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High-valent Ru V -oxo intermediates have long been proposed in catalytic oxidation chemistry, but investigations into their electronic and chemical properties have been limited due to their reactive nature and rarity. The incorporation of Ru into the [Co 3 O 4 ] subcluster via the single-step assembly reaction of Co II (OAc) 2 (H 2 O) 4 (OAc = acetate), perruthenate (RuO 4 - ), and pyridine (py) yielded an unprecedented Ru(O)Co 3 (μ 3 -O) 4 (OAc) 4 (py) 3 cubane featuring an isolable, yet reactive, Ru V -oxo moiety. EPR, ENDOR, and DFT studies reveal a valence-localized [Ru V ( S = 1/2)Co III 3 ( S = 0)O 4 ] configuration and non-negligible covalency in the cubane core. Significant oxyl radical character in the Ru V -oxo unit is experimentally demonstrated by radical coupling reactions between the oxo cubane and both 2,4,6-tri- tert -butylphenoxyl and trityl radicals. The oxo cubane oxidizes organic substrates and, notably, reacts with water to form an isolable μ-oxo bis-cubane complex [(py) 3 (OAc) 4 Co 3 (μ 3 -O) 4 Ru]-O-[RuCo 3 (μ 3 -O) 4 (OAc) 4 (py) 3 ]. Redox activity of the Ru V -oxo fragment is easily tuned by the electron-donating ability of the distal pyridyl ligand set at the Co sites demonstrating strong electronic communication throughout the entire cubane cluster. Natural bond orbital calculations reveal cooperative orbital interactions of the [Co 3 O 4 ] unit in supporting the Ru V -oxo moiety via a strong π-electron donation.

Introduction: The demand for Gallium-68 ( 68 Ga) for labelling PET radiopharmaceuticals has increased over the past few years. 68 Ga is obtained through the decayed parent radionuclide 68 Ge using commercial 68 Ge/ 68 Ga generators. The principal limitation of commercial 68 Ge/ 68 Ga generators is that only a limited and finite quantity of 68 Ga (<1.85 GBq at start of synthesis) may be accessed. The focus of this study was to investigate the use of a low energy medical cyclotron for the production of greater quantities of 68 Ga and to develop an automated and rapid procedure for processing the product., Methods: Enriched ZnCl 2 was electrodeposited on a platinum backing using a NH 4 Cl (pH 2-4) buffer. The Zn target was irradiated with GE PETtrace 880 at 35 μA and 14.5 and 12.0 MeV beam energy. The irradiated Zn target was purified using octanol resin on an automated system., Results: Following the described procedure, 68 Ga was obtained in 6.30 ± 0.42 GBq after 8.5 min bombardment and with low radionuclidic impurities ( 66 Ga (<0.005%) and 67 Ga (<0.09%)). Purification on a single octanol resin gave 82% recovery with resulting [ 68 Ga]GaCl 3 obtained in 3.5 mL of 0.2 M HCl. [ 68 Ga]GaCl 3 production from irradiation to final product was <45 min. To highlight the utility of the automated procedure, [ 68 Ga]Ga-DOTA-TATE labelling was incorporated to give 1.56 GBq at EOS of the labelled peptide with RCY of >70%., Conclusions: A straightforward procedure for producing 68 Ga on a low energy medical cyclotron was described. Current efforts are focus on high activity production and radiolabelling using solid target produced 68 Ga., (Crown Copyright © 2019. Published by Elsevier Inc. All rights reserved.)

Ion mobility-mass spectrometry (IM-MS) allows the separation of isomeric and isobaric species on the basis of their size, shape, and charge. The fast separation timescale (ms) and high sensitivity of these measurements make IM-MS an ideally suitable method for monitoring changes in macromolecular structure, such as those occurring in interconverting terpyridine-based metallosupramolecular self-assemblies. IM-MS is used to verify the elemental composition (size) and architecture (shape) of the self-assembled products. Additionally, this article demonstrates its applicability to the elucidation of concentration-driven association-dissociation (fusion-fission) equilibria between isobaric structures. IM-MS enables both quantitative separation and identification of the interconverting complexes as well as derivation of the corresponding equilibrium constants (i.e., thermodynamic information) from extracted IM-MS abundance data., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Gadolinium based contrast agents (GBCAs) have been linked to toxicity in patients, regardless of having impaired or normal renal function. Currently, no therapy is considered highly effective for removing gadolinium (Gd) from the body. We propose a new strategy to reduce blood Gd content that facilitates whole body removal of Gd using a hemoperfusion system consisting of a cartridge of porous silica beads (Davisil®) functionalized with 1,2-hydroxypyridinone (1,2-HOPO). Herein, we report optimization of the hemoperfusion system using an ex vivo blood and an in vivo rat model of chronic kidney disease (CKD). In our ex vivo system, 1,2-HOPO-Davisil outperformed Gambro activated charcoal (AC), which is commonly used in clinical hemoperfusion of aqueous toxins, in terms of Gd capture capacity and rate. In the CKD rat model, the 1,2-HOPO-Davisil hemoperfusion system removed Gd by 3.4 times over the Gambro AC system. 1,2-HOPO-Davisil did not change complete blood counts and common blood biochemistry. Thus, this strategy has great potential for clinical translation to manage GBCAs after magnetic resonance imaging (MRI), before Gd can deposit in the body and cause long-term toxicity. Although gadodiamide was used as a proof of concept model for GBCAs in this study, 1,2-HOPO functionalized mesoporous silica could also capture dissociated Gd and other GBCAs.

Background: In patients with renal failure, gadolinium-based contrast agents (GBCA) can be removed by intermittent hemodialysis (iHD) to prevent possible toxic effects. There is no data on the efficacy of GBCA removal via sustained low efficiency daily dialysis (SLEDD) which is mainly used in intensive care unit (ICU) patients., Methods: We compared the elimination of the GBCA gadobutrol in 6 ICU patients treated with SLEDD (6-12 h, 90 L dialysate) with 7 normal ward inpatients treated with iHD (4 h, dialysate flow 500 mL/min). Both groups received 3 dialysis sessions on 3 consecutive days starting after the application of gadobutrol. Blood samples were drawn before and after each session and total dialysate, as well as urine was collected. Gadolinium (Gd) concentrations were measured using mass spectrometry and eliminated Gd was calculated from dialysate and urine., Results: The initial mean plasma Gd concentration was 385 ± 183 µM for the iHD and 270 ± 97 µM for the SLEDD group, respectively (p > 0.05). The Gd-reduction rate after the first dialysis session was 83 ± 9 and 67 ± 9% for the iHD and the SLEDD groups, respectively (p = 0.0083). The Gd-reduction rate after the second and third dialysis was 94-98 and 89-96% for the iHD and the SLEDD groups (p > 0.05). The total eliminated Gd was 89 ± 14 and 91 ± 4% of the dose in the iHD and the SLEDD groups, respectively (p > 0.05). Gd dialyzer clearance was 95 ± 22 mL/min and 79 ± 19 mL/min for iHD and SLEDD, respectively (p > 0.05)., Conclusions: Gd-elimination with SLEDD is equally effective as iHD and can be safely used to remove GBCA in ICU patients., (© 2019 The Author(s) Published by S. Karger AG, Basel.)

Major Cinchona alkaloids quinine, quinidine, cinchonine, and cinchonidine are available chiral natural compounds (chiral pool). Unlike many other natural products, these alkaloids are available in multiple diastereomeric forms which are separated on an industrial scale. The introduction discusses in short conformational equilibria, traditional separation scheme, biosynthesis, and de novo chemical syntheses. The second section concerns useful chemical applications of the alkaloids as chiral recognition agents and effective chiral catalysts. Besides the Sharpless ethers and quaternary ammonium salts (chiral PTC), the most successful bifunctional organocatalysts are based on 9-amino derivatives: thioureas and squaramides. The third section reports the main transformations of Cinchona alkaloids. This covers reactions of the 9-hydroxyl group with the retention or inversion of configuration. Specific Cinchona rearrangements enlarging [2.2.2]bicycle of quinuclidine to [3.2.2] products are connected to the 9-OH substitution. The syntheses of numerous esterification and etherification products are described, including many examples of bi-Cinchona alkaloid ethers. Further derivatives comprise 9-N-substituted compounds. The amino group is introduced via an azido function with the inversion of configuration at the stereogenic center C9. The 9-epi-amino-alkaloids provide imines, amides, imides, thioureas, and squaramides. The syntheses of 9-carbon-, 9-sulfur-, and 9-selenium-substituted derivatives are discussed. Oxidation of the hydroxyl group of any alkaloid gives ketones, which can be selectively reduced, reacted with Grignard reagents, or subjected to the Corey-Chaykovsky reaction. The alkaloids were also partially degraded by splitting C4'-C9 or N1-C8 bonds. In order to immobilize Cinchona alkaloids the transformations of the 3-vinyl group were often exploited. Finally, miscellaneous functionalizations of quinuclidine, quinoline, and examples of various metal complexes of the alkaloids are considered., (© 2019 Elsevier Inc. All rights reserved.)

The objective of this study was to develop instant thin-layer chromatography (ITLC) conditions for the determination of radiochemical purity of 68 Ga-DOTATATE in a shorter time period than those stated in the NETSPOT (Advanced Accelerator Applications, Saint-Genis-Pouilly, France; AAA) kit package insert (PI). A faster ITLC system is needed to reduce the 48- to 50-min development time so that more radioactivity is available for single patient use and wait times are shorter in the event of kit failure. Methods: Variations of the PI mobile system were evaluated with microfiber chromatography paper impregnated with silica gel (ITLC-SG). After a more suitable mobile system was identified, evaluation began by attempting to shorten the 10-cm development distance to 7, 8, and 9 cm. Results: Experiments using variations of PI mobile phase showed that increasing the proportion of methanol in the mobile phase decreased development time. Additionally, if the ratio of 1 M ammonium acetate was reduced to 10% or less, retention factor values fall outside specification. Reducing the development distance shortened development time as expected; however, it also affected the resolution aspect of the radiochromatogram. Conclusion: The fastest developing ITLC system, which maintained resolution and peak shape, was methanol:1 M ammonium acetate (80:20 V/V) with ITLC-SG using a development distance of 8 cm., (© 2018 by the Society of Nuclear Medicine and Molecular Imaging.)

Background: There are many calcium supplements available in the market, especially those containing calcium in the form of carbonate, which unfortunately is not absorbed by the body to a sufficient degree., Method: Therefore, an attempt was made to prepare new sources of calcium, consuming the chicken eggshells as natural raw materials, which were used in preparation of tablets containing calcium carbonate and calcium citrate as well as tablets with calcium carbonate and calcium bisglycinate. The influence of raw material properties on the pharmaceutical availability of calcium from the obtained tablets was investigated., Results: Based on the obtained calcium release profiles from the prepared tablets, it was found that the optimal source of calcium is a preparation containing calcium from chicken eggshells. It was found that both chicken eggshells and calcium bisglycinate (chelate) may be new, prospective sources of calcium. Calcium citrate prepared using eggshells as starting materials and bisglycinate is completely released within no more than 150 minutes., Conclusion: In turn, calcium carbonate added to calcium bisglycinate statistically significantly prolonges the release of calcium ions to 4 hours., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

The baseline separation of divinylbenzene (DVB) and ethylvinylbenzene (EVB) isomers was achieved using HPLC with MIL-53(Fe) and MIL-100(Fe) packed columns respectively when hexane/dichloromethane (100:0) used as mobile phase, at flow rate of 0.5mLmin -1 , room temperature, and monitored with a UV detector at 254nm. The two Fe-based MILs packed columns showed different separated performances, analytes had short retention time on MIL-100(Fe) compared to MIL-53(Fe), but selectivity of DVB isomers (m-DVB and p-DVB) was lower, which was mainly due to the differences of the pore size and structure of MILs. Moreover, the results of calculated thermodynamic parameters showed that the separation of DVB and EVB isomers was not only controlled by enthalpy change (ΔH), but also controlled by entropy change (ΔS). The head-to-tail stacking was the main reason for the separation according to the mechanism of the DVB and EVB isomers on Fe-based MILs packed columns., (Copyright © 2017. Published by Elsevier B.V.)

The characterization of intermediates formed through the reaction of transition-metal complexes with dioxygen (O 2 ) is important for understanding oxidation in biological and synthetic processes. Here, the reaction of the diketiminate-supported cobalt(I) complex L tBu Co with O 2 gives a rare example of a side-on dioxygen complex of cobalt. Structural, spectroscopic, and computational data are most consistent with its assignment as a cobalt(III)-peroxo complex. Treatment of L tBu Co(O 2 ) with low-valent Fe and Co diketiminate complexes affords isolable oxo species with M 2 O 2 "diamond" cores, including the first example of a crystallographically characterized heterobimetallic bis(μ-oxo) complex of two transition metals. The bimetallic species are capable of cleaving C-H bonds in the supporting ligands, and kinetic studies show that the Fe/Co heterobimetallic species activates C-H bonds much more rapidly than the Co/Co homobimetallic analogue. Thus heterobimetallic oxo intermediates provide a promising route for enhancing the rates of oxidation reactions., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Supercritical fluid extraction (SFE), as a new green extraction technology, has been used in extracting various metal species. The solubilities of chelating agents and corresponding metal chelates are the key factors which influence the efficiency of SFE. Other main properties of them such as stability and selectivity are also reviewed. The extraction mechanisms of mainly used chelating agents are explained by typical examples in this paper. This is the important aspect of SFE of metal ions. Moreover, the extraction efficiencies of metal species also depend on other factors such as temperature, pressure, extraction time and matrix effect. The two main complexation methods namely in-situ and on-line chelating SFE are described in detail. As an efficient chelating agent, tributyl phosphate-nitric acid (TBP-HNO 3 ) complex attracts much attention. The SFE of metal ions, lanthanides and actinides as well as organometallic compounds are also summarized. With the proper selection of ligands, high efficient extraction of metal species can be obtained. As an efficient sample analysis method, supercritical fluid chromatography (SFC) is introduced in this paper. Recently, the extraction method combining ionic liquids (ILs) with supercritical fluid has been becoming a novel technology for treating metal ions. The kinetics related to SFE of metal species is discussed with some specific examples.

Yttrium-90 obtained from most of the 90 Sr/ 90 Y generators contains 90 Sr impurity above permissible limit for human administration. A protocol has been optimized for formulation of therapeutic dose of 90 Y-DOTA-Tyr 3 -octreotate ( 90 Y-DOTA-TATE) and removal of 90 Sr impurity from it. The radiochemical purity of 90 Y-DOTA-TATE was found to be >98% and it met the requirements for clinical use. The radiopharmaceutical was used in preliminary clinical investigation in patients with neuroendocrine tumors. This promising strategy would aid toward widespread clinical utilization of 90 Sr/ 90 Y generators., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Tricholoma matsutake, a basidiomycete, forms ectomycorrhizas with Pinus densiflora as the host tree. Its fruiting body, "matsutake" in Japanese, is an edible and highly prized mushroom, and it grows in a circle called a fairy ring. Beneath the fairy ring of T. matsutake, a whitish mycelium-soil aggregated zone, called "shiro" in Japanese, develops. The front of the shiro, an active mycorrhizal zone, functions to gather nutrients from the soil and roots to nourish the fairy ring. Bacteria and sporulating fungi decrease from the shiro front, whereas they increase inside and outside the shiro front. Ohara demonstrated that the shiro front exhibited antimicrobial activity, but the antimicrobial substance has remained unidentified for 50 years. We have identified the antimicrobial substance as the (oxalato)aluminate complex, known as a reaction product of oxalic acid and aluminum phosphate to release soluble phosphorus. The complex protects the shiro from micro-organisms, and contributes to its development.

Enzymatic processes have great potential for applications in industrial biocatalysis, biosensing, and biomedical engineering. However, poor stability and difficulty in the reuse of enzymes still create challenges for their use in catalysis and other applications. In recent years, enzyme-incorporated metal-organic frameworks (enzyme@MOF) have emerged as a new type of armored enzymes and are thought to be an appealing solution to the above challenges. To date, the preparation of enzyme-MOF composites can be divided into three categories, including physical adsorption, covalent conjugation, and coprecipitation. The coprecipitation method integrates the synthesis of MOFs and encapsulation of enzymes into one step, allowing common MOFs with regular pore sizes to be used as carriers for enzyme binding. In this chapter, we present a protocol for the synthesis of enzyme@MOF composites using the coprecipitation approach with particular details., (© 2017 Elsevier Inc. All rights reserved.)

An efficient (+)-camphor-mediated kinetic resolution of racemic cyclohex-2-en-1-ylalane is described. This approach provides an enantiomerically enriched form of the alane, in situ available for synthetic uses. Applied to the allylation of aldehydes, this protocol leads to the corresponding homoallylalcohols in a highly enantioselective manner.

A racemic mixture of a new chiral Schiff base ligand (HL: R/S-(1-phenylethylimino)methylnaphtalen-2-ol) has been utilized to prepare Pd(II) complex. Crystallization technique has been employed to separate diastereomeric pairs of Pd(II) complex: (mesoPdL2) and (racPdL2) that in this paper are known as PdL2(1) and PdL2(2), respectively. The synthesized complexes have been characterized by means of elemental analysis (CHN), FT-IR, (1)H and (13)C NMR spectroscopies. Moreover, PdL2(1) has been structurally characterized by single-crystal X-ray diffraction. The geometry around the metal center is square-planar. The interaction of two diastereomers of Pd(II) complex with FS-DNA has been explored, using UV-vis spectroscopy, fluorescence quenching, chemometrics and viscosity measurement methods. The PdL2(1) exhibited higher binding constant, about 10-fold, (1.0×10(6)M(-1)) as compared to PdL2(2) (1.51.5×10(5)M(-1)). Moreover, the human serum albumin (HSA) binding ability has been monitored by absorption, quenching of tryptophan fluorescence emission and circular dichroism (CD) studies. The slight difference is observed between HSA binding affinity with the complexes: PdL2(1) (6.2×10(4)M(-1)) and PdL2(2) (3.3×10(4)M(-1)). Also, the thermodynamic parameters were determined at three different temperatures (298, 308 and 318K). In this study, molecular docking was also carried out to confirm and illustrate the specific DNA- and HSA-binding of the Pd(II) complexes. In the PdL2(1)-HSA system a T-shaped π-π interaction with PHE206 was observed. While in the PdL2(2)-HSA system there are a hydrogen bond, a π-cation and two T-shaped π-π interactions with ASB324, LYS212 and PHE228, respectively. The groove binding mode of DNA interaction has been proposed for both diastereomers., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Due to insufficient information, the aim of study was to concern on the optimization of extraction procedure of selected metal complexes with flavonoids from chia seeds. Evaluation of the amount of elements in compound, not only their total concentration content, is highly important due to the fact, that only a part from total content of metal is absorbed by human body. At the beginning the total amount of elements in chia seeds was established as 14.51±0.42 µg g(-1) for copper, 57.44±1.23 µg g(-1) for manganese, 81.12±1.89 µg g(-1) for zinc and 0.35±0.13 µg g(-1) for cobalt. After the most suitable solvent was established, effects of several parameters on the efficiency of metal extraction were studied. Solvent concentration, solid-solvent ratio, extraction method, extraction time and temperature have been investigated as independent variables. The optimal extraction conditions included vortexing during 20 min in 50°C, using an ionic liquid (1-butyl-3-methylimidazolium bromide) as an extractant, with solid-solvent ratio of 1:20. The determination of total and extractable amount of metals in chia seeds was carried out by standalone ICP MS. In addition, a complementary analysis of extracted metal complexes was performed using SEC-ICP MS method. It was confirmed that the ionic liquid is able to extract different copper complexes in comparison with commonly used solvents. The study indicated that extraction by using an ionic liquid has been successfully applied for determination of metals and metal complexes in chia seeds., (Copyright © 2016 Elsevier B.V. All rights reserved.)

(68)Ga-DOTA-peptides are a promising PET radiotracers used in the detection of different tumours types due to their ability for binding specifically receptors overexpressed in these. Furthermore, (68)Ga can be produced by a (68)Ge/(68)Ga generator on site which is a very good alternative to cyclotron-based PET isotopes. Here, we describe a manual labelling approach for the synthesis of (68)Ga-labelled DOTA-peptides based on concentration and purification of the commercial (68)Ga/(68)Ga generator eluate using an anion exchange-cartridge. (68)Ga-DOTA-TATE was used to image a pheochromocytoma xenograft mouse model by a microPET/CT scanner. The method described provides satisfactory results, allowing the subsequent (68)Ga use to label DOTA-peptides. The simplicity of the method along with its implementation reduced cost, makes it useful in preclinical PET studies., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Capillary electrophoresis has recently attracted considerable attention as a promising analytical technique for metal ion separations. Significant advances that open new application areas for capillary electrophoresis in the analysis of metal species occurred based on various auxiliary separation principles. These are mainly due to complexation, ion pairing, solvation, and micellization interactions between metal analytes and electrolyte additives, which alter the separation selectivity in a broad range. Likewise, many separation studies for metal ions have been concentrated on the use of preelectrophoresis derivatization methodology. Approaches suitable for manipulation of selectivity for different metal species including metal cations, metal complexes, metal oxoanions, and organometallic compounds, are discussed, with special attention paid to the related electrophoretic system variables using illustrative examples.

Reaction of Tp(iPr)Mo(VI)OS(OAr) with cobaltocene in toluene results in the precipitation of brown, microcrystalline oxosulfido-Mo(V) compounds, [CoCp2][Tp(iPr)Mo(V)OS(OAr)] (Cp(-) = η(5)-C5H5(-), Tp(iPr)(-) = hydrotris(3-isopropylpyrazol-1-yl)borate, OAr(-) = phenolate or 2-(s)Bu, 2-(t)Bu, 3-(t)Bu, 4-(s)Bu, 4-Ph, 3,5-(s)Bu2, 2-CO2Me, 2-CO2Et or 2-CO2Ph derivative thereof). The compounds are air- and water-sensitive and display ν(Mo═O) and ν(Mo[Formula: see text]S) IR absorption bands at ca. 890 and 435 cm(-1), respectively, 20-40 cm(-1) lower in energy than the corresponding bands in Tp(iPr)MoOS(OAr). They are electrochemically active and exhibit three reversible cyclovoltammetric waves (E(Mo(VI)/Mo(V)) = -0.40 to -0.66 V, E([CoCp2](+)/CoCp2) = -0.94 V and E(CoCp2/[CoCp2](-)) = -1.88 V vs SCE). Structural characterization of [CoCp2][Tp(iPr)MoOS(OC6H4CO2Et-2)]·2CH2Cl2 revealed a distorted octahedral Mo(V) anion with Mo═O and Mo[Formula: see text]S distances of 1.761(5) and 2.215(2) Å, respectively, longer than corresponding distances in related Tp(iPr)MoOS(OAr) compounds. The observation of strong S(1s) → (S(3p) + Mo(4d)) S K-preedge transitions indicative of a d(1) sulfido-Mo(V) moiety and the presence of short Mo═O (ca. 1.72 Å) and Mo[Formula: see text]S (ca. 2.25 Å) backscattering contributions in the Mo K-edge EXAFS further support the oxosulfido-Mo(V) formulation. The compounds are EPR-active, exhibiting highly anisotropic (Δg 0.124-0.150), rhombic, frozen-glass spectra with g1 close to the value observed for the free electron (ge = 2.0023). Spectroscopic studies are consistent with the presence of a highly covalent Mo[Formula: see text]S π* singly occupied molecular orbital. The compounds are highly reactive, with reactions localized at the terminal sulfido ligand. For example, the compounds react with cyanide and PPh3 to produce thiocyanate and SPPh3, respectively, and various (depending on solvent) oxo-Mo(V) species. Reactions with copper reagents also generally lead to desulfurization and the formation of oxo-Mo(V) or -Mo(IV) complexes.

The complexation of U(vi) at the proteinaceous surface layer (S-layer) of the archaeal strain Sulfolobus acidocaldarius was investigated over a pH range from pH 1.5 to 6 at the molecular scale using time-resolved laser-induced fluorescence spectroscopy (TRLFS) and U L(III)-edge extended X-ray absorption fine structure (EXAFS). The S-layer, which represents the interface between the cell and its environment, is very stable against high temperatures, proteases, and detergents. This allowed the isolation and purification of S-layer ghosts (= empty cells) that maintain the size and shape of the cells. In contrast to many other microbial cell envelope compounds the studied S-layer is not phosphorylated, enabling the investigation of uranyl carboxylate complexes formed at microbial surfaces. The latter are usually masked by preferentially formed uranyl phosphate complexes. We demonstrated that at highly acidic conditions (pH 1.5 to 3) no uranium was bound by the S-layer. In contrast to that, at moderate acidic pH conditions (pH 4.5 and 6) a complexation of U(vi) at the S-layer via deprotonated carboxylic groups was stimulated. Titration studies revealed dissociation constants for the carboxylic groups of glutamic and aspartic acid residues of pK(a) = 4.78 and 6.31. The uranyl carboxylate complexes formed at the S-layer did not show luminescence properties at room temperature, but only under cryogenic conditions. The obtained luminescence maxima are similar to those of uranyl acetate. EXAFS spectroscopy demonstrated that U(vi) in these complexes is mainly coordinated to carboxylate groups in a bidentate binding mode. The elucidation of the molecular structure of these complexes was facilitated by the absence of phosphate groups in the studied S-layer protein.

Metals are a key component of many diagnostic imaging and biotechnology applications, and the majority of cancer patients receive a platinum-based drug as part of their treatment. Significant effort has been devoted to developing tight binding synthetic chelators to enable effective targeted delivery of metal-based conjugates, with most successes involving lanthanides rather than transition metals for diagnostic imaging. Chemical conjugation modifies the protein's properties and generates a heterogeneous mixture of products. Chelator attachment is typically carried out by converting the amino group on lysines to an amide, which can impact the stability and solubility of the targeting protein and these properties vary among the set of individual conjugate species. Site-specific attachment is sought to reduce complexity and control stability. Here, the metal abstraction peptide technology was applied to create the claMP Tag, an inline platform for generating site-specific conjugates involving transition metals. The claMP Tag was genetically encoded into epidermal growth factor (EGF) and loaded with nickel(II) as a model system to demonstrate that the tag within the homogeneous inline conjugate presents sufficient solution stability to enable biotechnology applications. The structure and disulfide network of the protein and chemical stability of the claMP Tag and EGF components were characterized., (© 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.)

Tellurium-containing phycocyanin (Te-PC) and allophycocyanin (Te-APC), two organic tellurium (Te) species, were purified from tellurium-enriched Spirulina platensis by a fast protein liquid chromatographic method. It was found that the incorporation of Te into the peptides enhanced the antioxidant activities of both phycobiliproteins. With fractionation by ammonium sulfate precipitation and hydroxylapatite chromatography, Te-PC and Te-APC could be effectively separated with high purity, and Te concentrations were 611.1 and 625.3 μg g(-1) protein in Te-PC and Te-APC, respectively. The subunits in the proteins were identified by using MALDI-TOF-TOF mass spectrometry. Te incorporation enhanced the antioxidant activities of both phycobiliproteins, as examined by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid assay. Moreover, Te-PC and Te-APC showed dose-dependent protection on erythrocytes against the water-soluble free radical initiator 2,2'-azo(2-asmidinopropane)dihydrochloride-induced hemolysis. In the hepatoprotective model, apoptotic cell death and nuclear condensation induced by tert-butyl hydroperoxide in HepG2 cells was significantly attenuated by Te-PC and Te-APC. Taken together, these results suggest that Te-PC and Te-APC are promising Te-containing proteins with application potential for treatment of diseases related to oxidative stress.

Gadolinium complexed with naturally occurring, negatively charged humic substances (humic and fulvic acids) was collected from 500 mL of sample solution onto a column packed with 150 mg of a strongly basic anion-exchanger (QAE-Sephadex A-25). A Gd-based magnetic resonance imaging contrast agent (diethylenetriamine-N,N,N',N″,N″-pentaacetato aquo gadolinium(III), Gd-DTPA(2-)) was simultaneously collected on the same column. The Gd-DTPA complex was desorbed by anion-exchange with 50mM tetramethylammonium sulfate, leaving the Gd-humic complexes on the column. The Gd-humic complexes were subsequently dissociated with 1M nitric acid to desorb the humic fraction of Gd. The two-step desorption with small volumes of the eluting agents allowed the 100-fold preconcentration for the fractionation analysis of Gd at low ng L(-1) levels by inductively coupled plasma-mass spectrometry (ICP-MS). On the other hand, Gd(III) neither complexed with humic substances nor DTPA, i.e., free species, was not sorbed on the column. The free Gd in the effluent was preconcentrated 100-fold by a conventional solid-phase extraction with an iminodiacetic acid-type chelating resin and determined by ICP-MS. The proposed analytical fractionation method was applied to river water samples., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Metallic nanoparticles are major concern, particularly silver nanoparticles (AgNPs) are used in various applications. In the present investigation, we report a novel strategy with biological approach for synthesis of AgNPs using sodium para-hydroxybenzoate tetrahydrate (SPHT) isolated from Vitex negundo leaves. The synthesized SPHT-AgNPs were characterized by UV-vis spectroscopy, high resolution transmission electron microscopy (HRTEM) with selected area electron diffraction (SAED) pattern, field emission scanning electron microscopy (FESEM) with energy-dispersive X-ray spectroscopy (EDX), zeta potential and Fourier transform infrared spectroscopy (FT-IR) analysis. The various pH and temperature were evaluated to find their stability effects on SPHT-AgNPs synthesis peak at 430 nm. The size of SPHT-AgNPs were ranging from 26 to 39 nm and were spherical in shape. The hydroxyl and carboxylic functional groups from bio-reducing mediators of SPHT have a stronger ability towards synthesis of AgNPs, which was confirmed using FT-IR spectrum. In addition, anticancer activity were determined by MTT assay, Annexin V-FITC/PI and cell cycle analysis., (Copyright © 2014 Elsevier Masson SAS. All rights reserved.)

The Gliding Arc Discharge (GAD) is an efficient non-thermal plasma technique able to degrade organic compounds dispersed in water at atmospheric pressure. The degradation of the organometallic lead acetate (PbAc) in aqueous solution was performed by two distinct plasmageneous processes: GAD and GAD/TiO2. The global oxidation of the organic matter was followed by Chemical Oxygen Demand (COD) and the mineralization was determined by the Total Organic Carbon (TOC). The Pb(2+) ions released during the degradation process were measured by Atomic Absorption Spectroscopy (AAS). For 2h of GAD treatment, the degradation rate of PbAc (10mM) reached 83% and for the same duration of GAD/TiO2 process ([TiO2]=1gL(-1)), it reached 93%. The release of Pb(2+) ions in the solution was respectively of 95% and 57% for GAD and GAD/TiO2 processes. The released Pb(2+) ions were removed by precipitation process in a basic medium at pH=11.1. A reaction mechanism was proposed to explain the PbAc molecule degradation and the Pb(2+) elimination., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Here we report the synthesis and isolation of a series of bis-chelate Cu(2+) phenanthroline-phenazine cationic complexes of [Cu(DPQ)(Phen)](2+), [Cu(DPPZ)(Phen)](2+), and [Cu(DPPN)(Phen)](2+) (where Phen = 1,10-phenanthroline, DPQ = dipyridoquinoxaline, DPPZ = dipyridophenazine, and DPPN = benzo[i]dipyridophenazine). These compounds have enhanced DNA recognition relative to the well-studied chemical nuclease, [Cu(Phen)2](2+) (bis-Phen), with calf thymus DNA binding constants of DPQ and DPPZ agents (∼10(7) M(bp)(-1)) being the highest currently known for Cu(2+) phenanthrene compounds. Complex DNA binding follows DPQ ≈ DPPZ > DPPN > bis-Phen, with fluorescence quenching and thermal melting experiments on poly[d(A-T)2] and poly[d(G-C)2] supporting intercalation at both the minor and major groove. Phenazine complexes, however, show enhanced targeting and oxidative cleavage on cytosine-phosphate-guanine-rich DNA and have comparable in vitro cytotoxicity toward the cisplatin-resistant ovarian cancer line, SKOV3, as the clinical oxidative DNA-damaging drug doxorubicin (Adriamycin). In this study we also describe how a novel "on-chip" method devised for the Bioanalyser 2100 was employed to quantify double-stranded DNA damage, with high precision, by the complex series on pUC19 DNA (49% A-T, 51% G-C). Both DPQ and bis-Phen complexes are highly efficient oxidizers of pUC19, with DPQ being the most active of the overall series. It is apparent, therefore, that oxidative chemical nuclease activity on homogeneous canonical DNA is not entirely dependent on dynamic nucleotide binding affinity or intercalation, and this observation is corroborated through catalytic interactions with the superoxide anion radical and Fenton breakdown of hydrogen peroxide.

A versatile and straightforward synthetic approach is described for the preparation of triamide bearing analogues of sarcophagine hexaazamacrobicyclic cage ligands without the need for a templating metal ion. Reaction of 1,1,1-tris(aminoethyl)ethane (tame) with 3 equiv of 2-chloroacetyl chloride, yields the tris(α-chloroamide) synthetic intermediate 6, which when treated with either 1,1,1-tris(aminoethyl)ethane or 1,4,7-triazacyclononane furnished two novel triamidetriamine cryptand ligands (7 and 8 respectively). The Co(III) and Cu(II) complexes of cryptand 7 were prepared; however, cryptand 8 could not be metalated. The cryptands and the Co(III) complex 9 have been characterized by elemental analysis, (1)H and (13)C NMR spectroscopy, and X-ray crystallography. These studies confirm that the Co(III) complex 9 adopts an octahedral geometry with three facial deprotonated amido-donors and three facial amine donor groups. The Cu(II) complex 10 was characterized by elemental analysis, single crystal X-ray crystallography, cyclic voltammetry, and UV-visible absorption spectroscopy. In contrast to the Co(III) complex (9), the Cu(II) center adopts a square planar coordination geometry, with two amine and two deprotonated amido donor groups. Compound 10 exhibited a quasi-reversible, one-electron oxidation, which is assigned to the Cu(2+/3+) redox couple. These cryptands represent interesting ligands for radiopharmaceutical applications, and 7 has been labeled with (64)Cu to give (64)Cu-10. This complex showed good stability when subjected to L-cysteine challenge whereas low levels of decomplexation were evident in the presence of L-histidine.

Fused aryl phenazine derivatives (benzo[a]phenazine, pyrido[a]phenazine, benzo[a]phenazine diones, tetrahydropyrido[a]phenazine (dermacozines), etc) are important heterocyclic compounds, which exhibit various pharmacological activities, prominently in cancer cell lines. These compounds significantly intercalate between DNA base pairs and inhibit the activities of topoisomerase I and II enzymes (Topo I and II). XR11576, XR5944, NC-190 and NC-182 belong to phenazine/fused aryl phenazine category and are under clinical studies. Several fused aryl phenazine dione compounds such as pyridazino[4,5-b]phenazine-5,12-diones, 6,11-dihydro-pyrido[2,3-b]phenazine-6,11-diones, 6,11-dihydrobenzo[2,3-b]phenazine-6,11-diones, tetrahydropyrido[a]phenazine, etc possessed anticancer activities on various cancer cell lines. Benzo[a]phenazine diimine and various other fused aryl phenazine compounds form coordination complex with the metal ions (Ru, Rh, Zn and Pt) that intercalate with the DNA and are used for the treatment of cancer. These molecules have influence on MDR cancer cells and serve as anticancer agents in MDR cancer cells. The structure activity relationship of the fused aryl phenazine derivatives revealed that the occurrence of four or more nitrogen atoms in the compounds has better anticancer activity than those molecules with less number of nitrogen atoms. Phenazine antibiotics derived from marine microbes are used for the treatment of microbial and worm diseases. Recent patents on these scaffolds showed that the benzo[a]phenazine derivatives have inhibitory activity on topoisomerase enzymes (Topo I and II) and that act as anticancer agents.

Heteroaromatic secondary alcohols react with isoprene to form products of hydrohydroxyalkylation in the presence of ruthenium(0) catalysts generated from Ru3(CO)12 and tricyclohexylphosphine, enabling direct conversion of secondary to tertiary alcohols in the absence of premetalated reagents or stoichiometric byproducts. The putative oxaruthenacycle intermediate has been isolated and characterized, and reversible metallacycle formation has been demonstrated.

The identification of the ligands binding Al is essential to understand the mechanisms by which plants detoxify Al internally. However, studies concerning the speciation of Al have been frustrated by its complex chemistry. This work describes the identification of the tri-Al tricitrate (Al3cit3) complex in Plantago almogravensis, encompassing an integrated mass spectrometry approach based on hydrophilic interaction liquid chromatography (HILIC) and parallel detection by ICP-MS and ESI-MS/MS. This work also reports that both Al and Fe are bound by tricitrate, sometimes simultaneously, and the consequences of this finding are discussed. Of the complexes separated by size exclusion chromatography, Al3cit3 is the most stable occurring in P. almogravensis as it was the only one recovered after HILIC. This approach provided new information on the mechanism of Al detoxification in P. almogravensis, namely that Al is bound by the organic acid citrate and that the relative concentration of the detected complexes is affected by the organ type and internal Al concentration, and has potential for studying the speciation of Al in less tolerant plants.

Pentafluoroethane, C2F5H (HFC-125), is smoothly cuprated with preisolated or in situ-generated [K(DMF)][(t-BuO)2Cu] to give [K(DMF)2][(t-BuO)Cu(C2F5)] (1) in nearly quantitative yield. Complex 1 has been isolated, structurally characterized, and demonstrated to be an exceedingly versatile pentafluoroethylating reagent for a variety of substrates, including unactivated aryl bromides.

A complex of a binucleating macrocyclic ligand comprising a [Cu(II)(μ-OH)Na](2+) core reacts with CuI in THF/CH3CN to yield a novel species with a deprotonated 2-hydroxytetrahydrofuran (THF-2-ol) bridging between Cu(II) and Na(I) ions. The complexes were characterized by X-ray crystallography, electron paramagnetic resonance spectroscopy, and electrospray ionization mass spectrometry. (18)O-labeling studies support incorporation of the O atom from μ-OH into the coordinated THF-2-ol ligand.

In the course of the establishment of (68)Ga-DOTA-TATE production for clinical use a shoulder comprising presumably several impurities was observed in the chromatogram of the analytical radio-HPLC. LC-MS/MS results support the hypothesis that some of these radioimpurities are radiolytic oxidation by-products of (68)Ga-DOTA-TATE. A new HPLC method was developed for quality control of (68)Ga-DOTA-TATE. Significant improvement on the radiochemical purity of (68)Ga-DOTA-TATE was achieved by the addition of ascorbic acid or ethanol to the reaction mixture., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

σ-Alkyl iridium hydride complexes are generally postulated as intermediates in iridium-catalyzed hydrogenation. Fast reductive elimination results in the formation of the hydrogenation product. With an β-enamido ketone as unsaturated substrate, such an intermediate could be trapped because the semihydrogenated product coordinates trifold to the iridium, generating a stable 18e(-) complex, which does not eliminate.

The aim of the present study was to investigate the binding strength of chromium (Cr) ions to aquatic macrophyte Callitriche cophocarpa. Shoots of the plants were incubated in a natural water solution containing Cr(III) or Cr(VI) at a concentration ranging from 0.5 to 4 mM under laboratory conditions. We found that C. cophocarpa has an extremely high capacity to bind Cr. The average level of accumulation reached 28,385 or 7,315 mg kg(-1) dry weight for plants incubated with Cr(III) or Cr(VI), respectively. Shoots incubated in a 0.5 mM concentration of Cr(III) for 5 days removed almost 100 % of the metal from solution. The major pool of the bound Cr(III) ions follows the strongest mechanism of metal-binding to an organic matter. In contrast, we found that only 25 % of Cr(VI) ions are bound into the metallo-organic compounds and 57 % of Cr(VI) exists in an easily remobilizable form. Activity of a photosynthetic electron transport (as F V/F M) was evaluated with respect to the Cr-binding mechanism. Our results contribute to the development of knowledge on processes controlling bioremediation of heavy-metallic compounds in aquatic systems.

A molecular simulation study is reported to investigate liquid chromatographic separation in metal-organic framework MIL-101. Two mixtures are considered: three amino acids (Arg, Phe, and Trp) in aqueous solution and three xylene isomers (p-, m-, and o-xylene) dissolved in hexane. For the first mixture, the elution order is found to be Arg > Phe > Trp. The hydrophilic Arg has the strongest interaction with the polar mobile phase (water) and the weakest interaction with the stationary phase (MIL-101), and thus transports at the fastest velocity. Furthermore, Arg forms the largest number of hydrogen bonds with water and possesses the largest hydrophilic solvent-accessible surface area. For the second mixture, the elution order is p-xylene > m-xylene > o-xylene, consistent with available experimental observation. With the largest polarity as compared to p- and m-xylenes, o-xylene interacts the most strongly with the stationary phase and exhibits the slowest transport velocity. For both mixtures, the underlying separation mechanism is elucidated from detailed energetic and structural analysis. It is revealed that the separation can be attributed to the cooperative solute-solvent and solute-framework interactions. This simulation study, for the first time, provides molecular insight into liquid chromatographic separation in a MOF and suggests that MIL-101 might be an interesting material for the separation of industrially important liquid mixtures.

Cationic copper(I) dicarbonyl complexes supported by N-heterocyclic carbene ligands, SIPr and IPr*, have been synthesized. [(SIPr)Cu(CO)(2)][SbF(6)] and [(IPr*)Cu(CO)(2)][SbF(6)] have a trigonal planar, three-coordinate copper atom with an average Cu-CO distance of 1.915 Å and display C-O stretching frequencies higher than that of the free CO (2143 cm(-1)). The high CO stretching frequencies suggest that the Cu(I)-CO interaction in these cationic adducts is dominated by electrostatic and OC → Cu σ-donor components. [(SIPr)Cu(CO)(2)][SbF(6)] and [(IPr*)Cu(CO)(2)][SbF(6)] readily form the corresponding [(SIPr)Cu(CO)(H(2)O)][SbF(6)] and [(IPr*)Cu(CO)(H(2)O)][SbF(6)] with loss of a CO even with traces of water, but they can be converted back to the dicarbonyl adducts using excess CO. The synthesis and structure of [(IPr*)Cu(H(2)O)][SbF(6)] are also reported. It is a two-coordinate copper adduct with a Cu-O distance of 1.874(2) Å. It reacts with excess CO to form [(IPr*)Cu(CO)(2)][SbF(6)].

Hydrophilic interaction chromatography (HILIC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) was optimized for speciation analysis of gadolinium-based contrast agents in environmental samples, in particular surface river waters and plants. Surface water samples from the Teltow channel, near Berlin, were investigated over a distance of 5 km downstream from the influx of a wastewater treatment plant. The total concentration of gadolinium increased significantly from 50 to 990 ng L(-1) due to the influx of the contrast agents. After complete mixing with the river water, the concentration remained constant over a distance of at least 4 km. Two main substances [Dotarem(®) (Gd-DOTA) and Gadovist(®) (Gd-BT-DO3A)] have been identified in the river water using standards. A gadolinium-based contrast agent, possibly Gd-DOTA (Dotarem(®)), was also detected in water plant samples taken from the Teltow channel. Therefore, uptake of contrast agents [Gadovist(®) (Gd-BTDO3A), Magnevist(®) (Gd-DTPA), Omniscan(®) (Gd-DTPA-BMA), Dotarem(®) (Gd-DOTA), and Multihance(®) (Gd-BOPTA)] by plants was investigated in a model experiment using Lepidium sativum (cress plants). HILIC-ICP-MS was used for identification of different contrast agents, and a first approach for quantification using aqueous standard solutions was tested. For speciation analysis, all investigated contrast agents could be extracted from the plant tissues with a recovery of about 54 % for Multihance(®) (Gd-BOPTA) up to 106 % for Gadovist(®) (Gd-BT-DO3A). These experiments demonstrate that all contrast agents investigated are transported from the roots to the leaves where the highest content was measured.

The potential of oral exposure to calcium and magnesium citrate, a natural product obtained from dolomite, to initiate teratogenesis was analyzed in Wistar rats. Animals received calcium and magnesium citrate oral doses of 250, 500 and 1000 mg/kg during the period of gestation from day 6 to 17 post conception. Maternal, embryo and fetal toxicity was evaluated. Calcium and magnesium citrate exposure did not produce maternal toxicity assessed by clinical observations, body weight gain, food intake, hematology, biochemical parameters and necropsy finding. Signs of embryo-fetal toxicity were not observed. Skeletal and visceral malformations were seen occasionally in all drug-treated and control groups. Skeletal and visceral variations were similar in control and drug-treated groups except for incomplete ossification rib. These finding was spontaneous and unrelated to the drug. In conclusion, in this study we found that the oral exposure to rats of up to 1000 mg/kg of calcium and magnesium citrate during organogenesis did not induce significant maternal and embryo-fetal toxicity. The experimentally derived NOAEL for developmental toxicity was 1000 mg/kg., (Copyright © 2011 Elsevier GmbH. All rights reserved.)

Biomass char was prepared from mulberry branches by physical activation. An examination by Fourier transform infrared spectroscopy (FTIR) indicated that the functional groups of Si-O were mostly burnt out, significantly decreasing the ash content Analysis of data from a scanning electron microscope (SEM) and a Brunauer-Emmett-Teller (BET) test also revealed increased surface roughness and pore structure, which improved the adsorption capacity of biomass char after preparation. The optimum conditions for preparation were found to be pyrolysis at 700 degrees C for 30 minutes, and then activation at 750 degrees C for one hour, with 3.4% steam content for the activating agent. The prepared biomass char was then employed to adsorb ammonium, copper(II) actetate [Cu(II)] and hexavalent chromium [Cr(VI)] in a solution. The results indicated that the prepared biomass char had a better adsorptive performance than the raw material. Moreover, the removal of determinands increased along with the dosage, and the highest adsorption efficiency of ammonium, copper(II) acetate [Cu(II)] and hexavalent chromium [Cr(VI)] were found to be 20%, 100% and 50%, respectively. The adsorptions of ammonium and hexavalent chromium [Cr(VI)] can be simulated by a pseudo-second order model, while the adsorption of copper(II) acetate [Cu(II)] is better simulated by a pseudo-first order model. The adsorption isotherms of copper(II) acetate [Cu(II)] by biomass char were also investigated, and the Langmuir isotherm was found to best describe the adsorption process.

Two multinuclear palladium(II) complexes have been isolated as decomposition products resulting from P-Cl and P-C bond cleavage in (R(P),R(P)/S(P),S(P))-[PdCl(2){1,2-(P(t)BuCl)(2)C(2)B(10)H(10)}] in dichloromethane.

The studies described here show that a relatively low molecular weight, narrow polydispersity polyethylene (PE) wax (Polywax) can serve as a nontoxic and nonvolatile alternative to alkane solvents in monophasic catalytic organic reactions where catalysts and products are separated under biphasic conditions. In this application, a polymer that is a solid at room temperature substitutes for a conventional alkane solvent at ca. 80 °C. In addition to the advantages of being a nonvolatile, nontoxic, reusable solvent, this hydrocarbon polymer solvent, like heptane, can sequester nonpolar soluble polymer-bound catalysts after a reaction and separate them from products. The extent of this separation and its generality were studied using polyisobutylene (PIB)- and poly(4-dodecylstyrene)-bound dyes and PE-bound Pd allylic substitution catalysts, PIB-bound Pd cross-coupling catalysts, and PE- and PIB-bound metathesis catalysts. Catalytic reactions were effected using single-phase reaction mixtures containing Polywax with toluene, THF, or THF/DMF at ca. 80 °C. These solutions either separate into two liquid phases on addition of a perturbing agent or separate as a solid/liquid mixture on cooling. The hydrocarbon polymer-bound dyes or catalysts either separate into the hot liquid Polywax phase or coprecipitate with Polywax and are subsequently isolated as a nonvolatile Polywax solid phase that contains the dye or the recyclable catalyst.

To observe molecular orbitals using scanning tunneling microscopy, well-ordered oxidized layers on Cu(001) were fabricated to screen the individual adsorbed cobalt phthalocyanine (CoPc) molecules from the electronic influence of the metal surface. Scanning tunneling microscope images of the molecule on this oxidized layer show similarities to the orbital distribution of the free molecule. The good match between the differential conductance mapping images and the calculated charge distribution at energy levels corresponding to the frontier orbitals of CoPc provides more evidence of the screening of the oxidized layer from interactions between the metal surface and supported molecules., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Introduction: A new method combining (68)Ga-labeling and steam sterilization, here called autoclabeling, has been evaluated for two somatostatin receptor binding tracers used for positron emission tomography (PET) imaging of neuroendocrine tumors; DOTA-TATE and -NOC., Methods: The two peptides DOTA-TATE and -NOC were labeled with (68)Ga by heating for 15 min at 121°C in the presence of acetate buffer at pH 4.3. The product solutions were tested for sterility, presence of endotoxins, degradation of peptide and osmolality., Results: Complete incorporation of (68)Ga was obtained after the autoclabeling reaction and no degradation of the peptides was observed. Sterility was verified and the presence of endotoxins was well within Ph. Eur limits (175IU/maximum injected volume)., Conclusions: The autoclabeling method provides a convenient procedure for (68)Ga-labeling by combining the labeling reaction and steam sterilization into one single step., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

This work describes the development of a fast method for speciation analysis of triethyl-lead and tributyl-tin species in urine samples after in situ derivatization by tetraethyl- or tetrapropyl-borate reagents. The alkylation reaction is done in the aqueous and urine medium and the less-polar derivatives are extracted in hexane by liquid-liquid extraction. The species were extracted and the extract was efficiently collected from the aqueous phase after centrifugation. Finally, the organometallic species are separated by gas chromatography and determined from the emission signals of elemental lead and tin. Atomic lead and tin are formed from the organolead and organotin compounds during atomization of the column eluate in a microwave-induced helium plasma source. The simultaneous measurement of lead (Pb) at 405.780 nm and tin (Sn) at 303.419 nm was achieved by an atomic emission detector. Finally, the analytes were determined with satisfactory precision (<5%) and detection limits of 0.05 μg Pb/L and 0.48 μg Sn/L, respectively, when 10 mL of urine is extracted with 1 mL of hexane and 1 μL of extract is injected., (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We report the isolation and characterization of arylpalladium cyanide complexes that undergo reductive elimination to form arylnitriles. The rates of reductive elimination from a series of arylpalladium cyanide complexes reveal that the electronic effects on the reductive elimination from arylpalladium cyanide complexes are distinct from those on reductive reductive eliminations from arylpalladium alkoxo, amido, thiolate, and enolate complexes. Arylpalladium cyanide complexes containing aryl ligands with electron-donating substituents undergo reductive elimination of aromatic nitriles faster than complexes containing aryl ligands with electron-withdrawing substituents. In addition, the transition state for the reductive elimination of the aromatic nitrile is much different from that for reductive eliminations that occur from most other arylpalladium complexes. Computational studies indicate that the reductive elimination of an arylnitrile from Pd(II) occurs through a transition state more closely related in structure and electronic distribution to that for the insertion of CO into a palladium-aryl bond.

The absorption, emission and excitation spectra of ZnPc and H(2)Pc trapped in Ne, N(2), Ar, Kr and Xe matrices have been recorded in the region of the Q states. A comparison of the matrix fluorescence spectra with Raman spectra recorded in KBr pellets reveals very strong similarities. This is entirely consistent with the selection rules and points to the occurrence of only fundamental vibrational transitions in the emission spectra. Based on this behaviour, the vibronic modes in emission have been assigned using results obtained recently on the ground state with large basis-set DFT calculations [Murray et al. PCCP, 12, 10406 (2010)]. Furthermore, the very strong mirror symmetry between excitation and emission has allowed these assignments to be extended to the excitation (absorption) bands. While this approach works well for ZnPc, coupling between the band origin of the S(2)(Q(Y)) state and vibrationally excited levels of S(1)(Q(X)), limits the range of its application in H(2)Pc. The Q(X)/Q(Y) state coupling is analysed from data obtained from site-selective excitation spectra, revealing pronounced matrix and site effects. From this analysis, the splitting of the Q(X) and Q(Y) states has been determined more accurately than in any previous attempts., (This journal is © the Owner Societies 2011)

The facilitated ion transfer (FIT) of uranyl or dioxouranium (UO(2)(2+)) was studied electrochemically using a micro interface between two immiscible electrolytic solutions (micro-ITIES) in order to evaluate the complexation stoichiometry and complexation constants (β) of two widely used ligands in spent fuel reprocessing: tributylphosphate (TBP) and octyl(phenyl)-N,N-diisobutylcarbamoylmethyl-phosphine oxide (CMPO). For the first time, discrete interfacial complexation reaction steps of varying uranyl to the two ligands ratios were resolved using the micro-ITIES hosted at the tip of a 25 μm diameter glass capillary. Two stoichiometries for UO(2)NO(3)TBP(n)(+) were determined including n = 3 and 4 with β values of 3.2 × 10(11) and 3.9 × 10(13), respectively. Subsequently, three distinct complexation reactions of CMPO with UO(2)(2+) were discovered corresponding to UO(2)NO(3)CMPO(2)(+), UO(2)NO(3)CMPO(3)(+), and UO(2)CMPO(5)(2+) whose respective complexation constants were determined to be 8.0 × 10(11), 8.8 × 10(14), and 6.5 × 10(32). The participation of nitrate anions in these complexation reactions is also discussed.