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Showing 7 results for Cyclotron
P. Rowshanfarzad, A.r. Jalilian, M. Sabet, Volume 2, Issue 1 (6-2004)
Abstract
Background : Selenium-73 (T 1/2 =7.1h) and Selenium-75 (T 1/2 =119.8d) are useful radioisotopes in many research fields. The wide ranges of applications of these radioisotopes arose great interest for their production. Simultaneous production of 73 Se and 75 Se is more cost-effective and less time-consuming. Materials and Methods : 73 As (p, 3n) 73 Se and 75 As (p,n) 75 Se reactions were determined as the best choices for the production of 73 Se and 75 Se radioisotopes, according to the present facilities and conditions. The bombardment was performed by 30 MeV protons in Cyclone 30-IBA accelerator. ALICE and SRIM nuclear codes were used to determine the best energy and target thicknesses. Targets were specifically designed for simultaneous production of the radioisotopes as two consecutive pellets. Chemical processing was performed by no carrier added solvent extraction method. Radio-TLC was performed on polymer backed silica gel. A colorimetricmethod was used for chemical quality control. Radionuclidic quality control of the inal products was carried out by gamma spectroscopy with HPGe detector. Results: The production yield was 5.3 mCi/µAh for 73 Se and 50 µCi/µAh and 678 µCi/µAh for 75 Se in the first and second pellets respectively. The specific activity of 73 Se was 1.06 mCi/ml and that of 75 Se was 135.6 µCi/ml after one hour of proton bombardment with a current of 5µA. The isotopic purity of 73 Se was 99% in the first pellet and that of 75 Se was 100% in the second, just after the end of bombardment. A 0.04 ppm colorimetric method showed no traces of arsenic in the final product. Conclusion : The quick and inexpensive procedure used in this research, resulted in high yields,high chemical and high isotopic purity for both radioisotopes. It can be considered as the method of choice for simultaneous production of 73 Se and 75 Se. Iran . J. Radiat. Res., 2004 2 (1): 45-51
A.r. Jalilian, P. Rowshanfarzad, J. Moafian, M. Kamali-Dehghan, M. Mirzaii, Volume 2, Issue 3 (12-2004)
Abstract
Background: Copper-64 (T1/2=12.7 h) is an important radionuclide used both in PET imaging and therapy. [64Cu]-pyruvaldehyde-bis (N4-methylthiosemicarbazone) ([64Cu]-PTSM) is one of the most famous copper radiopharmaceuticals with unique specifications (suitable half life, stability, etc.). The wide range of 64Cu applications arouse great interest for its production. Materials and Methods: Cu-64 was produced via the 68Zn (p, α n) 64Cu nuclear reaction and isolated from the irradiated target by a two-step chemical method. [64Cu]-PTSM was prepared using in-house made PTSM ligand and [64Cu] cuprous acetate. The complex formation parameter s (time, temperature, concentration and elution methods) were determined carefully. Results: Copper-64 was prepared in chloride form (≈200 mCi, >95% chemical yield at 180 μA for 1.1 h irradiation, radionuclidic purity >96%, copper-67 as impurity). The solution of 64Cu-PTSM was prepared in >80% radiochemical yield and more than 98% radiochemical purity. Quality controls and stability tests were performed for the final solution. Conclusion: [64Cu]-PTSM was prepared at the radiopharmaceutical scales with high quality and potential to be used in therapeutic/imaging centers. Iran . J. Radiat. Res., 2004 2 (3): 107-115
P. Rowshanfarzad, A.r. Jalilian, M. Sabet2, M. Akhlaghi, Volume 2, Issue 3 (12-2004)
Abstract
Background: 66Ga (t1/2=9.49 h, β+: 4.153 MeV, γ: 511, 834, 1039, 2752 keV) has a wide range of applications in different fields of medical sciences. Production of 66Ga became one of our main interests, according to its increasing applications in nuclear medicine, particularly in PET imaging. Materials and Methods: 66 Zn (p,n)66Ga reaction was determined as the best choice for the production of 66Ga, according to the present facilities and conditions. The bombardment was performed by 15 MeV protons in Cyclone 30-IBA accelerator with a current intensity of 180 μA for 67 min. ALICE nuclear code and SRIM nuclear program were used to determine the optimum energy and target thickness. Targets were prepared by electroplating of 66Zn (>95%) on a copper backing. Chemical processing was performed by a no carrier added method consisting of ion exchange chromatography and liquid-liquid extraction. Anion exchange chromatography was used for the recovery of target material. Quality control of the product was carried out in two steps of chemical and radionuclidic purity control. Results: The activity of 66Ga was 2.41 Ci at the end of bombardment (E.O.B.) and the production yield was 12.04 mCi/μAh. The chemical separation yield was 93% and the yield of chemica l recovery of the target material was 97%. Quality control tests showed a radionuclidic purity of more than 97% and the amounts of chemical impurities were in accordance with standard levels. Discussion: Our production yield was comparable with previous reports given in the literature. The chemical separation method used in this research was simple and brought up acceptable results. So, this process can be considered as one of the best choices for the production of 66Ga. Iran . J. Radiat. Res., 2004 2 (3): 149-158
Dr A.r. Jalilian, M. Sadeghi, Y.y. Kamrani, A. Bahrami, Volume 4, Issue 1 (6-2006)
Abstract
Background: Due to interesting tumor imaging properties of bis-thiosemicarbazones, [103Pd]-di-acetyl-bis (N4-methylthiosemicarbazone) ([103Pd] ATSM2) was prepared according to the analogy of radio copper homologues.
Materials and Methods: Palladium-103 (T1/2=16.96 d) was produced via the 103Rh (p,n) 103Pd nuclear reaction with proton energy 18 MeV. The final activity was eluted in form of Pd (NH4)2Cl2 in order to react with bis-thiosemicarbazones to yield [103Pd]-labeled compounds. Chemical purity of the final product was confirmed to be below the accepted limits by polarography. The labeled compound was purified by reverse phase column chromatography using C18 plus Sep-Pak. The partition co-efficient of the final complexes were determined. The initial physico-chemical properties of the labeled compounds were compared to those of their copper homologues.
Results: Radiochemical purity of more than 99% using RTLC was obtained (specific activity of about 12500-13000 Ci/mol). The stability of the tracer was checked in final product and human serum, at 37C up to 48h.
Conclusion: The labeled compound prepared in this study is probably one of the few new 103pd-radiolabeled compounds which have a potential for future biological studies, regarding its suitable physicochemical stability.
Dr. A. R. Jalilian, L. Mirsadegh, R. Haji-Hosseini, S. Rajabifar, F. Bolurinovin, Volume 4, Issue 4 (3-2007)
Abstract
Background: In order to obtain an anti-CD20
conjugate to be used in future therapeutic studies with
therapeutic radioisotopes, 67Ga-labeled antibody was
prepared as a model of metal chelated
immunoconjugate for preliminary dosimetric and
biodistribution studies. Materials and Methods:
Rituximab was labeled with [67Ga]-gallium chloride
after residulation with freshly prepared cyclic DTPAdianhydride.
The best results of the conjugation were
obtained by the addition of 1 ml of a rituximab
pharmaceutical solution (5 mg/ml, in phosphate
buffer, pH=8) to a glass tube pre-coated with DTPAdianhydride
(0.01 mg) at 25|o|C with continuous mild
stirring for 30 min. The final isotonic 67Ga-DTPArituximab
complex was checked by gel electrophoresis
for radiolysis/chemolysis control. Radio-TLC was
performed to ensure the formation of only one
species. Preliminary in vivo studies in normal rat
model were performed to determine the
biodistribution of the radioimmunoconjugate up to 6
hours. Results: Radio-thin layer chromatography
showed an overall radiochemical purity of 96-99% at
optimized conditions (specific activity =300-500
MBq/mg, labeling efficiency 77%). Gel electrophoresis
showed no protein cleavage after radiolabeling.
Conclusion: Preliminary in vivo studies in normal rat
model showed [67Ga]-DTPA-rituximab is a good probe
for bio-dosimetry of therapeutic rituximab conjugates.
Iran. J. Radiat. Res., 2007 4 (4): 187-193
T. Kakavand, Dr. M. Sadeghi, K. Kamali Moghaddam, S. Shokri Bonab, B. Fateh, Volume 5, Issue 4 (3-2008)
Abstract
Background: Iodine-123 (123I) is regarded as one of the best radionuclides for in vivo medical studies using single-photon emission computed tomography (SPECT) due to its suitable physical property. Materials and Methods: To design a new system in order to replace cryogenically solidified xenon target by the gas one, some necessary calculations are needed to be done such as finding the excitation functions variation of the production reactions, thick target yield of 123I production, etc. The computer codes Alice91 and SRIM have been used as a calculation tools. Results: According to the suggested design, a conical shaped irradiation vessel made of copper with thickness of 1mm, outlet diameter of 1 cm, 5 cm length and 12° angle at summit can be fixed inside a liquid nitrogen housing chamber. The 124Xe gas was sent to the inside of this very cold conical trap and eventually deposited on its surface in solid form. Calculation showed that during bombardment with 17- 28 MeV proton energy, the thickness of solidified xenon layer remained about 0.28 mm. Conclusion: The production yield of 123I can be predicted to be around 150 mCi/µAh.
Dr. A.r. Jalilian, M. Tajik, H. Zandi, J. Garousi, F. Bolourinovin, Volume 7, Issue 2 (9-2009)
Abstract
Background: Oxytocin (OT) is a paracrine hormone with various biological activities and many sex organs in both sexes, as well as many tumor cells have shown to have related receptors. In this study the development of a receptor imaging tracer for possible tumor imaging has been described. Materials and Methods: OT was successively labeled with [67Ga]-gallium chloride after conjugation with freshly prepared cyclic DTPA-dianhydride. The best results of the conjugation were obtained by the addition of 1 ml of a OT pharmaceutical solution (2 mg/ml, in phosphate buffer, pH=8) to a glass tube pre-coated with DTPA-dianhydride (0.02 mg) at 25°C with continuous mild stirring for 30 min. Radiochemical purity (RCP) of the labeled compound was determined, using RTLC and ITLC followed by stability tests and animal biodistribution studies. Results: Radiolabeling took about 60 minutes with a RCP higher than 98 % at optimized conditions (specific activity = 1000 Ci/mM, labeling efficiency 80%). The stability of the tracer at room temperature was significant, up to an hour. Preliminary in vivo studies in normal female rat model showed ovary/blood and ovary/muscle ratio uptake of the tracer in 60 minutes to be 4.53 and 9.18, respectively. The result was consistent with the reported OT receptor distribution in normal female mammals. Conclusion: The radiolabeled oxytocin, prepared in this study, was a possible fast acting tracer for OT receptor imaging studies however, more studies are required to determine the best imaging conditions especially in larger mammal animals. Iran. J. Radiat. Res., 2009 7 (2): 105-111
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