Production, biodistribution, and dosimetry of (47)Sc-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene phosphonic acid as a bone-seeking radiopharmaceutical.

In this study 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene phosphonic acid (DOTMP) was used as the polyaminophosphonic acid carrier ligand and the therapeutic potential of the bone seeking radiopharmaceutical (47)Sc-DOTMP was assessed by measuring its dosage-dependent skeletal uptake and then the absorbed radiation dose of human organs was estimated. Because of limited availability of (47)Sc we performed some preliminary studies using (46)Sc. (46)Sc was produced with a specific activity of 116.58 MBq/mg (3.15 mCi/mg) and radionuclide purity of 98%. (46)Sc-DOTMP was prepared and an activity of 1.258 MBq (34 µCi) at a chelant-to-metal ratio of 60:1 was administered to five groups of mice with each group containing 3 mice that were euthanized at 4, 24, 48, 96 and 192 h post administration. The heart, lungs, liver, spleen, kidneys, intestine, skin, muscle, and a femur were excised, weighed, and counted. The data were analyzed to determine skeletal uptake and source organ residence times and cumulated activities for (47)Sc-DOTMP. (46)Sc-DOTMP complex was prepared in radiochemical purity about 93%. In vitro stability of complex was evaluated at room temperature for 48 h. Biodistribution studies of complex in mice were studied for 7 days. The data were analyzed to estimate skeletal uptake and absorbed radiation dose of human organs using biodistribution data from mice. By considering the results, (47)Sc-DOTMP is a possible therapeutic agent for using in palliation of bone pain due to metastatic skeletal lesions from several types of primary cancers in prostate, breast, etc.

Ionic liquids for simultaneous preconcentration of some lanthanoids using dispersive liquid-liquid microextraction technique in uranium dioxide powder.

Ionic liquids in a dispersive liquid-liquid microextraction technique were used for determination of lanthanoids such as samarium, europium, gadolinium, and dysprosium in uranium dioxide powder. In this process, an appropriate mixture of extraction solvent and disperser is rapidly injected into an aqueous sample containing samarium, europium, gadolinium, and dysprosium ions complexes with 1-hydroxy-2, 5-pyrrolidinedione, and consequently a cloudy solution is formed. It consists of fine droplets of extraction solventwhich are dispersed entirely into the aqueous phase. After centrifugation of this solution, the whole enriched phase was determined by inductively coupled plasma optical emission spectrometry. In the present work, the preconcentration factor, limit of detection, and relative standard deviation were investigated for samarium, europium, gadolinium, and dysprosium in uranium dioxide powder.