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https://www.readbyqxmd.com/read/28447672/from-11-c-co2-to-11-c-amides-a-rapid-one-pot-synthesis-via-the-mitsunobu-reaction
#1
S Bongarzone, A Runser, C Taddei, A K Haji Dheere, A D Gee
A novel amide synthesis methodology is described using amines, CO2 and Grignard reagents and Mitsunobu reagents. The method was applied to carbon-11 radiochemistry to label amides using cyclotron-produced [(11)C]CO2. The synthetic utility of the one-pot labelling methodology was demonstrated by producing [(11)C]melatonin. The incorporation of [(11)C]CO2 into [(11)C]melatonin was 36% - determined by radioHPLC 2 min post [(11)C]CO2 delivery.
April 27, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28443689/recent-achievements-in-tc-99m-radiopharmaceutical-direct-production-by-medical-cyclotrons
#2
Alessandra Boschi, Petra Martini, Micol Pasquali, Licia Uccelli
(99m)Tc is the most commonly used radionuclide in the field of diagnostic imaging, a noninvasive method intended to diagnose a disease, assess the disease state and monitor the effects of treatments. Annually, the use of (99m)Tc, covers about 85% of nuclear medicine applications. This isotope releases gamma rays at about the same wavelength as conventional X-ray diagnostic equipment, and owing to its short half-life (t½ = 6 hours) is ideal for diagnostic nuclear imaging. A patient can be injected with a small amount of (99m)Tc and within 24 hours almost 94% of the injected radionuclide would have decayed and left the body, limiting the patient's radiation exposure...
April 26, 2017: Drug Development and Industrial Pharmacy
https://www.readbyqxmd.com/read/28440636/probing-and-comparing-the-photobromination-and-photoiodination-of-dissolved-organic-matter-by-using-ultrahigh-resolution-mass-spectrometry
#3
Zhineng Hao, Yongguang Yin, Dong Cao, Jing-Fu Liu
Photochemical halogenation of dissolved organic matter (DOM) may represent an important abiotic source of natural organobromine compounds (OBCs) and natural organoiodine compounds (OICs) within surface waters. Here we report the significantly enhanced formation of OBCs and OICs by photohalogenating DOM in freshwater and seawater, as well as the noticeable difference in distribution and composition pattern of newly formed OBCs and OICs. By using the negative ion electrospray ionization coupled with Fourier transform ion cyclotron resonance mass spectrometry, numerous OBCs and OICs were identified during the photo halogenation processes in sunlit waters...
April 25, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28437719/matrix-assisted-laser-desorption-ionization-mass-spectrometric-imaging-of-olanzapine-in-a-single-hair-using-esculetin-as-a-matrix
#4
Hang Wang, Ying Wang, Ge Wang, Lizhi Hong
Matrix-assisted laser desorption/ionization-mass spectrometric imaging (MALDI-MSI) for the analysis of intact hair is a powerful tool for monitoring changes in drug consumption. The embedding of a low drug concentration in the hydrophobic hair matrix makes it difficult to extract and detect, and requires an improved method to increase detection sensitivity. In this study, an MSI method using MALDI-Fourier transform ion cyclotron resonance was developed for direct identification and imaging of olanzapine in hair samples using the positive ion mode...
April 18, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28436222/influence-of-nitric-acid-on-the-helium-ion-radiolysis-of-aqueous-butanal-oxime-solutions
#5
Amaury Costagliola, Laurent Venault, Arnaud Deroche, Jackie Vermeulen, Florian Duval, Guillaume Blain, Johan Vandenborre, Massoud Fattahi-Vanani, Nicolas Vigier
Samples of butanal oxime in aqueous nitric acid solutions have been irradiated with the helium ion (4He2+) beam of the CEMHTI (Orléans, France) cyclotrons. The consumption yield of butanal oxime has been measured by gas-chromatography coupled with mass spectrometry. Gaseous products (mainly H2 and N2O) have also been monitored by micro gas-chromatography. Yields of liquid phase products (hydrogen peroxide and nitrous acid) have been determined by colorimetric methods. The influence of nitric acid on the radiation chemical behavior of butanal oxime depends on the nitric acid concentration...
April 24, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28420176/establishing-reliable-cu-64-production-process-from-target-plating-to-molecular-specific-tumor-micro-pet-imaging
#6
Qinghua Xie, Hua Zhu, Feng Wang, Xiangxi Meng, Qiushi Ren, Chuanqin Xia, Zhi Yang
Copper-64 is a useful radioisotope for positron emission tomography (PET). Due to the wide range of applications, the demand of (64)Cu with low metallic impurities is increasing. Here we report a simple method for the efficient production of high specific activity (64)Cu using a cyclotron for biomedical application. We designed new equipment based on the plating of enriched (64)Ni as the target, and used automated ion exchange chromatography to purify copper-64 efficiently after irradiation and dissolution of the target in good radiochemical and chemical yield and purity...
April 17, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28419627/instantaneous-conversion-of-11c-co2-to-11c-co-via-fluoride-activated-disilane-species
#7
Carlotta Taddei, Salvatore Bongarzone, Antony Gee
The development of a fast and novel methodology to generate carbon-11 carbon monoxide ([11C]CO) from cyclotron-produced carbon-11 carbon dioxide ([11C]CO2) mediated by fluoride-activated disilane species is described. This methodology allows up to 74% conversion of [11C]CO2 to [11C]CO using commercially available reagents, readily available labware and mild reaction conditions (room temperature). As proof of utility, radiochemically pure [carbonyl-11C]N-benzylbenzamide was successfully synthesized from produced [11C]CO in up to 74% radiochemical yield (RCY) and > 99% radiochemical purity (RCP) in ≤ 10 min from end of [11C]CO2 delivery...
April 17, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28415809/report-on-the-development-and-application-of-pet-ct-in-mainland-china
#8
Yumei Chen, Ruohua Chen, Xiang Zhou, Jianjun Liu, Gang Huang
PURPOSE: To examine the development and application of systems combining positron emission and x-ray-computed tomography systems (PET/CTs) in mainland China. METHODS: Using a questionnaire, we surveyed Chinese medical institutions on a variety topics relating to their PET/CT systems and its use. The respondents had PET/CTs installed and in clinical use before 31 December 2015. We examined the clinical scenarios to which Chinese PET/CTs were applied by reviewing the related Chinese and international literature from the start of 1995 to the end of 2013; these papers were found by searching the Wanfang and PubMed databases, respectively...
March 16, 2017: Oncotarget
https://www.readbyqxmd.com/read/28411627/combination-of-electrospray-ionization-atmospheric-pressure-photoionization-and-laser-desorption-ionization-fourier-transform-ion-cyclotronic-resonance-mass-spectrometry-for-the-investigation-of-complex-mixtures-application-to-the-petroleomic-analysis-of-bio
#9
Jasmine Hertzog, Vincent Carré, Yann Le Brech, Colin Logan Mackay, Anthony Dufour, Ondřej Mašek, Frédéric Aubriet
The comprehensive description of complex mixtures such as bio-oils is required to understand and improve the different processes involved during biological, environmental or industrial operation. In this context, we have to consider how different ionization sources can improve a non-targeted approach. Thus, the Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) has been coupled to electrospray ionization (ESI), laser desorption ionization (LDI) and atmospheric pressure photoionization (APPI) to characterize an oak pyrolysis bio-oil...
May 29, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28403606/halogenated-organic-compounds-identified-in-hydraulic-fracturing-wastewaters-using-ultrahigh-resolution-mass-spectrometry
#10
Jenna L Luek, Philippe Schmitt-Kopplin, Paula J Mouser, William Tyler Petty, Susan D Richardson, Michael Gonsior
Large volumes of water return to the surface following hydraulic fracturing of deep shale formations to retrieve oil and natural gas. Current understanding of the specific organic constituents in these hydraulic fracturing wastewaters is limited to hydrocarbons and a fraction of known chemical additives. In this study, we analyzed hydraulic fracturing wastewater samples using ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) as a nontargeted technique to assign unambiguous molecular formulas to singly charged molecular ions...
April 26, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28402603/an-electrospray-ionization-mass-spectrometry-study-of-azidoacetic-acid-transition-metals-complexes
#11
Vítor S Pinto, Susana C R Marques, Paula Rodrigues, M Teresa Barros, M Lourdes Costa, G John Langley, M Tereza Fernandez, Benedito J C Cabral, M Filomena Duarte, Narciso Couto
RATIONALE: The complexation behavior of transition metals with organic azides by electrospray ionization (ESI) tandem mass spectrometry (MS/MS) is not completely understood. In this study, fragmentation patterns of complex ions having azidoacetic acid coordinated to Ni/Co/Fe were elucidated. The role of transition metals in the mediation of ligand rearrangements in gas phase is experimentally supported. METHODS: The complexation of some transition metals, nickel, cobalt and iron, by azidoacetic acid was studied by means of ESI and MS/MS...
April 12, 2017: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/28401432/feasibility-assessment-of-a-maldi-fticr-imaging-approach-for-the-3d-reconstruction-of-a-mouse-lung
#12
E Ellen Jones, Cristine Quiason, Stephanie Dale, Sheerin K Shahidi-Latham
Matrix assisted laser desorption ionization imaging mass spectrometry (MALDI IMS) has proven to be a quick, robust, and label-free tool to produce two-dimensional (2D) ion-density maps representing the distribution of a variety of analytes across a tissue section of interest. In addition, three-dimensional (3D) imaging mass spectrometry workflows have been developed that are capable of visualizing these same analytes throughout an entire volume of a tissue rather than a single cross-section. Until recently, the use of Fourier transform ion cyclotron resonance (FTICR) mass spectrometers for 3D volume reconstruction has been impractical due to software limitations, such as inadequate capacity to manipulate the extremely large data files produced during an imaging experiment...
April 11, 2017: Journal of the American Society for Mass Spectrometry
https://www.readbyqxmd.com/read/28388197/suppression-of-trapped-energetic-ions-driven-resistive-interchange-modes-with-electron-cyclotron-heating-in-a-helical-plasma
#13
X D Du, K Toi, S Ohdachi, K Y Watanabe, H Takahashi, Y Yoshimura, M Osakabe, R Seki, T Nicolas, H Tsuchiya, K Nagaoka, K Ogawa, K Tanaka, M Isobe, M Yokoyama, M Yoshinuma, S Kubo, S Sakakibara, T Bando, T Ido, T Ozaki, Y Suzuki, Y Takemura
The resistive interchange mode destabilized by the resonant interaction with the trapped energetic ions is fully suppressed when the injected power of electron cyclotron heating exceeds a certain threshold. It is shown for the first time that the complete stabilization of the energetic-particle-driven mode without relaxing the energetic particle (EP) pressure gradient is possible by reducing the radial width of the eigenmodes δ_{w}, especially when δ_{w} narrows to a small enough value relative to the finite orbit width of EP...
March 24, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28384503/manufacturing-and-characterization-of-molybdenum-pellets-used-as-targets-for-99m-tc-production-in-cyclotron
#14
Izabela Cieszykowska, Tomasz Janiak, Tadeusz Barcikowski, Mieczysław Mielcarski, Renata Mikołajczak, Jarosław Choiński, Marek Barlak, Łukasz Kurpaska
The method of (100)Mo metallic target preparation for production of (99m)Tc by proton irradiation in (100)Mo(p,2n)(99m)Tc reaction was demonstrated. For this purpose, pressing of molybdenum powder into pellets and their subsequent sintering in reductive atmosphere were applied. The influence of parameters such as molybdenum mass and time of both pressing and sintering on the (100)Mo target durability was investigated. Under the optimized conditions, (100)Mo metallic pellet targets with density of 9.95±0.06g/cm(3) were obtained...
March 10, 2017: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/28379708/cyclotron-splittings-in-the-plasmon-resonances-of-electronically-doped-semiconductor-nanocrystals-probed-by-magnetic-circular-dichroism-spectroscopy
#15
Kimberly H Hartstein, Alina M Schimpf, Michael Salvador, Daniel R Gamelin
A fundamental understanding of the rich electronic structures of electronically doped semiconductor nanocrystals is vital for assessing the utility of these materials for future applications from solar cells to redox catalysis. Here, we examine the use of magnetic circular dichroism (MCD) spectroscopy to probe the infrared localized surface plasmon resonances of p-Cu2-xSe, n-ZnO, and tin-doped In2O3 (n-ITO) nanocrystals. We demonstrate that the MCD spectra of these nanocrystals can be analyzed by invoking classical cyclotron motions of their excess charge carriers, with experimental MCD signs conveying the carrier types (n or p) and experimental MCD intensities conveying the cyclotron splitting magnitudes...
April 20, 2017: Journal of Physical Chemistry Letters
https://www.readbyqxmd.com/read/28379155/beam-on-imaging-of-short-lived-positron-emitters-during-proton-therapy
#16
Hans Jan Thomas Buitenhuis, Faruk Diblen, Karol Brzezinski, Sytze Brandenburg, Peter Dendooven
In-vivo dose delivery verification in proton therapy can be performed by positron emission tomography (PET) of the positron-emitting nuclei produced by the proton beam in the patient. A PET scanner installed in the treatment position of a proton therapy facility that takes data with the beam on will see very short-lived nuclides as well as longer-lived nuclides. The most important short-lived nuclide for proton therapy is <sup>12</sup>N (Dendooven <i>et al</i> 2015), which has a half-life of 11 ms...
April 5, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28376350/production-of-zr-89-using-sputtered-yttrium-coin-targets-89-zr-using-sputtered-yttrium-coin-targets
#17
Stacy Lee Queern, Tolulope Aramide Aweda, Adriana Vidal Fernandes Massicano, Nicholas Ashby Clanton, Retta El Sayed, Jayden Andrew Sader, Alexander Zyuzin, Suzanne Elizabeth Lapi
An increasing interest in zirconium-89 ((89)Zr) can be attributed to the isotope's half-life which is compatible with antibody imaging using positron emission tomography (PET). The goal of this work was to develop an efficient means of production for (89)Zr that provides this isotope with high radionuclidic purity and specific activity. We investigated the irradiation of yttrium sputtered niobium coins and compared the yields and separation efficiency to solid yttrium coins. The sputtered coins were irradiated with an incident beam energy of 17...
March 23, 2017: Nuclear Medicine and Biology
https://www.readbyqxmd.com/read/28374758/magneto-dendrite-effect-copper-electrodeposition-under-high-magnetic-field
#18
Makoto Miura, Yoshinobu Oshikiri, Atsushi Sugiyama, Ryoichi Morimoto, Iwao Mogi, Miki Miura, Satoshi Takagi, Yusuke Yamauchi, Ryoichi Aogaki
Ionic vacancy is a by-product in electrochemical reaction, composed of polarized free space of the order of 0.1 nm with a 1 s lifetime, and playing key roles in nano-electrochemical processes. However, its chemical nature has not yet been clarified. In copper electrodeposition under a high magnetic field of 15 T, using a new electrode system called cyclotron magnetohydrodynamic (MHD) electrode (CMHDE) composed of a pair of concentric cylindrical electrodes, we have found an extraordinary dendritic growth with a drastic positive potential shift from hydrogen-gas evolution potential...
April 4, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28372442/design-of-a-75-140-ghz-high-pass-printed-circuit-board-dichroic-filter
#19
Dong Hwi Kim, Wahab Mohyuddin, Dong Sik Woo, Hyun Chul Choi, Kang Wook Kim
A new high-performing PCB (Printed Circuit Board) dichroic filter, which can be used for the KSTAR (Korea Superconducting Tokamak Advanced Research) electron cyclotron emission imaging system, is proposed. The current dichroic filter consists of a triangular lattice array of circular holes on the 6-mm thick metal plate, while circular hole spacing limitation caused relatively narrow passband (∼20 GHz). On the other hand, the proposed PCB dichroic filter utilizes the inexpensive commercial PCB fabrication process with a flexible adjustment of circular hole spacing...
March 2017: Review of Scientific Instruments
https://www.readbyqxmd.com/read/28372426/heavy-ion-linear-accelerator-for-radiation-damage-studies-of-materials
#20
Sergey V Kutsaev, Brahim Mustapha, Peter N Ostroumov, Jerry Nolen, Albert Barcikowski, Michael Pellin, Abdellatif Yacout
A new eXtreme MATerial (XMAT) research facility is being proposed at Argonne National Laboratory to enable rapid in situ mesoscale bulk analysis of ion radiation damage in advanced materials and nuclear fuels. This facility combines a new heavy-ion accelerator with the existing high-energy X-ray analysis capability of the Argonne Advanced Photon Source. The heavy-ion accelerator and target complex will enable experimenters to emulate the environment of a nuclear reactor making possible the study of fission fragment damage in materials...
March 2017: Review of Scientific Instruments
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