Preparation of concentrated rhenium solutions

The conditions of the desorption of rhenium from the anion exchange resin Dowex 1×8 by nitric acid were determined. The solution (5×10-3 mol/dm3 Re in 0.15 mol/dm3 NaCl) was passed through the column containing 0.1 g of the resin. The total sorbed amount of rhenium was 200 mg/g of the resin. It was then eluted by nitric acid in the concentration range of 0.16-7.2 mol/dm3 . The most favourable elution profile was found with 3.0 mol/dm3 HNO3. Over 77% of the total rhenium was desorbed with 5 ml of this eluence. Over 95% of the sorbed rhenium was recovered by using 20 ml of nitric acid in the concentration range of 0.9-7.2 mol/dm3 .Physical chemistry 2006 : 8th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 26-29 September 200

Radionuklidni generatori za dobijanje tehnecijuma-99m i renijuma-188

The paper deals with production and application of open radioactive sources in modern diagnostic and therapeutic nuclear medicine. In principle, besides adequate physical, chemical and biological properties a reliable route for the routine production of both radionuclide and radiopharmaceutical should be on disposal. The favorite route are radionuclidic generators as they enable simple production of shorter-lived radionuclides at relatively low costs. The main radionuclide in diagnosis is technetium-99m. Its advantages are favorable nuclear properties, availability of large activities of high quality 99m Tc at reasonable prices by using (n,f)99Mo/ 99m Tc generators and versatile chemistry. It is used in the investigation of practically all organs and tissues in the human body. Among the beta- emitters the radionuclides of rhenium have been recently proposed as suitable candidates for therapeutic applications. The most important is 188Re which is obtained from 188W/ 188Re generator. Some of the important radiopharmaceuticals labeled with rhenium radionuclides used for certain specific indications are also shown. The activities performed in the Laboratory for Radioisotopes (Vinča Institute of Nuclear Sciences) are also enclosed.Prikazani su neki od najvažnijih aspekata proizvodnje i primene otvorenih izvora radioaktivnog zračenja u dijagnostičkoj i terapijskoj nuklearnoj medicini. Pored fizičkih, bitne su i hemijske i biohemijske osobine datog radionuklida odnosno radiofarmaceutika. Uslov za redovnu primenu su i dostupnost, kvalitet i cena. Radionuklidni generatori predstavljaju vrlo pogodan izvor dobijanja radionuklida kraćih vremena poluraspada. Najvažniji dijagnostički radionuklid je 99m Tc. Odlične fizičke osobine, visok kvalitet i laka dostupnost po prihvatljivim cenama korišćenjem molibden-99/tehnecijum- 99m generatora i razvijena hemija doveli su do toga da ovaj radionuklid postane praktično nezamenjiv u ispitivanju skoro svih organa i tkiva u ljudskom organizmu. Dati su savremeni trendovi u razvoju proizvodnje radionuklida i radiofarmaceutika za primenu u terapijske svrhe. Prikazani su načini dobijanja radionuklida renijuma (186Re i 188Re) sa posebnim naglaskom na 188W/ 188Re generatoru. Dati su hemijski oblici i indikacije za primenu nekih radioaktivnih lekova obeleženih ovim radionuklidima. Prikazana su istraživanja sprovedena u Laboratoriji za radioizotope (Institut za nuklearne nauke «Vinča»)

Separation of rhenium (VIII) from tungsten (VI)

Examined were the conditions for an effective separation of tungsten(VI) and rhenium(VII) on alumina if the solution of 0.20 mol dm-3 NaCl, pH=2-6, is used as the aqueous phase. Under the given experimental conditions alumina was found to be much better adsorbent for tungsten than for rhenium. The breakthrough and saturation capacities of alumina at pH = 2 are 24 and 78 mg W/g Al2O3, respectively. With the increase of pH these values decrease. So, at pH = 6 they are only 4 and 13 mg W/g Al2O3, respectively. The elution volume for rhenium for the given column dimensions and the quantity of the adsorbent, is about 16 ml. These results were confirmed by the experiments of the radiochemical separations. Tungsten-187 remains firmly bound to alumina. The radionuclidic purity of the eluted 186,188 Re at pH = 2 is very high.Physical chemistry 2004 : 7th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 21-23 September 200

RADIONUCLIDIC GENERATORS FOR THE PRODUCTION OF TECHNETIUM-99M AND RHENIUM-188 UDC 539.1

Abstract. The paper deals with production and application of open radioactive sources in modern diagnostic and therapeutic nuclear medicine. In principle, besides adequate physical, chemical and biological properties a reliable route for the routine production of both radionuclide and radiopharmaceutical should be on disposal. The favorite route are radionuclidic generators as they enable simple production of shorter-lived radionuclides at relatively low costs. The main radionuclide in diagnosis is technetium-99m. Its advantages are favorable nuclear properties, availability of large activities of high quality 99m Tc at reasonable prices by using (n,f) 99 Mo / 99m Tc generators and versatile chemistry. It is used in the investigation of practically all organs and tissues in the human body. Among the betaemitters the radionuclides of rhenium have been recently proposed as suitable candidates for therapeutic applications. The most important is 188 Re which is obtained from 188 W / 188 Re generator. Some of the important radiopharmaceuticals labeled with rhenium radionuclides used for certain specific indications are also shown. The activities performed in th

Separation of tungsten and rhenium on alumina in dynamic conditions

The separation of tungstate and perrhenate anions on alumina from aqueous solutions of sodium chloride was investigated in dynamic conditions. The breakthrough curves for W and Re as the function of the ratio of their concentrations in the solution, were determined. The flow rate (3 ml/min), pH 2 and NaCl concentration (0.15 mol/l) were kept constant throughout the experiments. The breakthrough capacities Q(0.05), the capacities at C/C-0 = 0.5, the total column sorption capacities Q(0.9) and the utilization degrees or column efficiencies E, were determined. According to the obtained data the separation factors alpha(W/Re) = Q(w)/Q(Re) were calculated

Kvalitet potpunih smeša za ishranu različitih kategorija pasa na tržištu Republike Srbije

Imajući u vidu nedostatak jasno definisanih i propisanih uslova kvaliteta koji se odnose na segment proizvodnje hrane za ishranu pasa, neophodno je obezbediti stalni i višestepeni monitoring pri njenoj proizvodnji i prometu. Na opisani način dobijaju se pouzdani podaci o sastavu i kvalitetu hrane za pse, a istovremeno potrošaču se pruža osećaj sigurnosti i poverenja prema traženom proizvodu. U ogledu je izvršena analiza većeg broja industrijski proizvedenih potpunih smeša domaće proizvodnje, kao i uvoznog porekla, namenjenih ishrani različitih kategorija pasa (Junior i Adult). Smeše su uzorkovane direktno iz prometa, u originalnom pakovanju, sa pratećom deklaracijom proizvođača. Osnovni hemijski sastav, kao i prisustvo mikro i makroelemenata u uzorcima hrane određeni su standardnim analitičkim metodama, a dobijeni rezultati poređeni su sa deklarisanim vrednostima. Hemijskom analizom uzoraka hrane utvrđena su značajna odstupanja u odnosu na deklarisani sadržaj ispitivanih vrednosti. Korišćenjem navedenih smeša psi ne zadovoljavaju potrebe u osnovnim hranljivim materijama, kao i u pogledu unosa mikro i makroelemenata, što ukazuje na greške u proizvodnji ili na nedovoljno poznavanje stvarnih potreba pasa. Neophodno je pristupiti kontinuiranoj, sistemskoj edukaciji, proizvođača hrane za ishranu pasa, kao i samih vlasnika.Having in mind the lack of clearly defined and prescribed quality conditions related to the segment of dog feed production, it is necessary to provide constant and multi-level monitoring in its production and trade. In the described way, reliable data on the composition and quality of dog feed can be obtained, and at the same time the consumer is given a sense of security and trust towards the requested product. In this experiment a large number of industrially produced complete mixtures of domestic production, as well as imported origin, intended for feeding different categories of dogs (Junior and Adult) have been analyzed. The mixtures were sampled directly from the market, in the original packaging, with the accompanying declaration provided by the manufacturer. The basic chemical composition, as well as the presence of micro and macroelements in feed samples, were determined by standard analytical methods, and the obtained results were compared with declared values. Chemical analysis of feed samples revealed significant deviations in relation to the declared content of the tested values. By using these mixtures, dogs cannot meet the requirements for basic nutrients, as well as for intake of micro and macro elements, which indicates errors in production or insufficient knowledge of the real needs of dogs. It is necessary to provide continuous, systemic education, for producers of dog feed, as well as the owners themselves.Zbornik radova i kratkih sadržaj