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[en] In the present study, the compound N-benzoyl-N',N'-diheptadecylthiourea has been evaluated as carrier for the extraction of toxic metals. Liquid-liquid extraction experiments of Hg(II), Cd(II) and Pb(II) in nitrate media were performed, and neither cadmium nor lead were extracted in the pH range from 2 to 6, showing benzoylthiourea derivative as a high selective extractant for mercury. A solid supported liquid membrane system has been developed for mercury permeation using 0.3 M thiourea as stripping agent. Several parameters affecting liquid membrane performance are evaluated, such as the organic solvent, where the best results are obtained with a mixture decaline:cumene, the feed composition and the length of alkyl chains in the carrier. The choice of the polymeric support material used to contain the liquid membrane, as well as its physical characteristics, was found to be crucial to ensure an effective metal transport across the liquid membrane. The application of this SLM in hollow fiber supported liquid membrane (HFSLM) configuration allowed the enrichment of solutions with low mercury content. High preconcentration factors are obtained, showing the feasibility of using the developed system as an effective technique for analytical applications
[en] Full text: At the result of research action of salts of some metals on living organisms their preventive and therapeutic action is revealed. It was revealed, that metals in structure of organic complex connections are less toxic, than as inorganic salts. Presence of organic ligand gives metallic-complexes lipophilically, will neutralize electrostatistical charges of metals therefore their transport through cellular membranes is strongly facilitated. In this connection rather expedient study of radioprotector properties of trivalent metals and their complexes is represented. Use of iron as a radioprotector is caused with its ability to steady complexing biogenic character. As objects of researches are taken seeds drought-resistant firm of wheat Triticum L. Seeds subjected to the general uniform scale of irradiation-from a source 60 Co and gamma to installation Rkhundat average capacity of a doze of radiation dose rate (D R=0,024 Gy/s). Before the irradiation seeds have been processed pyrocatechol, iron pyrocatechol, thiocarbamide, iron-thiocarbamide, rutin and iron rutin at concentration 102 M. For synthesis of complexes used chloride of iron (III), thiocarbamide, pyrocatechol marks a.p.a.. Routines (3- ramnoglycoside-3,5,7,3,4-penta-oksi-flavone, chartreuse fine-grained a powder) have received from (Sophora japonica L.): Synthesis complexes of iron carried out by the following technique: stoichiometric quantity of thiocarbamide, pyrocatechol and routine dissolved separately in 50 ml isopropyl alcohol. A solution of chloride of iron (III) deposits dropped out, separated, dried up to constant weight was added to the received solutions in the portions at hashing.
[en] Synthesis of the 99mTc(CO)3-trovafloxacin dithiocarbamate (99mTc(CO)3-TVND) complex and biological characterization in artificially Staphylococcus aureus (S. aureus) infected rats model was assessed. The suitability of the complex was evaluated and compared with 99mTcN-TVND, in terms of radiochemical immovability in saline, in vitro permanence in serum, in vitro binding with S. aureus and biodistribution in Male Sprague-Dawley rats (MSDR). After 30 min of the reconstitution both the complexes showed maximum radiochemical stabilities in saline and remain more than 90% stable up to 120 min. However the 99mTc(CO)3-TVND showed to some extent higher stability than 99mTcN-TVND complex. In serum 1.75% less de-tagging was observed than 99mTcN-TVND complex. Both the complexes showed saturated in vitro binding with S. aureus and no significant difference were observed between the uptakes. Six fold uptakes were noted in the infected muscle as compared to the inflamed and normal muscles of the MDSR. The uptake of the 99mTc(CO)3-TVND in infected muscle of the MSDR was 2.25% high as compared to the 99mTcN-TVND complex. Based on radiochemical stabilities in saline, serum, in vitro binding with MRSA and significantly higher uptake in the infected muscle, we recommend both the complexes for in vivo investigation of the MRSA infection in human. (author)
[en] In the current investigation tosufloxacin (TSN) was derivatized to its dithiocarbamate (TSND) derivative and its radiolabeling with technetium-99m using [99mTc(CO)3(H2O)3]+ precursor. The labeled TSND (99mTc(CO)3-TSND) was radiochemically characterized in saline and serum and biologically its in vitro binding with Proteus mirabilis (P. mirabilis) and biodistribution in male Wister rats (MWR) artificially infected with live and heat killed P. mirabilis. Radiochemically a stable radio-tricarbonyl TSND complex was observed with a maximum stability of 98.15 ± 0.32% and it remained more than 90% up to 4 h after reconstitution. The stability decreased to 91.00 ± 0.30% from 98.15 ± 0.32% within 4 h. In serum at 37 deg C the growth of some unwanted side product decreased the stability by 15.65% within 16 h. The complex showed saturated in vitro binding with P. mirabilis up to 78.50% (90 min). In MWR infected with live P. mirabilis the percent (%) uptake of the complex in blood, liver, spleen, stomach, intestines and kidneys were almost similar to the MWR infected with heat killed. However, the % accumulation of the complex in the infected muscle was six times higher than in the inflamed and normal muscle in MWR infected with live P. mirabilis. On the basis of immovability of the 99mTc(CO)3-TSND complex in normal saline, in vitro permanence in serum, saturated in vitro binding with P. mirabilis and six fold uptake in the infected muscle of the MWR infected with live P. mirabilis as compared to the normal muscle, the suitability of the 99mTc(CO)3-TSND complex is established as a promising infection radiotracer. (author)
[en] A radiochemical method to isolate 99Mo from 132Te both produced in the fission of 235U has been developed. The methods is based on the formation of a cationic complex of tellerium with thiourea in acid medium which is retained (98.7 +- 0.5)% on a cation exchange resin (Dowex 50W-X8, 100 - 200 mesh) while (99.8 +- 0.05)% 99Mo passes through it, due to the non formation of such complex in the same experimental conditions. The radionuclidic purity of the separated 99Mo verified by using gamma spectrometry was found to be suitable for the preparation of 99Mo - 99 sup (m)Tc generators. The retention of 99Mo on an alumina column as function of ph was investigated. the best pH range for this purpose was found to be between 4.0 - 4.5. the 99Mo - 99mTc generator was prepared. the elution of99mTc was carried out with physiologic saline solution. The radionuclidic purity of the eluate was found suitable and the product can be used for Nuclear Medicine applications. (author)
[pt]Desenvolveu-se um metodo radioquimico para a separacao de 99Mo do 132Te obtidos na fissao do 235U que se baseia na complexacao do telurio com tioureia, em meio acido. O telurio forma complexo cationico com a tioureia, enquanto que tal nao ocorre com o molibdenio nas mesmas condicoes experimentais. Os resultados obtidos mostraram que a retencao do complexo telurio-tioureia na resina cationica Dowex-50W-X8, 100-200 mesh e (98,7 ± 0,5)%, sendo que (99,8 ± 0,05)%, do 99Mo sao encontrados no efluente. O 99 Mo separado que foi analisado por espectrometria gama apresentou pureza radionuclidica satisfatoria pura uso na preparacao de geradores de 99Mo - 99mTc. Estudou-se tambem a retencao do 99Mo em colunas de alumina em funcao do ph observando-se que a retencao maxima ocorre no intervalo de Ph entre 4,0 e 4,5. Preparou-se o generador 99Mo - 99mTc e eluiu-se o 99mTc com solucao fisiologica. A pureza radionuclidica do eluido foi de 100% aproximadamente, estando de acordo com as Farmacopeias Internacionais para uso em aplicacoes medicas. (autor)
[en] The radioprotective effects of o-allylthioureidohenzoic acid (A TB), N-allvl-N '-2- pyridyl-thiourea (A-2-PTU), N-phenyl-N'-2-pyridyl-thiourea (P-2-PTU) to pea and soybean were studied. It was demonstrated that A-2-PTU and P-2-PTU have high radioprotective effect, expressed by lower lethality and considerably enhanced percentage of germinating and surviving plants. The experiments conducted showed that the A TB radioprotective effect manifested in respect to phytohormones was related also with the morphological changes in roots and the hypocotyl.
[en] A new dansyl-diethylenetriamine-thiourea conjugate (DT) for detection of Hg"2"+ ions in aqueous solution has been theoretically designed and compared to our previously published results. The synthetic path, the optimized geometric structure and the characteristics of the DT were found by the theoretical calculations at the B3LYP/LanL2DZ level. Accordingly, the DT can react with Hg"2"+ ion to form a product with quenched fluorescence. It is remarkable that the experimental results are in an excellent agreement with the theoretically evaluated data. (author)