scholarly journals Efficient Production of High Specific Activity Thulium-167 at Paul Scherrer Institute and CERN-MEDICIS

2021 ◽  
Vol 8 ◽  
Author(s):  
Reinhard Heinke ◽  
Eric Chevallay ◽  
Katerina Chrysalidis ◽  
Thomas E. Cocolios ◽  
Charlotte Duchemin ◽  
...  
Keyword(s):  
Ion Beam ◽  
High Specific Activity ◽  
Mass Separation ◽  
Paul Scherrer Institute ◽  
Process Efficiency ◽  
Resonance Ionization ◽  
Gamma Line ◽  
Limiting Factor ◽  
Efficient Production ◽  
Paul Scherrer

Thulium-167 is a promising radionuclide for nuclear medicine applications with potential use for both diagnosis and therapy (“theragnostics”) in disseminated tumor cells and small metastases, due to suitable gamma-line as well as conversion/Auger electron energies. However, adequate delivery methods are yet to be developed and accompanying radiobiological effects to be investigated, demanding the availability of 167Tm in appropriate activities and quality. We report herein on the production of radionuclidically pure 167Tm from proton-irradiated natural erbium oxide targets at a cyclotron and subsequent ion beam mass separation at the CERN-MEDICIS facility, with a particular focus on the process efficiency. Development of the mass separation process with studies on stable 169Tm yielded 65 and 60% for pure and erbium-excess samples. An enhancement factor of thulium ion beam over that of erbium of up to several 104 was shown by utilizing laser resonance ionization and exploiting differences in their vapor pressures. Three 167Tm samples produced at the IP2 irradiation station, receiving 22.8 MeV protons from Injector II at Paul Scherrer Institute (PSI), were mass separated with collected radionuclide efficiencies between 11 and 20%. Ion beam sputtering from the collection foils was identified as a limiting factor. In-situ gamma-measurements showed that up to 45% separation efficiency could be fully collected if these limits are overcome. Comparative analyses show possible neighboring mass suppression factors of more than 1,000, and overall 167Tm/Er purity increase in the same range. Both the actual achieved collection and separation efficiencies present the highest values for the mass separation of external radionuclide sources at MEDICIS to date.

scholarly journals Terbium Medical Radioisotope Production: Laser Resonance Ionization Scheme Development

2021 ◽  
Vol 8 ◽  
Author(s):  
Vadim Maratovich Gadelshin ◽  
Roberto Formento Cavaier ◽  
Ferid Haddad ◽  
Reinhard Heinke ◽  
Thierry Stora ◽  
...  
Keyword(s):  
Ion Beam ◽  
Target Material ◽  
Atomic Ratio ◽  
Mass Separation ◽  
Resonance Excitation ◽  
Resonance Ionization ◽  
Laser Resonance ◽  
High Ionization ◽  
Medical Radioisotope ◽  
Ionization Scheme

Terbium (Tb) is a promising element for the theranostic approach in nuclear medicine. The new CERN-MEDICIS facility aims for production of its medical radioisotopes to support related R&D projects in biomedicine. The use of laser resonance ionization is essential to provide radioisotopic yields of highest quantity and quality, specifically regarding purity. This paper presents the results of preparation and characterization of a suitable two-step laser resonance ionization process for Tb. By resonance excitation via an auto-ionizing level, the high ionization efficiency of 53% was achieved. To simulate realistic production conditions for Tb radioisotopes, the influence of a surplus of Gd atoms, which is a typical target material for Tb generation, was considered, showing the necessity of radiochemical purification procedures before mass separation. Nevertheless, a 10-fold enhancement of the Tb ion beam using laser resonance ionization was observed even with Gd:Tb atomic ratio of 100:1.

scholarly journals CERN-MEDICIS: A Review Since Commissioning in 2017

2021 ◽  
Vol 8 ◽  
Author(s):  
Charlotte Duchemin ◽  
Joao P. Ramos ◽  
Thierry Stora ◽  
Essraa Ahmed ◽  
Elodie Aubert ◽  
...  
Keyword(s):  
Separation Efficiency ◽  
Specific Activity ◽  
Ion Beam ◽  
High Specific Activity ◽  
Ion Source ◽  
Mass Separation ◽  
Special Focus ◽  
Proton Synchrotron ◽  
Laser Ion Source ◽  
Isotope Separator

The CERN-MEDICIS (MEDical Isotopes Collected from ISolde) facility has delivered its first radioactive ion beam at CERN (Switzerland) in December 2017 to support the research and development in nuclear medicine using non-conventional radionuclides. Since then, fourteen institutes, including CERN, have joined the collaboration to drive the scientific program of this unique installation and evaluate the needs of the community to improve the research in imaging, diagnostics, radiation therapy and personalized medicine. The facility has been built as an extension of the ISOLDE (Isotope Separator On Line DEvice) facility at CERN. Handling of open radioisotope sources is made possible thanks to its Radiological Controlled Area and laboratory. Targets are being irradiated by the 1.4 GeV proton beam delivered by the CERN Proton Synchrotron Booster (PSB) on a station placed between the High Resolution Separator (HRS) ISOLDE target station and its beam dump. Irradiated target materials are also received from external institutes to undergo mass separation at CERN-MEDICIS. All targets are handled via a remote handling system and exploited on a dedicated isotope separator beamline. To allow for the release and collection of a specific radionuclide of medical interest, each target is heated to temperatures of up to 2,300°C. The created ions are extracted and accelerated to an energy up to 60 kV, and the beam steered through an off-line sector field magnet mass separator. This is followed by the extraction of the radionuclide of interest through mass separation and its subsequent implantation into a collection foil. In addition, the MELISSA (MEDICIS Laser Ion Source Setup At CERN) laser laboratory, in service since April 2019, helps to increase the separation efficiency and the selectivity. After collection, the implanted radionuclides are dispatched to the biomedical research centers, participating in the CERN-MEDICIS collaboration, for Research & Development in imaging or treatment. Since its commissioning, the CERN-MEDICIS facility has provided its partner institutes with non-conventional medical radionuclides such as Tb-149, Tb-152, Tb-155, Sm-153, Tm-165, Tm-167, Er-169, Yb-175, and Ac-225 with a high specific activity. This article provides a review of the achievements and milestones of CERN-MEDICIS since it has produced its first radioactive isotope in December 2017, with a special focus on its most recent operation in 2020.

scholarly journals Emittance measurements of the ACCEL K250 superconducting medical cyclotron at Paul Scherer institute

2006 ◽  
Vol 21 (1) ◽  
pp. 58-60
Author(s):  
Dragan Toprek
Keyword(s):  
Proton Beam ◽  
Beam Profile ◽  
Paul Scherrer Institute ◽  
Superconducting Cyclotron ◽  
Paul Scherrer ◽  
Quadrupole Method

The results of beam profile measurements of the proton beam of the ACCEL K250 superconducting cyclotron at the Paul Scherrer Institute are presented in this paper. Beam emittances in both horizontal and vertical planes are estimated by the varying quadrupole method.

scholarly journals Production of Sm-153 With Very High Specific Activity for Targeted Radionuclide Therapy

2021 ◽  
Vol 8 ◽  
Author(s):  
Michiel Van de Voorde ◽  
Charlotte Duchemin ◽  
Reinhard Heinke ◽  
Laura Lambert ◽  
Eric Chevallay ◽  
...  
Keyword(s):  
Neutron Irradiation ◽  
Radionuclide Therapy ◽  
High Efficiency ◽  
Separation Efficiency ◽  
Specific Activity ◽  
High Specific Activity ◽  
Mass Separation ◽  
Full Potential ◽  
Targeted Radionuclide Therapy ◽  
Very High

Samarium-153 (153Sm) is a highly interesting radionuclide within the field of targeted radionuclide therapy because of its favorable decay characteristics. 153Sm has a half-life of 1.93 d and decays into a stable daughter nuclide (153Eu) whereupon β− particles [E = 705 keV (30%), 635 keV (50%)] are emitted which are suitable for therapy. 153Sm also emits γ photons [103 keV (28%)] allowing for SPECT imaging, which is of value in theranostics. However, the full potential of 153Sm in nuclear medicine is currently not being exploited because of the radionuclide's limited specific activity due to its carrier added production route. In this work a new production method was developed to produce 153Sm with higher specific activity, allowing for its potential use in targeted radionuclide therapy. 153Sm was efficiently produced via neutron irradiation of a highly enriched 152Sm target (98.7% enriched, σth = 206 b) in the BR2 reactor at SCK CEN. Irradiated target materials were shipped to CERN-MEDICIS, where 153Sm was isolated from the 152Sm target via mass separation (MS) in combination with laser resonance enhanced ionization to drastically increase the specific activity. The specific activity obtained was 1.87 TBq/mg (≈ 265 times higher after the end of irradiation in BR2 + cooling). An overall mass separation efficiency of 4.5% was reached on average for all mass separations. Further radiochemical purification steps were developed at SCK CEN to recover the 153Sm from the MS target to yield a solution ready for radiolabeling. Each step of the radiochemical process was fully analyzed and characterized for further optimization resulting in a high efficiency (overall recovery: 84%). The obtained high specific activity (HSA) 153Sm was then used in radiolabeling experiments with different concentrations of 4-isothiocyanatobenzyl-1,4,7,10-tetraazacyclododecane tetraacetic acid (p-SCN-Bn-DOTA). Even at low concentrations of p-SCN-Bn-DOTA, radiolabeling of 0.5 MBq of HSA 153Sm was found to be efficient. In this proof-of-concept study, we demonstrated the potential to combine neutron irradiation with mass separation to supply high specific activity 153Sm. Using this process, 153SmCl3 suitable for radiolabeling, was produced with a very high specific activity allowing application of 153Sm in targeted radionuclide therapy. Further studies to incorporate 153Sm in radiopharmaceuticals for targeted radionuclide therapy are ongoing.

Advanced Cooling Tower Concept for Commercial and Industrial Applications

2014 ◽  
Author(s):  
Sergey Anisimov ◽  
Aleksandr Kozlov ◽  
Paul Glanville ◽  
Mark Khinkis ◽  
Valeriy Maisotsenko ◽  
...  
Keyword(s):  
Cooling Tower ◽  
Industrial Applications ◽  
Process Efficiency ◽  
Limiting Factor ◽  
Cooling Towers ◽  
Water Stream ◽  
Cooling Performance ◽  
Evaporative Cooler ◽  
Direct Evaporative Cooler ◽  
The U.S

For the majority of cooling towers installed, of which there are greater than half a million installed in the U.S., tower design uses direct evaporative cooler technology where an ideally enthalpy-neutral process cools the process water stream to a temperature above the ambient wet bulb. This ambient wet bulb temperature is the limiting factor for the process cooling. As such the energy-water connection is clear, these cooling towers are direct consumers of treated water and their cooling performance is intimately tied to the process efficiency.

Multi-Ion Beam Lithography and Processing Studies

2011 ◽  
Vol 1354 ◽  
Author(s):  
Bill R. Appleton ◽  
Sefaattin Tongay ◽  
Maxime Lemaitre ◽  
Brent Gila ◽  
David Hays ◽  
...  
Keyword(s):  
Ion Beam ◽  
Mass Separation ◽  
Morphological Transformation ◽  
University Of Florida ◽  
Temporal Precision ◽  
Ion Beam Lithography ◽  
Si Nanocrystals ◽  
Wide Range ◽  
Liquid Metal Alloy ◽  
The University

ABSTRACTThe University of Florida (UF) have recently collaborated with Raith Inc. to modify Raith’s ion beam lithography, nanofabrication and engineering (ionLiNE) station that utilizes only Ga ions, into a multi-ion beam system (MionLiNE) by adding the capabilities to use liquid metal alloy sources (LMAIS) to access a variety of ions and an EXB filter for mass separation. The MionLiNE modifications discussed below provide a wide range of spatial and temporal precision that can be used to investigate ion solid interactions under extended boundary conditions, as well as for ion lithography and nanofabrication. Here we demonstrate the ion beam lithographic capabilities of the MionLiNE for fabricating patterned arrays of Au and Si nanocrystals, with nanoscale dimensions, in SiO2 substrates, by direct implantation; and show that the same directwrite/maskless-implantation features can be used for in situ fabrication of nanoelectronic devices. Additionally, the spatial and temporal capabilities of the MionLiNE are used to explore the effects of dose rate on the long-standing surface morphological transformation that occurs in ion bombarded Ge.

scholarly journals Production, isolation and characterization of radiochemically pure 163Ho samples for the ECHo-project

2018 ◽  
Vol 106 (7) ◽  
pp. 535-547 ◽  
Author(s):  
Holger Dorrer ◽  
Katerina Chrysalidis ◽  
Thomas Day Goodacre ◽  
Christoph E. Düllmann ◽  
Klaus Eberhardt ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Energy Spectrum ◽  
Neutron Activation ◽  
Thermal Neutron ◽  
Electron Capture ◽  
Mass Separation ◽  
Thermal Neutron Activation ◽  
Resonance Ionization ◽  
Resonance Ionization Mass Spectrometry ◽  
Isolation And Characterization

Abstract Several experiments on the study of the electron neutrino mass are based on high-statistics measurements of the energy spectrum following electron capture of the radionuclide 163Ho. They rely on the availability of large, radiochemically pure samples of 163Ho. Here, we describe the production, separation, characterization, and sample production within the Electron Capture in Holmium-163 (ECHo) project. 163Ho has been produced by thermal neutron activation of enriched, prepurified 162Er targets in the high flux reactor of the Institut Laue-Langevin, Grenoble, France, in irradiations lasting up to 54 days. Irradiated targets were chemically processed by means of extraction chromatography, which allowed separating the formed Ho from the 162Er target-material and from the main byproducts 170Tm and 171Tm, which are co-produced in GBq amounts. Decontamination factors of >500 for Er and of >105 for Tm and yields of 3.6·1016 and 1.2·1018 atoms of 163Ho were obtained, corresponding to a recovery yield of 95 % of Ho in the chemical separation. The Ho-fraction was characterized by means of γ-ray spectrometry, Inductively-Coupled-Plasma Mass Spectrometry (ICP-MS), Resonance Ionization Mass Spectrometry (RIMS) and Neutron Activation Analysis (NAA). In this process, the thermal neutron capture cross section of 163Ho was measured to σHo-163 to Ho-164m= (23±3) b and σHo-163 to Ho-164g= (156±9) b for the formation of the two isomers of 164Ho. Specific samples were produced for further purification by mass separation to isolate 163Ho from the Ho-isotope mixture, as needed for obtaining the energy spectrum within ECHo. The partial efficiency for this second separation step is (32±5) %.

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