Separation of trace elements,In(III), Sn(IV), Sb(V) and Te(IV) by adsorption on activated carbon and graphite

Adsorption behaviour of trace elements, In(III), Sn(IV), Sb(V) and Te(IV) on activated carbon and graphite powder was studied. Adsorption characteristics of the ions enabled the separation of In(III)–Sn(IV), Sn(IV)–Sb(V) and Sb(V)–Te(IV) pairs. Applications to practical separation, milking of^113mIn from¹¹³Sn, removal of tin impurity from¹¹⁹Sb, and milking of¹¹⁹Sb from^119mTe, are presented.     

Radiochemical investigation of the electron exchange reaction between tin(II) and tin(IV) in hydrochloric acid solutions

This paper is concerned with the study of isotope exchange reaction between Sn(II) and Sn(IV) in hydrochloric acid solutions. The kinetics of the exchange reaction of tin in these solutions were studied by extraction of Sn(IV)-hydroxyquinolate into chloroform.¹¹³Sn tracer, initially in the Sn(IV) state, was used. The rate of exchange reaction was determined at 22°C in a wide range of hydrochloric acid concentrations (2.8–12M). The dependence of the exchange rate on the concentration of chloride and hydrogen ions in these solutions (ionic strength: I∼8 and I∼12) are given. The activation energy dependence on chloride ion concentration at I∼12 was determined. The possible mechanism of the exchange reaction between tin(II) and tin(IV) is discussed on the basis of these data.     

113Sn-113mIn generator with a glass beads column

The adsorption characteristics of ¹¹³Sn(IV) and ^113mIn(III) on glass beads from NaCl solutions have been studied. On the basis of these studies, ¹¹³Sn-^113mIn generator has been prepared by adsorbing ¹¹³Sn on the glass beads column. ^113mIn has been eluted by the 0.16M NaCl solution with pH 3.0, remaining ¹¹³Sn adsorbed on the glass beads. The yield of ^113mIn has been about 73% in the first 6 ml of eluate, while the breakthrough of ¹¹³Sn has been about 0.042%.     

Zinn(IV)-Komplexe mit dreizähnigen diaciden Liganden — 119Sn-NMR und 119mSn-Mössbauer-spektroskopische Untersuchungen

Tin(IV) Complexes with Tridentate Diacidic Ligands — ¹¹⁹Sn NMR and ^119mSn Mössbauer Studies The tin(IV) chelates of tridentate diacidic azomethines of acetylacetone resp. salicylaldehyde with benzoylhydrazine, thiobenzoylhydrazine, 2-hydroxyaniline and 2-mercaptoaniline as well as with the ligands 2-(2′-hydroxy-4-methylphenyl)-6-(2″-hydroxyphenyl)pyridine, 2-(2′-hydroxyphenyl)-8-quinolinol and 2.6-diphenacylpyridine were synthesized. The compounds were characterized by IR-, UV/VIS-, MS-, ¹¹⁹Sn NMR and ^119mSn Mössbauer spectroscopy. They exist as a mixture of geometrical isomers.     

Tetrakis Sn(IV) alkoxides as novel initiators for living ring‐opening polymerization of lactides

The use of tetrakis Sn(IV) alkoxides as highly active initiators for the ring‐opening polymerization of D ,L ‐lactide is reported. The activities of prepared Sn(IV) tetra‐2‐methyl‐2‐butoxide, Sn(IV) tetra‐iso‐propoxide, and Sn(IV) tetra‐ethoxide were compared to a well‐known ring‐opening polymerization initiator system, Sn(II) octoate activated with n‐butanol. All polymerizations were conducted at 75 °C in toluene. The activities of tetrakis Sn(IV) alkoxides grew in order of increasing steric hindrance, and the bulky Sn(IV) alkoxides showed higher activity than the Sn(II) octoate/butanol system. The living character of the polymerization was demonstrated in homopolymerization of D ,L ‐lactide and in block copolymerization of L ‐lactide with ?‐caprolactone. ¹H, ¹³C, and ¹¹⁹Sn NMR were used to characterize the prepared Sn(IV) alkoxides and the polymer microstructure, and size exclusion chromatography was used to determine the molar masses as well as the molar‐mass distributions of the polymers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1901–1911, 2004     

Separation of <Superscript>113m</Superscript>In from <Superscript>113</Superscript>Sn based on activated carbon used as column matrix

The activated carbon was prepared by using corncobs and characterized by sorpatometer for using as an exchanger material to separate the generated ^113mIn from ¹¹³Sn and ^124,125Sb. To optimize the separation process, the different parameters like acetone percentage, HCl concentration were studied. The exchange capacity of Sn(IV) is 7.6 meq/g onto the activated carbon and the elution efficiency of ^113mIn > 80% by using 10 mL of 0.2 M HCl-80% acetone with flow rate 1 mL/min. The radionuclidic purity and radiochemical purity of the eluted ^113mIn were examined and clarified the presence of ^124,125Sb with relatively high level as radio impurities, so further separation was carried out by using Dowex 1×8 as an anion exchanger below the activated carbon matrix on the same separation column to adsorb the ¹¹³Sn and ^124,125Sb, which escape from the activated carbon matrix.     

Zirconium silicotungstate matrix as a prospective sorbent material for the preparation of <Superscript>113</Superscript>Sn/<Superscript>113m</Superscript>In generator

The zirconium silicotungstate (ZrSiW) was studied as an effective sorbent material to be used in the ¹¹³Sn/^113mIn generator. The results elucidated that the distribution coefficient of ¹¹³Sn (3700 mL/g) is greater than ^113mIn (275 mL/g) from 0.1 M HCl acid solution to the ZrSiW material. The maximum sorption capacity of Sn (IV) was found to be 33 mg per gram ZrSiW (~?0.3 mmol/g). The elution yield of ^113mIn was found to be >?78?±?6.4% with an acceptable purity of radionuclidic and radiochemical (≥?99.99 and 96.8%, respectively). The rigorous separation of ^113mIn from the ¹²⁵Sb was carried out due to its long half-life (2.758 years) and beta emission that causes tissue damage. Zr, W and Si levels are below the permitted limit in the ^113mIn eluate.     

99mTc complexes of 1,3-propanedithiol derivatives

The labelling of 1,3-n alkylpropanedithiols and of 15-/1,3-dimercapto 2-propyl/ pentadecanoic acid by^99mTc has been performed by an exchange reaction with the hexachlorotechnetate ion^99mTcCl ₆ ^2– and by reduction of^99mTcO ₄ ^– with Sn/II/ in the presence of the ligand. The biological distribution of the exotechnetium complexes obtained by the latter method in mouse does not reveal a high tropism of these labelling compounds in relation to a particular tissue.     

Synthesis of radiolabelled compounds

Compounds labelled with radioisotopes such as¹⁴C,³H,³²P,³⁵S and¹²⁵I, are essential tools for research and especially in the life sciences. Syntheses can be directed to isotopic labelling or to non-isotopic labelling. In isotopic labelling a compound is labelled with an isotope of an element already present in the compound whereas non-isotopic labelling is achieved with an isotope is foreign to the material or compound being labelled. This paper reviews the properties of the more important and commonly used radioisotopes in research and methods currently employed for the synthesis of radiolabelled compounds. The relative ease of measurement of radioactivity in large numbers of samples, when compared for example with the measurement of mass, and the great sensitivity with which very small quantities of radioactive compounds can be accurately measured, has resulted in the widespread need and use of radiolebelled compounds. Methods for the practicable labelling of compounds for use as radiotracers all into three main categories, namely, chemical systhesis, biochemical methods and isotope exchange reactions. Examples are chosen to illustrate these methods for the labelling of amino acids, peptides, proteins, carbohydrates, lipids, neurochemicals, nucleic acids, steroids and miscellaneous compounds of interest in biological research. Most methods of labelling employed lead to specific labelling, that is, to modecules in which the position(s) of the radioactive atom(s) is known with certainty. However, isotope exchange reactions which are especially useful for labelling molecules with tritium are often non-specific. The routine use of tritium nuclear magnetic resonance spectroscopy has resolved any uncertainties in the specificity of labelling with tritium. Examples are given illustrating the effectiveness of this valuable analytical technique. A review of the synthesis of radiolabelled compounds would not be complete without reference to the special properties of the labelled compounds themselves which affect their useful shelf-life, self-decomposition, purification and analysis; factors which all need to be clearly understood in order to use radiolabelled compounds with confidence in scientific research.     

Radiochemical studies on generator eluted113mIn chloride

^113mIn is milked out of a¹¹³Sn-^113mIn generator with dilute hydrochloric acid for use in nuclear medicine. The concentrations of the various impurities like Sn, Zr and their colloidal forms which may trap^113mIn activity have to be initially evaluated before releasing the generator for medicinal use. The authors have evaluated the purity of the^113mIn-chloride obtained from the generators in detail. The possibility of using a mixture of HCl and NaCl as an alternative eluent for^113mIn has also been investigated. It has been observed that this new eluent gives greater yields of^113mIn and renders the final manipulation of isotonicity of indium labelled compounds easy.     

Mössbauer and NMR characterization of tin octoate: Neat and residues in RTV foams

We have investigated hydrolysis and oxidation effects on tin octoate and on tin-octoate residues in RTV polysiloxane foams by means of Nuclear Magnetic Resonance (NMR) and Mössbauer spectroscopy (MS). ¹¹⁹Sn NMR showed the presence of various tin species whereas ¹¹⁹Sn MS detected the presence of two oxidation states: Sn(II) and Sn(IV). The relative abundance of Sn(IV) increased as both the tin octoate and the foam aged. Foams were also solvent extracted and no selective extraction of one tin oxidation state was observed; both oxidation states were detected. ¹³C NMR indicated that octanoic acid is present in the tin octoate and in the foams as a residue. MS data showed that aging treatments of the foams and of the neat catalyst have a great effect on the tin oxidation state. The two spectroscopic methods complement each other in following the effects of hydrolysis and oxidation.     

Mass-independent isotopic fractionation of tin in chemical exchange reaction using a crown ether

Tin isotopes were fractionated by the liquid-liquid extraction technique with a crown ether, dicyclohexano-18-crown-6. The isotopic ratios of ^mSn/¹²⁰Sn (m: 116, 117, 118, 119, 122 and 124) were measured by multi-collector inductively coupled plasma spectrometry (MC-ICP-MS) on a Nu Plasma 500 with a precision better than 0.05 permil amu⁻¹ on each isotopic ratio. Odd atomic mass isotopes (¹¹⁷Sn and ¹¹⁹Sn) showed depletions compared to the even atomic mass isotopes (¹¹⁶Sn, ¹¹⁸Sn, ¹²²Sn and ¹²⁴Sn). We show that this odd-even staggering property originates from the nuclear field shift effect. The contribution of the nuclear field shift effect to the observed isotope enrichment factor was estimated to be ∼35%.     

Biological aspects of new organotin(IV) compounds of 3-maleimidopropionic acid

Four new compounds of organic mono carboxylic acid, 3-maleimidopropionic acid; with Bu₂Sn(IV)²⁺, Ph₃Sn(IV)⁺ and Cychex₃Sn(IV)⁺ having ligand to metal ratio 1:2 and 1:1 were prepared. The spectrophotometric techniques used for structure determination like ¹H-, ¹³C- and ¹¹⁹Sn-NMR, FT IR and ^119mSn Mössbauer have demonstrated that the organotin(IV) moieties establish chemical bonding with the ligand through carboxylic oxygen atom. The percent CHN analyses and MS data also corroborates the spectroscopic results. During in vitro LD₅₀, anti-fungal, anti-bacterial and anti-yeast bioassays promising results were exhibited. In vitro anti-tumour activity assays against five human tumor cell lines, MCF-7 Breast cancer-EVSA-T Breast cancer-WiDr Colon cancer-IGROV Ovarian cancer-M226 Non small cell lung cancer and anti-inflammatory screenings furnished the significant toxicities of the title complexes. In addition the triorganotin(IV) complexes were comparatively less toxic than the diorganotin(IV) complexes.     

Synthesis of novel bioactive phthalimido-4-methyl pentanoateorganotin(IV) esters with spectroscopic investigation

The synthesis of monomer, dimer, tricyclohexyl- and triphenyl-tin(IV) complexes with phthalimido-4-methyl pentanoic acid (PMPA) are described and characterized by FT IR, CHN analyzer, ¹H, ¹³C ¹¹⁹Sn NMR and ^119mSn Mössbauer spectroscopic techniques. In vitro ED₅₀, anti-tumor (phytotoxic), anti-yeast, blood pressure and heart rate effect, and bactericidal, fungicidal as well as analgesic bioassays of complexes are also be carried out. The ligand (PMPA) shows excellent analgesic activity while the dimer exhibit strong biocidal and excellent anti-tumor behavior besides of tri-organotin(IV) complexes.     

Synthesis of radioactive tributyl[113Sn]tin of high specific activity for use in environmental fate studies

A method of synthesis of tributyl[¹¹³Sn]tin,­(n/C₄H₉)₃¹¹³Sn(IV), from commercially avail-­able inorganic ¹¹³Sn(IV) is presented. Inorganic tin is first extracted in diethyl ether and reacted with C₄H₉MgCl to produce tetrabutyltin, (C₄H₉)₄¹¹³Sn, which is then debutylated with HgCl₂. The resulting tributyl[¹¹³Sn]tin chloride is isolated from the reaction mixture by successive extractions with hexane and aqueous Na₂S₂O₃. The yield is 40–60% and the product obtained is >98% pure. It has the same specific activity as the starting ¹¹³Sn(IV), i.e. up to 550 MBq mg⁻¹ Sn, making it suitable for use in environmental fate and toxicology studies at concentrations relevant of those found in the aquatic environment. © 1998 John Wiley & Sons, Ltd.     

Studies on C-heterocyclic tin compounds. The synthesis and spectral characterization of some thienyl tetraorganotin(IV) compounds

The synthesis of a series of tetraorganotin(IV) compounds containing selectively the 2-thienyl, 3-thienyl, 5-methyl-2-thienyl, 5-t-butyl-2-thienyl, 4-methyl-2-thienyl and 3-(2-pyridyl)-2-thienyl groups [L], of formula R_4-nSn[L]_n (R = Ph, p-tolyl, Me, cyclopentyl, cyclohexyl; n = 1–4) is reported. Features of structural interest deduced from ^119mSn Mössbauer and NMR (¹³C and ¹¹⁹Sn modes) spectra are considered.     

Isotope exchange between 12-molybdocerate(IV) and sodium molybdate-99Mo in aqueous media

12-molybdocerate(IV) gel labelled with⁹⁹Mo has been prepared via isotope exchange between a column of inactive molybdate matrix and a mobile solution of⁹⁹-Mo-sodium molybdate(VI) in 0.1 mol·dm^–3 HNO₃. The composition and nature of the reaction mixture, concentration of Mo(VI) in the reactants, reaction temperature and/or drying temperature of the gel matrix on the exchange yeild of⁹⁹Mo and time of reaction are explored using the batch equilibration and/or the chromatographic column methods. The obtained material is evaluated for use in preparation of elution-type⁹⁹Mo-^99mTc generators.     

Subtoichiometric determination of indium and tin by radioactivation analysis

A method of radioactivation analysis has been developed for the determination of indium and tin. It is based on substoichiometric extraction of indium diethyldithiocarbamate into carbon tetrachloride from a slightly ammoniacal solution in the presence of potassium cyanide. With this method, indium can be determined via^116m In (T=54 min) and tin via^113m In (T=104 min) which is formed by the reaction¹¹²Sn(n, ψ)¹¹³Sn. The method has been applied to the determination of indium in metallic zinc and of tin in tin-doped gallium arsenide, and 0.4 ppb of indium was analyzed in a zinc sample.     

Separation of113mIn from113Sn on an isotope generator with inorganic ionite

A method of preparation of hydrated zirconium oxide suitable for^113mIn generators was elaborated. A good separation of^113mIn from¹¹³Sn was obtained in the course of routine use of generator, with a very small admixture of zirconium in the eluate.     

Electrochemical determination of Sn(IV)/Sn(II) ratio in tin sol formed in copper–tin sulphate solution containing laprol 2402C

The electrochemical method was applied to determine Sn(IV)/Sn(II) molar ratio in negatively charged colloid which forms in bronze plating sulphate solution containing laprol 2402C as a surface-active substance. An analysis of characteristic voltammetric minimum the onset of which is highly sensitive to Sn²⁺ concentration was used for this purpose. The Sn(IV)/Sn(II) ratio was found to be constant for completely formed colloid and independent on Cu(II) concentration in the solution. Particles involving Sn(IV) are supposed to be the main component responsible for stability of the sol.