Base de dados : MEDLINE
Pesquisa : D01.268.271.100.900 [Categoria DeCS]
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  1 / 1608 MEDLINE  
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[PMID]:29251897
[Au] Autor:Alashrah S; El-Taher A
[Ti] Título:Assessment of natural radioactivity level and radiation hazards in soil samples of Wadi Al-Rummah Qassim province, Saudi Arabia.
[So] Source:J Environ Biol;37(5):985-81, 2016 09.
[Is] ISSN:0254-8704
[Cp] País de publicação:India
[La] Idioma:eng
[Ab] Resumo:The present work deals with estimation and distribution of natural radionuclides in 40 soil samples collected from Wadi Al-Rummah (Qassim part) Central Saudi Arabia. Estimations were carried out using NaI (Tl) gamma-ray spectrometer. Activity concentrations ranged from 5.3 to 45.0 Bq kg-1, from 4.3 to 33.8 Bq kg-1 and from 38 Bq kg-1 to 273.1 Bq kg-1 for 226Ra, 232Th and 40K, respectively. The average activity concentrations of 226Ra, 232Th and 40K in soil samples was 15.5 Bq kg-1, 14.1 Bq kg-1 and 143.1 Bq kg-1. The results of this study were compared with other studies around the world. Radiation hazard parameters such as radium equivalent activity, annual dose, external hazard were calculated and compared with the recommended levels quoted from International Commission on Radiological Protection (ICRP-60) and United Nations Scientific Committee on the Effects of Atomic Radiation UNSCEAR reports.
[Mh] Termos MeSH primário: Poluição Ambiental
Radioisótopos de Potássio/química
Rádio (Elemento)/química
Poluentes Radioativos do Solo
Tório/química
[Mh] Termos MeSH secundário: Rádio (Elemento)/análise
Arábia Saudita
[Pt] Tipo de publicação:RESEARCH SUPPORT, NON-U.S. GOV'T; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Potassium Radioisotopes); 0 (Soil Pollutants, Radioactive); 60YU5MIG9W (Thorium); W90AYD6R3Q (Radium)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180222
[Lr] Data última revisão:
180222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171219
[St] Status:MEDLINE


  2 / 1608 MEDLINE  
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[PMID]:29398044
[Au] Autor:Cinelli G; Tondeur F; Dehandschutter B
[Ad] Endereço:European Commission, Joint Research Centre, Directorate G, Nuclear Safety & Security, Via Enrico Fermi 2749, I-21027 Ispra, VA, Italy. Electronic address: giorgia.cinelli@ec.europa.eu.
[Ti] Título:Mapping potassium and thorium concentrations in Belgian soils.
[So] Source:J Environ Radioact;184-185:127-139, 2018 Apr.
[Is] ISSN:1879-1700
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The European Atlas of Natural Radiation developed by the Joint Research Centre (JRC) of the European Commission includes maps of potassium K and thorium Th. With several different databases available, including data (albeit not calibrated) from an airborne survey, Belgium is a favourable case for exploring the methodology of mapping for these natural radionuclides. Harmonized databases of potassium and thorium in soil were built by radiological (not airborne) and geochemical data. Using this harmonized database it was possible to calibrate the data from the airborne survey. Several methods were used to perform spatial interpolation and to smooth the data: moving average (MA) without constraint, or constrained by soil class and by geological unit. Overall, there was a reasonable agreement between the maps on a 1 × 1 km grid obtained with the two datasets (airborne data and harmonized soil data) with all the methods. The agreement was better when the maps are reduced to a 10 km × 10 km grid used for the European Atlas of Natural Radiation. The best agreement was observed with the MA constrained by geological unit.
[Mh] Termos MeSH primário: Radioisótopos de Potássio/análise
Monitoramento de Radiação
Poluentes Radioativos do Solo/análise
Tório/análise
[Mh] Termos MeSH secundário: Bélgica
Solo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Potassium Radioisotopes); 0 (Soil); 0 (Soil Pollutants, Radioactive); 60YU5MIG9W (Thorium)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180206
[St] Status:MEDLINE


  3 / 1608 MEDLINE  
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[PMID]:29367087
[Au] Autor:Hegedus M; Tóth-Bodrogi E; Jónás J; Somlai J; Kovács T
[Ad] Endereço:Institute of Radiochemistry and Radioecology, University of Pannonia, 10 Egyetem Str., H-8200, Veszprém, Hungary.
[Ti] Título:Mobility of Th and Po in red mud.
[So] Source:J Environ Radioact;184-185:71-76, 2018 Apr.
[Is] ISSN:1879-1700
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The valorization of industrial by-products such as red mud became a tempting opportunity, but the understanding of the risks involved is required for the safe utilization of these products. One of the risks involved are the elevated levels of radionuclides (in the 100-1300 Bq/kg range for both the U and  Th decay chains, but usually lower than 1000 Bq/kg, which is the recommended limit for excemption or clearance according to the EU BSS released in 2013) in red mud that can affect human health. There is no satisfactory answer for the utilization of red mud; the main current solution is still almost exclusively disposal into a landfill. For the safe utilization and deposition of red mud, it is important to be able to assess the leaching behaviour of radionuclides. Because there is no commonly accepted measurement protocol for testing the leaching of radionuclides in the EU a combined measurement protocol was made and tested based on heavy metal leaching methods. The leaching features of red mud were studied by methods compliant with the MSZ-21470-50 Hungarian standard, the CEN/TS 14429 standard and the Tessier sequential extraction method for Th and Po. The leached solutions were taken to radiochemical separation followed by spontaneous deposition for Po and electrodeposition for Th. The 332 ±â€¯33 Bq/kg Th content was minimally mobile, 1% became available for distilled water 1% and 6% for Lakanen-Erviö solution; the Tessier extraction showed minimal mobility in the first four steps, while more than 85% remained in the residue. The Po measurements had a severe disturbing effect in many cases, probably due to large amounts of iron present in the red mud, from the 310 ±â€¯12 Bq/kg by aqua regia digestion, distilled water mobilized 23%, while Lakanen-Erviö solution mobilized ∼13%. The proposed protocol is suitable for the analysis of Th and Po leaching behaviour.
[Mh] Termos MeSH primário: Resíduos Industriais/análise
Polônio/análise
Monitoramento de Radiação
Resíduos Radioativos/análise
Tório/análise
[Mh] Termos MeSH secundário: Hungria
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Industrial Waste); 0 (Radioactive Waste); 60YU5MIG9W (Thorium); DQY03U61EJ (Polonium)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180126
[St] Status:MEDLINE


  4 / 1608 MEDLINE  
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[PMID]:29272318
[Au] Autor:Mastren T; Radchenko V; Hopkins PD; Engle JW; Weidner JW; Copping R; Brugh M; Nortier FM; Birnbaum ER; John KD; Fassbender ME
[Ad] Endereço:Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America.
[Ti] Título:Separation of 103Ru from a proton irradiated thorium matrix: A potential source of Auger therapy radionuclide 103mRh.
[So] Source:PLoS One;12(12):e0190308, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Ruthenium-103 is the parent isotope of 103mRh (t1/2 56.1 min), an isotope of interest for Auger electron therapy. During the proton irradiation of thorium targets, large amounts of 103Ru are generated through proton induced fission. The development of a two part chemical separation process to isolate 103Ru in high yield and purity from a proton irradiated thorium matrix on an analytical scale is described herein. The first part employed an anion exchange column to remove cationic actinide/lanthanide impurities along with the majority of the transition metal fission products. Secondly, an extraction chromatographic column utilizing diglycolamide functional groups was used to decontaminate 103Ru from the remaining impurities. This method resulted in a final radiochemical yield of 83 ± 5% of 103Ru with a purity of 99.9%. Additionally, measured nuclear reaction cross sections for the formation of 103Ru and 106Ru via the 232Th(p,f)103,106Ru reactions are reported within.
[Mh] Termos MeSH primário: Rênio/química
Radioisótopos de Rutênio/isolamento & purificação
Tório/isolamento & purificação
[Mh] Termos MeSH secundário: Prótons
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Protons); 0 (Ruthenium Radioisotopes); 0 (Ruthenium-103); 60YU5MIG9W (Thorium); 7440-15-5 (Rhenium)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180116
[Lr] Data última revisão:
180116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171223
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0190308


  5 / 1608 MEDLINE  
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[PMID]:29182917
[Au] Autor:Ribeiro FCA; Silva JIR; Lima ESA; do Amaral Sobrinho NMB; Perez DV; Lauria DC
[Ad] Endereço:Institute of Radiation Protection and Dosimetry (IRD), Brazilian National Commission on Nuclear Energy (CNEN), Av. Salvador Allende, s/n, Barra da Tijuca, Rio de Janeiro, RJ 22783-127 Brazil. Electronic address: fribeiro@ird.gov.br.
[Ti] Título:Natural radioactivity in soils of the state of Rio de Janeiro (Brazil): Radiological characterization and relationships to geological formation, soil types and soil properties.
[So] Source:J Environ Radioact;182:34-43, 2018 Feb.
[Is] ISSN:1879-1700
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Located in the south-western part of Brazil, the state of Rio de Janeiro is geotectonically contained within a complex structural province that resulted in the amalgamation of the Western Gondwana Paleocontinent. To undertake an extensive radiological characterization of this complex geological province and investigate the influence of bedrock, soil type and soil chemical-physical characteristics on natural radionuclide levels in soils, 259 surface soil samples were collected that encompassed the main soil types and geological formations throughout the state. Gamma spectrometry analysis of the samples resulted in median values of 114 Bq.kg for K, 32 Bq.kg for Ra and 74 Bq.kg for Ra. The median value for Ra was similar to the world median value for soils, the K value was well below the worldwide value, and that for Ra exceeded the world median value. The intense weathering caused by the high rainfall rates and high temperatures may be responsible for the low levels of K in the soils, of which the strongly acidic and clayey soils are markedly K-depleted. A soil from a high-grade metamorphic rock (granulite) presented the lowest Ra (18 Bq.kg ) content, whereas the highest levels for Ra (92 Bq.kg ) and Ra (139 Bq.kg 1) were observed in a young soil enriched in primary minerals (Leptsol). A lowland soil (Gleysol) showed the highest median of K (301 Bq.kg ). Strongly acidic soils tended to present high amounts of Ra, and sandy soils tended to contain low levels of Ra. The external radiation dose indicates that the state has a background radiation level within the natural range.
[Mh] Termos MeSH primário: Monitoramento de Radiação
Poluentes Radioativos do Solo/análise
Solo/química
[Mh] Termos MeSH secundário: Radiação de Fundo
Brasil
Radioisótopos de Potássio/análise
Radioatividade
Rádio (Elemento)/análise
Tório/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Potassium Radioisotopes); 0 (Soil); 0 (Soil Pollutants, Radioactive); 60YU5MIG9W (Thorium); W90AYD6R3Q (Radium)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171228
[Lr] Data última revisão:
171228
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171129
[St] Status:MEDLINE


  6 / 1608 MEDLINE  
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[PMID]:28854194
[Au] Autor:Stinnesbeck W; Becker J; Hering F; Frey E; González AG; Fohlmeister J; Stinnesbeck S; Frank N; Terrazas Mata A; Benavente ME; Avilés Olguín J; Aceves Núñez E; Zell P; Deininger M
[Ad] Endereço:Institut für Geowissenschaften, Universität Heidelberg, Im Neuenheimer Feld 234, Heidelberg, Germany.
[Ti] Título:The earliest settlers of Mesoamerica date back to the late Pleistocene.
[So] Source:PLoS One;12(8):e0183345, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Preceramic human skeletal remains preserved in submerged caves near Tulum in the Mexican state of Quintana Roo, Mexico, reveal conflicting results regarding 14C dating. Here we use U-series techniques for dating a stalagmite overgrowing the pelvis of a human skeleton discovered in the submerged Chan Hol cave. The oldest closed system U/Th age comes from around 21 mm above the pelvis defining the terminus ante quem for the pelvis to 11311±370 y BP. However, the skeleton might be considerable older, probably as old as 13 ky BP as indicated by the speleothem stable isotope data. The Chan Hol individual confirms a late Pleistocene settling of Mesoamerica and represents one of the oldest human osteological remains in America.
[Mh] Termos MeSH primário: Cavernas
Fósseis
Paleontologia/métodos
Datação Radiométrica/métodos
[Mh] Termos MeSH secundário: Radioisótopos de Carbono/metabolismo
Seres Humanos
México
Pelve/anatomia & histologia
Esqueleto/anatomia & histologia
Tório/metabolismo
Fatores de Tempo
Urânio/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Carbon Radioisotopes); 4OC371KSTK (Uranium); 60YU5MIG9W (Thorium)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171023
[Lr] Data última revisão:
171023
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170831
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0183345


  7 / 1608 MEDLINE  
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[PMID]:28511933
[Au] Autor:Lv K; Yang CT; Han J; Hu S; Wang XL
[Ad] Endereço:Radiochemistry Lab, Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, China.
[Ti] Título:An initial demonstration of hierarchically porous niobium alkylphosphonates coordination polymers as potent radioanalytical separation materials.
[So] Source:J Chromatogr A;1504:35-45, 2017 Jun 30.
[Is] ISSN:1873-3778
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Combining the merits of soft-templating and perchlorate oxidation methods, the first-case investigation of niobium alkylphosphonates has uncovered their unique morphology, backbone composition, thermal behavior and huge potentiality as radioanalytical separation materials. These hierarchically porous solids are random aggregates of densely stacked nanolayers perforated with worm-like holes or vesicular voids, manifesting the massif-, tower-like "polymer brush" elevated up to ∼150nm driven by the minimal surface free energy principle. These coordination polymers consist of distorted niobium (V) ions strongly linked with tetrahedral alkylphosphonate building units, exposing uncoordinated phosphonate moieties and defective metal sites. Despite the amorphous features, they demonstrate multimodal porosity covering continuous micropores, segregated mesopores and fractional macropores, beneficial for the sequestration by active Lewis acid-base center. Evidenced by the maximum distribution coefficients of thorium, lanthanides reaching 9.0×10 , 9.5×10 mLg and large separation factor at pH≤1 20-element cocktail, this category of niobium alkylphosphonates are capable of harvesting thorium, lanthanides directly from the radionuclide surrogate, comparable to or even surpass the performance of the metal (IV) arylphosphonates counterparts. They also display appreciable SF ∼20 in 1molL HNO , shedding light on dual approaches to achieve the isolation of americium from curium. A combinatorial radioanalytical separation protocol has been proposed to enrich thorium and europium, revealing facile utilization of these highly stable, phosphonated hybrids in sustainable development of radioanalytical separation.
[Mh] Termos MeSH primário: Nióbio/química
Polímeros/química
Tório/isolamento & purificação
[Mh] Termos MeSH secundário: Elementos da Série dos Lantanídeos/química
Elementos da Série dos Lantanídeos/isolamento & purificação
Ácidos de Lewis/química
Organofosfonatos/química
Porosidade
Tório/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Lanthanoid Series Elements); 0 (Lewis Acids); 0 (Organophosphonates); 0 (Polymers); 05175J654G (Niobium); 60YU5MIG9W (Thorium)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171103
[Lr] Data última revisão:
171103
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170518
[St] Status:MEDLINE


  8 / 1608 MEDLINE  
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[PMID]:28411426
[Au] Autor:Sudeep Kumara K; Sahoo BK; Gaware JJ; Sapra BK; Mayya YS; Karunakara N
[Ad] Endereço:Centre for Advanced Research in Environmental Radioactivity, Mangalore University, Mangalagangothri, 574199, Mangalore, India.
[Ti] Título:Thoron Mitigation System based on charcoal bed for applications in thorium fuel cycle facilities (part 2): Development, characterization, and performance evaluation.
[So] Source:J Environ Radioact;172:249-260, 2017 Jun.
[Is] ISSN:1879-1700
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Exposure due to thoron ( Rn) gas and its decay products in a thorium fuel cycle facility handling thorium or U/ U mixture compounds is an important issue of radiological concern requiring control and mitigation. Adsorption in a flow-through charcoal bed offers an excellent method of alleviating the release of Rn into occupational and public domain. In this paper, we present the design, development, and characterization of a Thoron Mitigation System (TMS) for industrial application. Systematic experiments were conducted in the TMS for examining the Rn mitigation characteristics with respect to a host of parameters such as flow rate, pressure drop, charcoal grain size, charcoal mass and bed depth, water content, and heat of the carrier gas. An analysis of the experimental data shows that Rn attenuation in a flow through charcoal bed is not exponential with respect to the residence time, L/U (L: bed depth; U : superficial velocity), but follows a power law behaviour, which can be attributed to the occurrence of large voids due to wall channeling in a flow through bed. The study demonstrates the regeneration of charcoal adsorption capacity degraded due to moisture adsorption, by hot air blowing technique. It is found that the mitigation factor (MF), which is the ratio of the inlet Rn concentration (C ) to the outlet Rn concentration (C ), of more than 10 for the TMS is easily achievable during continuous operation (>1000 h) at a flow rate of 40 L min with negligible (<1 cm of water column) pressure drop. The Thoron Mitigation System based on adsorption on charcoal bed offers a compact and effective device to remove Rn from affluent air streams in a space constrained domain. The prototype system has been installed in a thorium fuel cycle facility where it is being evaluated for its long-term performance and overall effectiveness in mitigating Rn levels in the workplace.
[Mh] Termos MeSH primário: Poluição do Ar em Ambientes Fechados/prevenção & controle
Recuperação e Remediação Ambiental/métodos
Tório/análise
[Mh] Termos MeSH secundário: Adsorção
Poluentes Radioativos do Ar/análise
Carvão Vegetal
Centrais Nucleares
Radônio/análise
Urânio/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Air Pollutants, Radioactive); 16291-96-6 (Charcoal); 4OC371KSTK (Uranium); 60YU5MIG9W (Thorium); Q74S4N8N1G (Radon)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170602
[Lr] Data última revisão:
170602
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170416
[St] Status:MEDLINE


  9 / 1608 MEDLINE  
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[PMID]:28411425
[Au] Autor:Sahoo BK; Sudeep Kumara K; Karunakara N; Gaware JJ; Sapra BK; Mayya YS
[Ad] Endereço:Radiological Physics & Advisory Division, Bhabha Atomic Research Centre, Mumbai 400 085, India.
[Ti] Título:Thoron Mitigation System based on charcoal bed for applications in thorium fuel cycle facilities (part 1): Development of theoretical models for design considerations.
[So] Source:J Environ Radioact;172:237-248, 2017 Jun.
[Is] ISSN:1879-1700
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Regulating the environmental discharge of Rn (historically known as thoron) and its decay products from thorium processing facilities is important for protection of environment and general public living in the vicinities. Activated charcoal provides an effective solution to this problem because of its high adsorption capacity to gaseous element like radon. In order to design and develop a charcoal based Thoron Mitigation System, a mathematical model has been developed in the present work for studying the Rn transport and adsorption in a flow through charcoal bed and estimating the Rn mitigation factor (MF) as a function of system and operating parameters. The model accounts for inter- and intra-grain diffusion, advection, radioactive decay and adsorption processes. Also, the effects of large void fluctuation and wall channeling on the mitigation factor have been included through a statistical model. Closed form solution has been provided for the MF in terms of adsorption coefficient, system dimensions, grain size, flow rate and void fluctuation exponent. It is shown that the delay effects due to intra grain diffusion plays a significant role thereby rendering external equilibrium assumptions unsuitable. Also, the application of the statistical model clearly demonstrates the transition from the exponential MF to a power-law form and shows how the occurrence of channels with low probability can lower mitigation factor by several orders of magnitude. As a part of aiding design, the model is further extended to optimise the bed dimensions in respect of pressure drop and MF. The application of the results for the design and development of a practically useful charcoal bed is discussed.
[Mh] Termos MeSH primário: Poluentes Radioativos do Ar/análise
Poluição do Ar em Ambientes Fechados/análise
Monitoramento de Radiação
Tório/análise
[Mh] Termos MeSH secundário: Adsorção
Poluição do Ar em Ambientes Fechados/estatística & dados numéricos
Carvão Vegetal
Difusão
Modelos Estatísticos
Modelos Teóricos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Air Pollutants, Radioactive); 16291-96-6 (Charcoal); 60YU5MIG9W (Thorium)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170602
[Lr] Data última revisão:
170602
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170416
[St] Status:MEDLINE


  10 / 1608 MEDLINE  
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[PMID]:28402142
[Au] Autor:Frenvik JO; Dyrstad K; Kristensen S; Ryan OB
[Ad] Endereço:a Bayer AS , Lysaker, Oslo , Norway.
[Ti] Título:Development of separation technology for the removal of radium-223 from targeted thorium conjugate formulations. Part II: purification of targeted thorium conjugates on cation exchange columns.
[So] Source:Drug Dev Ind Pharm;43(9):1440-1449, 2017 Sep.
[Is] ISSN:1520-5762
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Tumor targeting pharmaceuticals will play a crucial role in future pharma pipelines. The targeted thorium conjugate (TTC) therapeutic platform could provide real benefit to patients, whereby targeting moieties like monoclonal antibodies are radiolabelled with the alpha-emitting radionuclide thorium-227 ( Th, t = 18.7 days). A potential problem could be the accumulation of the long-lived daughter nuclide radium-223 ( Ra, t = 11.4 days) in the drug product during manufacturing and distribution. Therefore, the level of Ra must be standardized before administration to the patient. The focus in this study has been the removal of Ra, as the other progenies will have a very limited stay in the formulation. In this study, the purification of TTCs labeled with decayed Th has been explored. Columns packed with a strong cation exchange resin have been used to sequester Ra. The separation of TTC from Ra has been evaluated as influenced by both formulation and process parameters with a design of experiments (DOE) study; including citrate or acetate buffer, pH, buffer concentration, presence or absence of pABA + EDTA, resin amount and sodium chloride concentration. The aim was to achieve a separation with high sorption of Ra and accompanying low TTC sorption. The results were analyzed by multivariate analysis. Four regression models of TTC and Ra sorption from citrate and acetate buffered formulations were developed. The predictive accuracy of sorption in the four statistical models was given by standard deviations and confidence intervals. The TTC sorption in citrate and acetate buffered formulations was affected by the identical variables and the variation in TTC sorption was comparable for the two models. However, the DOE variables had a significantly stronger impact on the Ra sorption in citrate buffered formulations than the Ra sorption in acetate buffer. An optimal separation with a TTC sorption below 25% and Ra sorption above 90% can be achieved in both citrate and acetate buffered formulations. Stability studies of radiochemical purity (RCP) indicated that the measured Th values may be partly due to free Th and not TTC, but the results indicate that TTC stability may be controlled by optimizing formulation parameters. Hence, the sorption data and the regression models presented must be reviewed and further explored with regard to what is known about the stability of the TTC in the different buffered formulations.
[Mh] Termos MeSH primário: Anticorpos Monoclonais/química
Cátions/química
Rádio (Elemento)/química
[Mh] Termos MeSH secundário: Anticorpos Monoclonais/metabolismo
Tampões (Química)
Química Farmacêutica
Compostos Radiofarmacêuticos
Tório/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Monoclonal); 0 (Buffers); 0 (Cations); 0 (Radiopharmaceuticals); 60YU5MIG9W (Thorium); W90AYD6R3Q (Radium)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170928
[Lr] Data última revisão:
170928
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170413
[St] Status:MEDLINE
[do] DOI:10.1080/03639045.2017.1318906



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