various ethanedioic and hydrochloric acid solutions were determined. For each ion exchange resin, four series of measurements were carried out, in which the concentration of oxalic acid was fixed (0.001 M, 0.003 M, 0.005 M, 0.01 M), and the concentrations of hydrochloric acid ranged from 0 to 3 M. Based on the distribution coefficients, the chemical scheme of the Radionuclide Generator 68Ge → 68Ga has been developed. The chemical system is based on the anion exchange resin Dowex 1×8 and mixture of 0.005 M C2H2O4 / 0.33 M HCl. Several types of the Generators with direct and reverse mode of elution were tested and the optimal scheme was determined. Elution of the Generators was performed once a day with 8 ml of 0.005 M C2H2O4 / 0.33 M HCl solution. The 68Ga yield and the 68Ge breakthrough are comparable for all the systems.
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scandium 44 benefits of a long lived pet Radionuclide available from the 44 ti 44 sc Generator system
Current Radiopharmaceuticals, 2012Co-Authors: Frank RoeschAbstract:(44)Ti/(44)Sc Radionuclide Generators are of interest for molecular imaging. The 3.97 hours half-life of (44)Sc and its high positron branching of 94.27% may stimulate the application of (44)Sc-labeled PET radiopharmaceuticals. This review describes the current status of (44)Ti production, (44)Ti/(44)Sc Radionuclide Generator development, post-processing of Generator eluates towards medical application, identification of ligands adequate to Sc(III) co-ordination chemistry, proof-of-principle labeling of (44)Sc-DOTA-octreotides, investigation of in vitro and in vivo parameters, and initial applications for molecular imaging - both in small animals and humans.
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Maturation of a Key Resource - The Germanium-68/Gallium-68 Generator: Development and New Insights
Current radiopharmaceuticals, 2012Co-Authors: Frank RoeschAbstract:Ge/ 68 Ga Radionuclide Generators have been investigated for almost fifty years, since the cyclotron- independent availability of positron emitting 68 Ga via the 68 Ge/ 68 Ga system had always attracted researches working in basic nuclear chemistry as well as radiopharmaceutical chemistry. However, it took decades and generations of research (and researchers) to finally reach a level of 68 Ge/ 68 Ga Radionuclide Generator designs adequate to the modern requirements of radiometal labelling chemistry. Nevertheless, most of the existing commercial Generator systems address aspects of 68 Ge breakthrough and safe synthesis of 68 Ga radiopharmaceuticals by adopting eluate post-processing technologies. Among the strategies to purify 68 Ga eluates, the cation exchange based version is relevant in terms of purification effi- ciency. In addition, it offers more options towards further developments of 68 Ga radiopharmaceuticals. Today, one may expect that the 68 Ge/ 68 Ga Radionuclide Generator systems could contribute to the clinical impact of nuclear medicine diag- noses for PET similar to the established 99 Mo/ 99m Tc Generator system for SPECT. The exciting perspective for the 68 Ge/ 68 Ga Radionuclide Generator system, in turn, asks for systematic chemical, radiochemical, technological and radio- pharmaceutical efforts, to guarantee reliable, highly-efficient and medically approved 68 Ge/ 68 Ga Generator systems.
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Scandium-44: benefits of a long-lived PET Radionuclide available from the (44)Ti/(44)Sc Generator system.
Current radiopharmaceuticals, 2012Co-Authors: Frank RoeschAbstract:(44)Ti/(44)Sc Radionuclide Generators are of interest for molecular imaging. The 3.97 hours half-life of (44)Sc and its high positron branching of 94.27% may stimulate the application of (44)Sc-labeled PET radiopharmaceuticals. This review describes the current status of (44)Ti production, (44)Ti/(44)Sc Radionuclide Generator development, post-processing of Generator eluates towards medical application, identification of ligands adequate to Sc(III) co-ordination chemistry, proof-of-principle labeling of (44)Sc-DOTA-octreotides, investigation of in vitro and in vivo parameters, and initial applications for molecular imaging - both in small animals and humans.
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a methodical 68ga labelling study of do2a butyl l tyrosine 2 with cation exchanger post processed 68ga practical aspects of radiolabelling
Contrast Media & Molecular Imaging, 2011Co-Authors: Carsten Burchardt, Patrick J. Riss, Frank RoeschAbstract:Positron emission tomography (PET) with 68Ga is a fast-growing field in molecular imaging, both in research and in clinical routine. The availability of 68Ga via the 68Ge/68Ga Radionuclide Generator facilitates the development and production of radiopharmaceuticals independent of a cyclotron. The presented work shows a complete 68Ga labelling study exemplified on [68Ga]DO2A-(butyl- l-tyrosine)2, a potential tumour tracer for PET. A methodical sequence is followed to optimize the 68Ga-labelling reaction. Practical aspects are described and the different parameters contributing to the labelling yield are demonstrated. The influence of temperature, time, amount of labelling precursor and pH value on the radiochemical yields is demonstrated. A conventional heating method is compared with microwave irradiation as an alternative labelling method. Finally, purification of 68Ga-labelled compounds via solid-phase extraction and quality control is shown. The procedure described in this manuscript may serve as a guideline for optimizing 68Ga labelling reactions. Copyright © 2011 John Wiley & Sons, Ltd.
Harbans L. Sharma - One of the best experts on this subject based on the ideXlab platform.
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Development of a high performance zinc-62/copper-62 Radionuclide Generator for positron emission tomography
European Journal of Nuclear Medicine, 1992Co-Authors: Jamal Zweit, Robert Goodall, Gerard A. Potter, John W. Babich, Harbans L. SharmaAbstract:Clinical utilisation of positron emission tomography could be enhanced by the availability of shortlived Radionuclides derived from Generator systems. The zinc-62/copper-62 combination is one such system which could be used as a source for a number of copper-62 radiopharmaceuticals. We have developed and optimised a high activity (5.6 GBq, 150 mCi) zinc-62/copper-62 Generator to provide ^62CU in a form that is suitable for direct labelling of pyruvaldehyde-bis-( N ^4-methylthiosemicarbazone)-copper(II), Cu(PTSM). The distribution coefficients of Zn(II) and Cu(II) between anion-exchange resin and various hydrochloric acid/organic solvent mixtures were measured. Based on these measurements a Generator eluent of 0.3 M HCl/40% ethanol provided ^62CU in >90% yield in a 3-ml volume. A very low ^62Zn breakthrough of less than 3×10^−7% was achieved. Copper-PTSM was successfully labelled with the no-carrier-added ^62Cu eluent directly from the Generator with 94% radiochemical yield.
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development of a high performance zinc 62 copper 62 Radionuclide Generator for positron emission tomography
European Journal of Nuclear Medicine and Molecular Imaging, 1992Co-Authors: Jamal Zweit, Robert Goodall, Gerard A. Potter, John W. Babich, Harbans L. SharmaAbstract:Clinical utilisation of positron emission tomography could be enhanced by the availability of shortlived Radionuclides derived from Generator systems. The zinc-62/copper-62 combination is one such system which could be used as a source for a number of copper-62 radiopharmaceuticals. We have developed and optimised a high activity (5.6 GBq, 150 mCi) zinc-62/copper-62 Generator to provide 62CU in a form that is suitable for direct labelling of pyruvaldehyde-bis-(N4-methylthiosemicarbazone)-copper(II), Cu(PTSM). The distribution coefficients of Zn(II) and Cu(II) between anion-exchange resin and various hydrochloric acid/organic solvent mixtures were measured. Based on these measurements a Generator eluent of 0.3 M HCl/40% ethanol provided 62CU in >90% yield in a 3-ml volume. A very low 62Zn breakthrough of less than 3×10−7% was achieved. Copper-PTSM was successfully labelled with the no-carrier-added 62Cu eluent directly from the Generator with 94% radiochemical yield.
Jamal Zweit - One of the best experts on this subject based on the ideXlab platform.
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A new Radionuclide Generator for positron emission tomography: Development of cerium-134/lanthanum-134 system
The Journal of Nuclear Medicine, 1994Co-Authors: Jamal Zweit, M. Doyley, P. CarnochanAbstract:Positron emitting radiopharmaceuticals labelled with Generator-produced Radionuclides could expand the use of PET imaging. The Ce-134/La-134 pair is a potential source of PET radiopharmaceuticals due to the favourable decay of both Radionuclides. This Generator produces the positron emitting (62%) La-134 with a 6.7 min half-life that is well suited to PET perfusion imaging. The half-life (3.2d) of Ce-134 gives the Generator a shelf-life comparable to that of the Mo-99/Tc-99m system. The parent Radionuclide Ce-134 was produced by irradiation of a natural lanthanum oxide target with 61 MeV protons. La-134 was separated from the target by anion-exchange on AG1x8 (nitrate) column. Development of the Generator was investigated through evaluation of several inorganic adsorbents and eluents. The influence of eluent pH, flow rate and column size on the adsorption of Ce(III/IV) and La(III) onto alumina, tin dioxide and manganese dioxide were studied. The thick target yield of Ce-134 is 148MBq (4mCi)/{mu}Ah with a batch yield of 3GBq. Using a lml manganese dioxide column and a 0.9M sodium chloride (pH 7.5) eluent at a flow rate of 0.7M./min, the Ce-134 was completely adsorbed while La-134 was eluted with a 70% yield in a 1.5ml volume. The Ce-134 breakthrough was not detectable after 20more » elutions. The feasibility of a new PET Generator has been demonstrated.« less
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a new Radionuclide Generator for positron emission tomography development of cerium 134 lanthanum 134 system
The Journal of Nuclear Medicine, 1994Co-Authors: Jamal Zweit, M. Doyley, P. CarnochanAbstract:Positron emitting radiopharmaceuticals labelled with Generator-produced Radionuclides could expand the use of PET imaging. The Ce-134/La-134 pair is a potential source of PET radiopharmaceuticals due to the favourable decay of both Radionuclides. This Generator produces the positron emitting (62%) La-134 with a 6.7 min half-life that is well suited to PET perfusion imaging. The half-life (3.2d) of Ce-134 gives the Generator a shelf-life comparable to that of the Mo-99/Tc-99m system. The parent Radionuclide Ce-134 was produced by irradiation of a natural lanthanum oxide target with 61 MeV protons. La-134 was separated from the target by anion-exchange on AG1x8 (nitrate) column. Development of the Generator was investigated through evaluation of several inorganic adsorbents and eluents. The influence of eluent pH, flow rate and column size on the adsorption of Ce(III/IV) and La(III) onto alumina, tin dioxide and manganese dioxide were studied. The thick target yield of Ce-134 is 148MBq (4mCi)/{mu}Ah with a batch yield of 3GBq. Using a lml manganese dioxide column and a 0.9M sodium chloride (pH 7.5) eluent at a flow rate of 0.7M./min, the Ce-134 was completely adsorbed while La-134 was eluted with a 70% yield in a 1.5ml volume. The Ce-134 breakthrough was not detectable after 20more » elutions. The feasibility of a new PET Generator has been demonstrated.« less
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Development of a high performance zinc-62/copper-62 Radionuclide Generator for positron emission tomography
European Journal of Nuclear Medicine, 1992Co-Authors: Jamal Zweit, Robert Goodall, Gerard A. Potter, John W. Babich, Harbans L. SharmaAbstract:Clinical utilisation of positron emission tomography could be enhanced by the availability of shortlived Radionuclides derived from Generator systems. The zinc-62/copper-62 combination is one such system which could be used as a source for a number of copper-62 radiopharmaceuticals. We have developed and optimised a high activity (5.6 GBq, 150 mCi) zinc-62/copper-62 Generator to provide ^62CU in a form that is suitable for direct labelling of pyruvaldehyde-bis-( N ^4-methylthiosemicarbazone)-copper(II), Cu(PTSM). The distribution coefficients of Zn(II) and Cu(II) between anion-exchange resin and various hydrochloric acid/organic solvent mixtures were measured. Based on these measurements a Generator eluent of 0.3 M HCl/40% ethanol provided ^62CU in >90% yield in a 3-ml volume. A very low ^62Zn breakthrough of less than 3×10^−7% was achieved. Copper-PTSM was successfully labelled with the no-carrier-added ^62Cu eluent directly from the Generator with 94% radiochemical yield.
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development of a high performance zinc 62 copper 62 Radionuclide Generator for positron emission tomography
European Journal of Nuclear Medicine and Molecular Imaging, 1992Co-Authors: Jamal Zweit, Robert Goodall, Gerard A. Potter, John W. Babich, Harbans L. SharmaAbstract:Clinical utilisation of positron emission tomography could be enhanced by the availability of shortlived Radionuclides derived from Generator systems. The zinc-62/copper-62 combination is one such system which could be used as a source for a number of copper-62 radiopharmaceuticals. We have developed and optimised a high activity (5.6 GBq, 150 mCi) zinc-62/copper-62 Generator to provide 62CU in a form that is suitable for direct labelling of pyruvaldehyde-bis-(N4-methylthiosemicarbazone)-copper(II), Cu(PTSM). The distribution coefficients of Zn(II) and Cu(II) between anion-exchange resin and various hydrochloric acid/organic solvent mixtures were measured. Based on these measurements a Generator eluent of 0.3 M HCl/40% ethanol provided 62CU in >90% yield in a 3-ml volume. A very low 62Zn breakthrough of less than 3×10−7% was achieved. Copper-PTSM was successfully labelled with the no-carrier-added 62Cu eluent directly from the Generator with 94% radiochemical yield.
Frank Rösch - One of the best experts on this subject based on the ideXlab platform.
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Radiolabelling and preliminary evaluation of 68Ga-tetrapyrrole derivatives as potential tracers for PET.
Nuclear medicine and biology, 2012Co-Authors: Frederic Zoller, Patrick J. Riss, Franz-peter Montforts, Debra K. Kelleher, Elisabeth Eppard, Frank RöschAbstract:article i nfo Tetrapyrroles are multisided natural products which are of relevance in clinical medicine. Owing to their specific accumulation in tumour tissue, porphyrins, metalloporphyrins and chlorins have been used as in photodynamic therapy and optical imaging. Moreover, their specific uptake into inflammatory atheromatous plaques via LDL endocytosis has been reported. The present study is concerned with the synthesis of 68 Ga labelled porphyrin derivatives and an in vitro assessment of the utility of radiotracers in positron emission tomography. A set of five porphyrin derivatives were labelled using 68 Ga from a commercially obtained Radionuclide Generator. Dedicated post-processing of the Generator eluate was conducted to allow for labelling in aqueous media and also under anhydrous conditions. Challenge studies and incubation in human serum confirmed the stability of the tracers. Plasma protein binding was investigated in order to confirm the presence of freely diffusible radioligand in plasma. A preliminary microPET study in a tumour-bearing rat resulted in a clear visualisation of the tumour.
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a 44ti 44sc Radionuclide Generator for potential application of 44sc based pet radiopharmaceuticals
Radiochimica Acta, 2010Co-Authors: D V Filosofov, Natalia Loktionova, Frank RöschAbstract:44 Ti/ 44 Sc Radionuclide Generators are of interest for molecular imaging. The 3.97 h half-life of 44 Sc and its high positron branching of 94% may stimulate the application of 44 Sc labelled PET radiopharmaceuticals. However, both 44 Ti production and 44 Ti/ 44 Sc Generator design represent challenges for basic radiochemistry. About 5 mCi (185 MBq) of 44 Ti were obtained via the Sc(p, 2n) nuclear reaction. 44 Ti was separated from 1.5 g of massive scandium targets in multi-step procedures, including exchange chromatography on cation exchange resin (AG 50W-X8, 200-400 mesh, H + -form). In order to design a robust 44 Ti/ 44 Sc Generator concept, distribution coefficients of Ti(IV) and Sc(III) on both AG 1-X8 (200-400 mesh, Cl - -form) and AG 50W-X8 (200-400 mesh, H + -form) resins eluted with HCl and HCl/H 2 C 2 O 4 solution of various concentrations were investigated systematically. Optimal conditions for efficient separations of both Radionuclides have been determined for AG 1-X8 resin and mixtures of 0.07 M HCl and 0.005 M H 2 C 2 O 4 . A 5 mCi Generator was prepared on an AG 1-X8 column (H = 150 mm, D = 3 mm, V 0 = 0.55 mL). The system achieved elution of 180 MBq 44 Sc in 20 mL of eluate solution. The breakthrough of 44 Ti is 90 Bq. This corresponds to an excellent separation factor of 2 x 10 6 . In the context of long-term stability of 44 Ti/ 44 Sc Generators, a "reverse" type of washing steps after each elution using 0.07 M HCl/0.005 M H 2 C 2 O 4 mixtures appeared to be essential.
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A 44Ti/44Sc Radionuclide Generator for potential application of 44Sc-based PET-radiopharmaceuticals
Radiochimica Acta, 2010Co-Authors: D V Filosofov, Natalia Loktionova, Frank RöschAbstract:44 Ti/ 44 Sc Radionuclide Generators are of interest for molecular imaging. The 3.97 h half-life of 44 Sc and its high positron branching of 94% may stimulate the application of 44 Sc labelled PET radiopharmaceuticals. However, both 44 Ti production and 44 Ti/ 44 Sc Generator design represent challenges for basic radiochemistry. About 5 mCi (185 MBq) of 44 Ti were obtained via the Sc(p, 2n) nuclear reaction. 44 Ti was separated from 1.5 g of massive scandium targets in multi-step procedures, including exchange chromatography on cation exchange resin (AG 50W-X8, 200-400 mesh, H + -form). In order to design a robust 44 Ti/ 44 Sc Generator concept, distribution coefficients of Ti(IV) and Sc(III) on both AG 1-X8 (200-400 mesh, Cl - -form) and AG 50W-X8 (200-400 mesh, H + -form) resins eluted with HCl and HCl/H 2 C 2 O 4 solution of various concentrations were investigated systematically. Optimal conditions for efficient separations of both Radionuclides have been determined for AG 1-X8 resin and mixtures of 0.07 M HCl and 0.005 M H 2 C 2 O 4 . A 5 mCi Generator was prepared on an AG 1-X8 column (H = 150 mm, D = 3 mm, V 0 = 0.55 mL). The system achieved elution of 180 MBq 44 Sc in 20 mL of eluate solution. The breakthrough of 44 Ti is 90 Bq. This corresponds to an excellent separation factor of 2 x 10 6 . In the context of long-term stability of 44 Ti/ 44 Sc Generators, a "reverse" type of washing steps after each elution using 0.07 M HCl/0.005 M H 2 C 2 O 4 mixtures appeared to be essential.
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a 140nd 140pr Radionuclide Generator based on physico chemical transitions in 140pr complexes after electron capture decay of 140nd dota
Radiochimica Acta, 2007Co-Authors: Konstantin Zhernosekov, D V Filosofov, Syed M. Qaim, Frank RöschAbstract:140 Nd was produced by irradiations of CeO 2 and Pr 2 O 3 targets leading to nat Ce( 3 He,xn) 140 Nd and 141 Pr(p,2n) 140 Nd nuclear reactions. The practical yield of 140 Nd at EOB in the former reaction over the energy range of E3 He = 33.5 → 0 MeV amounted to 3.5 MBq/μA h and in the latter reaction over the energy range of E p = 18.6 → 16.2 MeV to 15.5 MBq/μA h. These values correspond to about 41% and 60% of the respective theoretical values. Successful separations of the Radionuclide were performed by means of cation-exchange chromatography resulting in decontamination factors of ≥ 10 8 and ≥ 7 × 10 5 for the cerium and praseodymium target materials, respectively. With the no-carrier-added 140 Nd obtained, an efficient 140 Nd/ 140 Pr Radionuclide Generator system was developed and evaluated. The principle of the radiochemical separation is based on physico-chemical transitions (hot-atom effects) of the daughter 140 Pr following the electron decay process of 140 Nd. The parent Radionuclide 140 Nd(III) is quantitatively adsorbed on a solid phase matrix in the form of 140 Nd-DOTA-conjugated complexes. The daughter nuclide 140 Pr is generated in an ionic species and is easily separated using low volumes of various aqueous eluents. The elution yield is at least 93%, if an optimized eluent, such as DTPA solution is applied. The system remains stable at least over three half-lives of 140 Nd, with high radiolytic stability and low 140 Nd breakthrough. This Radionuclide Generator system 140 Nd (T 1/2 = 3.37 d) provides the short-lived positron-emitting radiolanthanide 140 Pr (T 1/2 = 3.4 min) for molecular imaging using positron emission tomography (PET).
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A 140Nd/140Pr Radionuclide Generator based on physico-chemical transitions in 140Pr complexes after electron capture decay of 140Nd-DOTA
Radiochimica Acta, 2007Co-Authors: Konstantin Zhernosekov, D V Filosofov, Syed M. Qaim, Frank RöschAbstract:140 Nd was produced by irradiations of CeO 2 and Pr 2 O 3 targets leading to nat Ce( 3 He,xn) 140 Nd and 141 Pr(p,2n) 140 Nd nuclear reactions. The practical yield of 140 Nd at EOB in the former reaction over the energy range of E3 He = 33.5 → 0 MeV amounted to 3.5 MBq/μA h and in the latter reaction over the energy range of E p = 18.6 → 16.2 MeV to 15.5 MBq/μA h. These values correspond to about 41% and 60% of the respective theoretical values. Successful separations of the Radionuclide were performed by means of cation-exchange chromatography resulting in decontamination factors of ≥ 10 8 and ≥ 7 × 10 5 for the cerium and praseodymium target materials, respectively. With the no-carrier-added 140 Nd obtained, an efficient 140 Nd/ 140 Pr Radionuclide Generator system was developed and evaluated. The principle of the radiochemical separation is based on physico-chemical transitions (hot-atom effects) of the daughter 140 Pr following the electron decay process of 140 Nd. The parent Radionuclide 140 Nd(III) is quantitatively adsorbed on a solid phase matrix in the form of 140 Nd-DOTA-conjugated complexes. The daughter nuclide 140 Pr is generated in an ionic species and is easily separated using low volumes of various aqueous eluents. The elution yield is at least 93%, if an optimized eluent, such as DTPA solution is applied. The system remains stable at least over three half-lives of 140 Nd, with high radiolytic stability and low 140 Nd breakthrough. This Radionuclide Generator system 140 Nd (T 1/2 = 3.37 d) provides the short-lived positron-emitting radiolanthanide 140 Pr (T 1/2 = 3.4 min) for molecular imaging using positron emission tomography (PET).
D V Filosofov - One of the best experts on this subject based on the ideXlab platform.
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172 Hf → 172 Lu Radionuclide Generator Based on a Reverse-Tandem Separation Scheme
Radiochemistry, 2018Co-Authors: Jakhongir Dadakhanov, N A Lebedev, A. I. Velichkov, D. V. Karaivanov, A. E. Baimukhanova, N. T. Temerbulatova, D V FilosofovAbstract:The distribution coefficients of Hf(IV) and Lu(III) between Dowex 50W×8 cation exchanger or Dowex 1×8 anion exchanger and mixed HCl–H2C2O4 solutions and between Dowex 50W×8 cation exchanger or Dowex 1×8 anion exchanger and citric acid solutions were determined. A number of modifications of the 172Hf → 172Lu Generator, based on reverse separation schemes, were examined. Systems consisting of an anion-exchange resin and a solution of appropriate organic acid were taken as a chemical basis of the Generator. Irreversible sorption of 172Lu in Generator columns was studied. The optimum operation mode of the 172Hf → 172Lu Generator based on the reverse-tandem scheme with periodic transfer of the parent Radionuclide into the liquid phase was determined.
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172 hf 172 lu Radionuclide Generator based on a reverse tandem separation scheme
Radiochemistry, 2018Co-Authors: N A Lebedev, Jakhongir Dadakhanov, A. I. Velichkov, D. V. Karaivanov, A. E. Baimukhanova, N. T. Temerbulatova, D V FilosofovAbstract:The distribution coefficients of Hf(IV) and Lu(III) between Dowex 50W×8 cation exchanger or Dowex 1×8 anion exchanger and mixed HCl–H2C2O4 solutions and between Dowex 50W×8 cation exchanger or Dowex 1×8 anion exchanger and citric acid solutions were determined. A number of modifications of the 172Hf → 172Lu Generator, based on reverse separation schemes, were examined. Systems consisting of an anion-exchange resin and a solution of appropriate organic acid were taken as a chemical basis of the Generator. Irreversible sorption of 172Lu in Generator columns was studied. The optimum operation mode of the 172Hf → 172Lu Generator based on the reverse-tandem scheme with periodic transfer of the parent Radionuclide into the liquid phase was determined.
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Utilization of (p, 4n) reaction for 86 Zr production with medium energy protons and development of a 86 Zr → 86 Y Radionuclide Generator
Journal of Radioanalytical and Nuclear Chemistry, 2018Co-Authors: Ayagoz Baimukhanova, D. Karaivanov, Ján Kozempel, Valery Radchenko, Atanaska Pavlova Marinova, Victoria Brown, Vasily Karandashev, Paul Schaffer, D V FilosofovAbstract:Utilization of (p, 4n) reaction channel for the production of medical Radionuclides became very attractive with commercial availability of medium energy cyclotrons. Significantly higher yields and radionuclidic purity may open new perspectives for several novel and some of the Radionuclides previously have not been considered due to production difficulties. In present work, we show the proof-of-principle study on the production of 86Y for Positron Emission Tomography imaging via Radionuclide Generator 86Zr → 86Y. Production suitability of 86Zr from natural yttrium target and radiochemical separation strategies were tested. In addition, two Generator systems were proposed and evaluated.
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utilization of p 4n reaction for 86 zr production with medium energy protons and development of a 86 zr 86 y Radionuclide Generator
Journal of Radioanalytical and Nuclear Chemistry, 2018Co-Authors: Ayagoz Baimukhanova, D. Karaivanov, Ján Kozempel, Valery Radchenko, Atanaska Pavlova Marinova, Victoria Brown, Vasily Karandashev, Paul Schaffer, D V FilosofovAbstract:Utilization of (p, 4n) reaction channel for the production of medical Radionuclides became very attractive with commercial availability of medium energy cyclotrons. Significantly higher yields and radionuclidic purity may open new perspectives for several novel and some of the Radionuclides previously have not been considered due to production difficulties. In present work, we show the proof-of-principle study on the production of 86Y for Positron Emission Tomography imaging via Radionuclide Generator 86Zr → 86Y. Production suitability of 86Zr from natural yttrium target and radiochemical separation strategies were tested. In addition, two Generator systems were proposed and evaluated.
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a 44ti 44sc Radionuclide Generator for potential application of 44sc based pet radiopharmaceuticals
Radiochimica Acta, 2010Co-Authors: D V Filosofov, Natalia Loktionova, Frank RöschAbstract:44 Ti/ 44 Sc Radionuclide Generators are of interest for molecular imaging. The 3.97 h half-life of 44 Sc and its high positron branching of 94% may stimulate the application of 44 Sc labelled PET radiopharmaceuticals. However, both 44 Ti production and 44 Ti/ 44 Sc Generator design represent challenges for basic radiochemistry. About 5 mCi (185 MBq) of 44 Ti were obtained via the Sc(p, 2n) nuclear reaction. 44 Ti was separated from 1.5 g of massive scandium targets in multi-step procedures, including exchange chromatography on cation exchange resin (AG 50W-X8, 200-400 mesh, H + -form). In order to design a robust 44 Ti/ 44 Sc Generator concept, distribution coefficients of Ti(IV) and Sc(III) on both AG 1-X8 (200-400 mesh, Cl - -form) and AG 50W-X8 (200-400 mesh, H + -form) resins eluted with HCl and HCl/H 2 C 2 O 4 solution of various concentrations were investigated systematically. Optimal conditions for efficient separations of both Radionuclides have been determined for AG 1-X8 resin and mixtures of 0.07 M HCl and 0.005 M H 2 C 2 O 4 . A 5 mCi Generator was prepared on an AG 1-X8 column (H = 150 mm, D = 3 mm, V 0 = 0.55 mL). The system achieved elution of 180 MBq 44 Sc in 20 mL of eluate solution. The breakthrough of 44 Ti is 90 Bq. This corresponds to an excellent separation factor of 2 x 10 6 . In the context of long-term stability of 44 Ti/ 44 Sc Generators, a "reverse" type of washing steps after each elution using 0.07 M HCl/0.005 M H 2 C 2 O 4 mixtures appeared to be essential.
