Electrochemical separation of 90-yttrium in the electrochemical 90Sr/90Y generator and its use for radiolabelling of DOTA-conjugated somatostatin analog [DOTA0, Tyr3] octreotate

Radiopharmaceuticals based on 90Y are widely used in the treatment of malignant deseases. In order to meet the requirements for their future application, a 90Sr/90Y generator was developed and 90Y eluted from this locally produced generator was used for the radiolabelling of the DOTA-conjugated somatostatin analog [DOTA0,Tyr3] octreotate and the preparation of [90Y-DOTA0,Tyr3] octreotate (90Y-DOTATATE) for peptide receptore radionuclide therapy. 90Sr/90Y generator was based on the electrochemical separation of 90Y from 90Sr in a two-cycle electrolysis procedure. Three electrode cells were used to perform both electrolyses. In both cycles, working electrodes were kept on constant potential. The pH of the solution was adjusted to 2.7 of the value before the electrolyses. The radionuclidic purity of the 90Y solution was analysed by ITLC and extraction paper chromatography. The labelling of peptide (100 mg DOTATATE) with 90YCl3 was performed at 95°C for 30 minutes. Radiochemical purity was determined by HPLC and chromatographic separation, using a solid SepPak C-18 column. Results obtained confirmed the efficiency of our electrochemical separation technique and quality control methods for 90Y. The achieved efficiency of the 90Sr/90Y generator above 96% of the theoretical value represents a good basis for the further development of this generator. The labelling of the DOTATATE with 90Y exhibited a high efficiency, too: there was less than 1% of 90Y3+in the 90Y-DOTATATE

Synthesis and characterization of (Ba,Yb) doped ceria nanopowders

Nanometric size (Ba, Yb) doped ceria powders with fluorite-type structure were obtained by applying selfpropagating room temperature methods. Tailored composition was: Ce0.95−xBa0.05YbxO2−δ with fixed amount of Ba − 0.05 and varying Yb content “x” from 0.05 to 0.2. Powder properties such as crystallite and particle size and lattice parameters have been studied. Röntgen diffraction analyses (XRD) were used to characterize the samples at room temperature. Also, high temperature treatment (up to 1550°C) was used to follow stability of solid solutions. The mean diameters of the nanocrystals are determined from the full width at half maxima (FWHM) of the XRD peaks. It was found that average diameter of crystallites is less than 3 nm. WilliamsonHall plots were used to separate the effect of the size and strain in the nanocrystals

Characterization of bentonite clay from “Greda” deposit

Based on mineralogical and technological investigations of the deposit “Greda” important characteristics of bentonite clay were determined. Representative samples of the deposit were characterized with X-ray diffraction, low-temperature nitrogen adsorption, chemical analysis, differential thermal analysis and scanning electron microscopy. It was determined that the main mineral is montmorillonite and in subordinate quantities kaolinite, quartz and pyrite. The chemical composition generally shows high silica and alumina contents in all samples and small quantities of Fe3+, Ca2+ and Mg2+ cations. Based on technological and mineralogical research, bentonite from this deposit is a high-quality raw material for use in the ceramic industry

Syntheses of Pb-ceramic from zeolite precursors: XRPD refinement and SEM/EDS analysis

The Pb-ceramic was syntheses by process of thermally induced phase transformation of Pb-exchange LTA and FAU zeolites. Both frameworks collapse into amorphous intermediate products after heating between 600 and 650 o C. Prolonged heating of the intermediate product over 1100o C results directly in formation of a disorder Pb feldsparLTA [a =8.4171(4) Å, b=13.0532(4) Å, c=7.1722(4) Å, β=115.35(3)°] and Pb-feldsparFAU [a=8.426(4) Å, b=13.0608(4) Å, c=7.1773(4) Å, β=115.36(3)°] phase. The phase conversions in the temperature range investigated were followed by thermal (DTA/TGA), XRPD, and SEM/EDS analyses. The results showed that the Pbceramic could be obtained by process of thermally induced phase transformation of Pbexchange zeolites.I Serbian Ceramic Society Conference : 1CSCS-2011 : program and the book of abstracts; March 17-18, 2011; Belgrad

Application of ascorbic acid as a radiolytic stabilizer for [131I]mibg

In this paper the results of a stability of [131I]mIBG, stored under various conditions, are presented. The stability was followed during 14 days. The most important radiochemical impurity in [131I]mIBG is free [131I]iodide, formed by radiolysis. The results indicate that the rate of radiolytic decomposition of [131I]mIBG is much slower at higher concentration of ascorbic acid (20 mg/mCi) and at lower storage temperature (40C)

Luminescence properties of Eu3+ activated Y2MoO6 powders calcined at different temperatures

In the last decade, an immense progress has been made in white LEDs, mainly due to the development of red-emitting phosphors. In this paper, we report on the synthesis of Eu3+ activated Y2MoO6 by a self-initiated and self-sustained method. The obtained powder was calcined at various temperatures in the 600–1400 °C range and examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and photoluminescence spectroscopy (PL). The results revealed that all powders are single phase Y2MoO6:Eu3+, with particle size in the nanorange at lower treatment temperatures (600 and 800 °C) and in the microrange at higher calcination temperatures (1000–1400 °C). The obtained powders are promising materials for white light-emitting diodes as they can efficiently absorb energy in 324–425 nm region (near-UV to blue light region) and emit at 611 nm in the red region of the spectrum, while exhibiting high thermal and chemical stability

Physicochemical evaluation of Technetium-99m complexes with baclofen

The 99mTc-labeling of baclofen (Bac), a muscle relaxant, as well as physicochemical properties of the labeled compounds are investigated. Two different approaches for the labeling with 99mTc have been studied: direct reduction with tin(II)chloride and the 'organometallic approach' using [99mTc(CO)3(H2O)3] + precursor. The direct labeling approach was not successful and the yield was poor. The use of [99mTc(CO)3(H2O)3]+ precursor pointed at the formation of 99mTc(I) coordinated complexes with high yield. In this approach, pH didn’t influence the yields. Promising results of in vitro experiments suggest that 99mTc(I)-baclofen may be of potential use for diagnosis of some central nervous system disorders.Physical chemistry 2012 : 11th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 201

99mTc-complex of novel diamine-dioxime ligand

Novel diamine-dioxime ligand, 4,7-diaza-3,8-diethyldecane-2,9-dione bis oxime (LH2), derivative of hexamethyl-propylene amine oxime (HMPAO), was synthesized in order to develop new brain perfusion imaging agent, based on 99mTc(V) complexes. The 99mTc(V)-d,l-HMPAO complex is well-known radiopharmaceutical for brain imaging. The structures of the synthesized compound were characterized by UV-Vis, IR, 1 H NMR and 13C NMR. The procedure for radiolabeling of diamine-dioxime with 99mTc was developed and radiolabeling yield of the 99mTc-complex was followed by paper and thin-layer chromatography. The maximum radiolabeling yield was obtained when the reactions were carried out at pH~9 within 10 min at room temperature (RT). Biodistribution studies on rats has shown significant uptake of 99mTc-complex (2.1% ID), 2 min after injection.Physical chemistry 2012 : 11th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 201

Synthesis of silver doped hydroxyapatite nanospheres using Ouzo effect

Nanoemulsion technique, based on Ouzo effect, was applied for synthesis of the pure and silver doped (2.5 and 5 mol%) calcium hydroxyapatite (HAp). After calcination at 500 degrees C fully crystallized powders were obtained. X-ray powder diffraction analysis accompanied with Rietveld refinement revealed that the synthesized powders were single-phase hydroxyapatite. Raman spectroscopy also confirmed that the synthesized powders were single-phase. The obtained HAp particles were spherical in shape and their sizes were in the nanometer range which was revealed by field emission scanning electron microscopy analysis (FESEM). The successful synthesis of the single-phase Ag doped HAp showed that nanoemulsion method is a simple technique for obtaining pure and doped hydroxyapatite nanospheres

Preparation of 90Y-Labeled Tin Fluoride Colloid for Radiosynovectomy

In this study, tin fluoride colloid (SnF-c) was prepared, labeled with 90Y and characterized with respect to its physicochemical properties. Particle size of SnF-c, at constant concentration of SnF2, was dependent on pH, concentration of NaF, temperature and time. The particle size of SnF-c decreased with an increase in NaF concentration and a decrease in reaction mixture pH. Radiolabeling yield of 90Y-SnF-c at higher temperature increased and it was greater than 98% for the preparation at 95 oC. Due to high labeling yield and stability, 90Y-SnF-c might be a promising agent for radiosynovectomy.Physical chemistry 2012 : 11th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 201