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[en] The overview of this presentation is: (1) Introduction to nonproliferation efforts; (2) Scope of activities Los Alamos National Laboratory; (3) Facilities for radioanalytical work at LANL; (4) Radiochemical characterization capabilities; and (5) Bulk chemical and materials analysis capabilities.
[en] Over recent years, within the community of radiopharmaceutical sciences, there has been an increased incidence of incorrect usage of established scientific terms and conventions, and even the emergence of ‘self-invented’ terms. Here, in order to address these concerns, an international Working Group on ‘Nomenclature in Radiopharmaceutical Chemistry and related areas’ was established in 2015 to achieve clarification of terms and to generate consensus on the utilisation of a standardised nomenclature pertinent to the field. Upon open consultation, the following consensus guidelines were agreed, which aim to: Provide a reference source for nomenclature good practice in the radiopharma-ceutical sciences; Clarify the use of terms and rules concerning exclusively radiopharmaceutical terminology, i.e. nuclear- and radiochemical terms, symbols and expressions; Address gaps and inconsistencies in existing radiochemistry nomenclature rules; Provide source literature for further harmonisation beyond our immediate peer group (publishers, editors, IUPAC, pharmacopoeias, etc.).
[en] Full text : Registration of the fluctuations of the solar radio emission is one of the ways to study the wave and turbulent processes occurring on the Sun. It is known that the radio spectrographic measurements of the radio emission of the Sun provide a wealth of information on the physical conditions in the vast regions of the Sun, from the chromosphere to the super-corona. In his paper we give a brief overview of radio spectrographic measurements of the quiet and active solar radio emission. In particular, at the Institute of Radio Physics in Russia, Professor M.M. Kobrin found the fine structure of the S-component the solar radio emission in the range of 4 - 12 GHz. It has been speculated that the fine structure can exist in the longer wavelength part of the centimeter range, and in the short-wave range. To test this hypothesis it was constructed the radio spectrographs based on the domestic receivers in the range of 1-2 GHz and 2-4 GHz and conducted extensive observations with RT-7.5, RT-12 Ionosphere Institute, Academy of Sciences of the Republic of Kazakhstan and RT-22. It is known that the shape of the spectrum allows to judge about the role of a mechanism responsible for the radio emission of the Sun. Study of the structure of the frequency spectrum of S-component of the Sun and its changes provide information about the relatively slow processes in the local sources at formation there the conditions for the emergence of powerful flares. Analysis of data derived from the slopes of the spectra in the moments preceding these events, allowed to make the following conclusions: 1. short-modulation spectral slope of S-component of the solar radio emission with changes about 7 x t and 15 minutes has a small amplitude and spectrum of the fine structure been weakened; 2. for 1-3 days prior to the powerful flash the slope of the S-component of solar radio emission with a change of temperature within 20 - 35 minutes have a higher amplitude in the spectra and the fine structure is well reflected. Thus, summarizing the above analysis it was drawn the conclusion that the change in the amplitude of slope of the spectrum of S-component of solar radio emission in the range of 1-4 GHz is one of the best options preceding the powerful solar flares in 1-3 days prior to the event
[en] Summary: The CGS 25966 derivative (R)-2-(N-Benzyl-4-(2-[18F]fluoroethoxy)phenyl-sulphonamido) -N-hydroxy-3-methylbutanamide [18F]9 represents a very potent radiolabelled matrix metalloproteinase inhibitor. For first human PET studies it is mandatory to have a fully automated radiosynthesis and a straightforward precursor synthesis available. The realisation of both requirements is reported herein. In particular, the corresponding precursor 8 was obtained in a reliable 7 step synthesis with an overall chemical yield of 2.3%. Furthermore, the target compound [18F]9 was prepared with a radiochemical yield of 14.8±3.9% (not corrected for decay).
[en] Highlights: • A radio-analytical method was validated for the [11C]GSK1482160 radiopharmaceutical. • The method proved to be robust and unaffected by small changes in the chromatographic conditions. • The [11C]GSK1482160 radiopharmaceutical exhibits high radiochemical stability. • [11C]GSK1482160 radiopharmaceutical can be delivered in accordance with USP requirements. • The P2X7-receptor-targeted [11C]GSK1482160 meets release criteria for human use. - Abstract: A radio-analytical RP-HPLC method was developed and validated to support production of the P2X7-receptor-targeted [11C]GSK1482160 radiopharmaceutical. Method validation included characterization of retention times, peak shapes, linearity, accuracy, precision, selectivity, limits of detection and quantitation (UV signal), radiochemical stability, as well as analytical method range and robustness. The validated radio-HPLC method is suitable for the definition of [11C]GSK1482160 radiochemical identity, radiochemical purity, as well as molar activity, and is being employed in support of human studies with [11C]GSK1482160.
[en] The motivation, history and status of coordination of education and training in nuclear- and radiochemistry in Europe are reviewed. The achievements of the Euratom FP7 project 'Cooperation In education in Nuclear CHemistry (CINCH)' are described. Attention is paid to the results of the survey of universities teaching nuclear chemistry and their respective curricula evaluation, to the plan to introduce the EuroMaster in nuclear- and radiochemistry quality label recognized and guaranteed by the European Association for Chemical and Molecular Sciences (EuCheMS), and to CINCH NucWik - an interactive database proposed and implemented as an open structure in the form of a 'Wiki'. (author)
[en] Tumors such as prostate, small cell lung cancer, breast, gastric and colon cancer are known to overexpress receptors to bombesin (BBN). In this study, a new bombesin analogue was labeled with 99mTc via HYNIC and tricine/EDDA as coligands and investigated further. HYNIC-GABA-Bombesin (7-14) NH2 was synthesized using a standard Fmoc strategy. Labeling with 99mTc was performed at 100 deg C for 10 min and radiochemical analysis involved ITLC and HPLC methods. The stability of radiopeptide was checked in the presence of humane serum at 37 deg C up to 24 h. The receptor bound internalization and externalization rates were studied in GRP receptor expressing PC-3 cells. Biodistribution of radiopeptide was studied in nude mice bearing PC-3 tumor. Labeling yield of >98% was obtained corresponding to a specific activity of ∼2.6 MBq/nmol. Peptide conjugate showed good stability in the presence of human serum. The radioligand showed high and specific internalization into PC-3 cells (14.63 ± 0.41% at 4 h). In biodistribution studies, a receptor-specific uptake was observed in GRP-receptor-positive organs so that after 4 h the uptakes in mouse tumor and pancreas were 1.31 ± 0.18 and 1.2 ± 0.13% ID/g, respectively. (author)
[en] — Counting characteristics of the system for recording rare events of the 71Ge decay in the radiochemical gallium Baksan Experiment on Sterile Transitions (BEST) are presented. Events are recorded simultaneously along eight counting channels in the energy range 0.3–16 keV, which include 71Ge decays in the region of L and K peaks with a total efficiency of up to 75%. The data analysis is based on the recording of the full shape of the leading edge of the charge pulses using a digital oscilloscope.