Sample records for lanthanide shift reagents

  1. Lanthanide Complexes as Nuclear Magnetic Resonance Structural Probes: Paramagnetic Anisotropy of Shift Reagent Adducts

    Microsoft Academic Search

    William Dew. Horrocks Jr.; James P. Sipe III

    1972-01-01

    Magnetic anisotropy measurements on single crystals of a series of paramagnetic 8-coordinate lanthanide shift reagent adducts of the type Ln[(CH3)3CCOCHCOC(CH3)3]3(4- CH3C5H4N)2 have been made for the following lanthanides: praseodymium, neodymium, samarium, europium, terbium, dysprosium, holmium, erbium, thulium, and ytterbium. The susceptibility tensors are highly anisotropic and nonaxial. Dipolar nuclear magnetic resonance shifts evaluated from the solid-state data are in satisfactory

  2. Pressure effect of the /sup 1/H NMR spectra of organic compounds in the presence of lanthanide shift reagents. A formally associative process characterized by volume expansion

    SciTech Connect

    Schulman, E.M.; Cheung, C.K.; Merbach, A.E.; Yamada, H.; le Noble, W.J.

    1987-11-11

    Following the successful application of hydrostatic pressure in mechanistic investigations of organic reactions, chemists have launched a vigorous effort to apply this tool to substitution reactions of coordination compounds. The authors began to study pressure effects in the NMR spectra of keton-lanthanide combination with the hope that the increase shifts anticipated might enhance the utility of the method, perhaps even expand its applicability to new classes of compounds. 5-Phenyl- and 5-tert-butyladamantan-2-one, piperidine, tetrahydrofuran, and cyclopentanol exhibited pressure-reduced lanthanide-induced shifts with Eu(fod)/sub 3/; Yb(fob)/sub 3/ and the shielding reagent Pr(fod)/sub 3/ showed the same effect with adamantanone. Solvent variations (CD/sub 2/Cl/sub 2/, CCl/sub 4/) caused minor changes in the magnitude of these shifts but did not reverse any. With the objective of learning whether these effects are due to a suppressed equilibrium population or to a reduction in the bound shift of the complex, they measured the spectra for a series or equimolar solutions of adamantanone and Eu(fod)/sub 3/ in CDCl/sub 3/ and used the Bouquant-Chuche equation to calculate both. Reasonable agreement with known atmosphere pressure data was obtained.

  3. Assignments of normally unoccupied orbitals to the temporary negative ion states of several lanthanide NMR shift reagents and comments on resonance involvement in electron circular dichroism.

    PubMed

    Scheer, A M; Gallup, G A; Gay, T J

    2008-05-01

    We have measured the total electron scattering cross sections of several NMR shift reagent molecules X(hfc)3, where X = Yb, Er, Eu and Pr, by means of electron transmission spectroscopy (ETS) to determine their vertical attachment energies. A strong low-energy resonance (<1 eV) is observed in all of the compounds except for Yb(hfc)3. We explain this anomaly in terms of the ground-state electron configuration of each molecule. Also, with the aid of restricted open-shell Hartree-Fock (ROHF) calculations on analogous molecules with truncated fluorocarbon chains, we have assigned specific normally unoccupied orbitals to the resonances observed in ETS. To our knowledge, these molecules are the largest for which this procedure has been successfully completed. Nolting et al. (J. Phys. B 1997, 30, 5491) have demonstrated that the above NMR shift reagents exhibit electron circular dichroism (ECD) between 1 and 10 eV. Using our new total cross section data, we comment on the possibility of resonance involvement in the generation of ECD. PMID:18370426

  4. Selectivity enhancement of Arsenazo(III) reagent towards heavier lanthanides using polyaminocarboxylic acids: A spectrophotometric study.

    PubMed

    Matharu, Komal; Mittal, Susheel K; Ashok Kumar, S K; Sahoo, Suban K

    2015-06-15

    A new study has been conducted to quantify lanthanide(III) ions using Arsenazo III-polyaminocarboxylic acid (PACA) system. The study disclosed two different analytically important information: (i) ?max of lanthanide-Arsenazo III complexes for lighter lanthanides like Ce(III) and Nd(III) did not shift from its original position on addition of PACA and (ii) for heavier lanthanides like Dy(III), Tm(III) and Lu(III) a new ?max at 538nm was observed, while wavelengths at 610nm and 654nm were disappeared in presence of ethylenediaminetertracetic acid (EDTA) and trans-1,2-Diaminocyclohexane-N,N,N',N'-tetraacetic acid (DCTA), further the intensity of peak decreased with increase in lanthanide(III) ion concentration. Effect of ethylene glycol-bis(2-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA) and N-(2-hydroxyethyl) ethylenediamine-N,N',N'-triacetic acid (EDTA-OH) on Arsenzo(III)-Ln(III) complex is very weak and there is no analytically importance of such interaction. Moreover, this work confirms that Nd(III) and heavy lanthanides can be successfully determined with high accuracy in the working range of concentration of these metal ions. PMID:25770966

  5. Noninvasive thermometry using hyperfine-shifted MR signals from paramagnetic lanthanide complexes.

    PubMed

    Hekmatyar, S K; Kerkhoff, R M; Pakin, S K; Hopewell, P; Bansal, N

    2005-09-01

    MR thermometry techniques based on the strong water 1H signal provide high spatial and temporal resolution and have shown promise for applications such as laser surgery and RF ablation. However, these techniques have low temperature sensitivity for hyperthermia applications and are greatly influenced by local motion and susceptibility variations. 1H NMR signals from paramagnetic lanthanide complexes of Pr3+, Yb3+ and Tm3+ show up to 300-fold stronger temperature dependence compared to the water 1H signal. In addition, 1H chemical shifts of many of these complexes are insensitive to other factors such as the concentration of the paramagnetic complex, pH, [Ca2+], and the presence of plasma macro-molecules and ions. Applications of lanthanide complexes for temperature measurement in intact animals and the feasibility of mapping temperatures in phantoms have been demonstrated. Among all the lanthanide complexes examined so far, thulium 1, 4, 7, 10-tetramethyl-1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetate (TmDOTMA-) appears to be the most attractive for in vivo MR thermometry. The 1H signal from the methyl groups on this complex is relatively intense because of 12 equivalent protons and provides high temperature sensitivity because of the large paramagnetic shifts induced by thulium. The possibility of imaging TmDOTMA2--in intact animals at physiologically safe concentrations has recently been demonstrated. Overall, MR thermometry methods based on hyperfine-shifted MR signals from paramagnetic lanthanide complexes appear promising for animal applications, but further studies relating to acceptable dose and signal-to-noise ratio are necessary before clinical use. PMID:16147440

  6. Highly Emitting Near-Infrared Lanthanide “Encapsulated Sandwich” Metallacrown Complexes with Excitation Shifted Toward Lower Energy

    PubMed Central

    2015-01-01

    Near-infrared (NIR) luminescent lanthanide complexes hold great promise for practical applications, as their optical properties have several complementary advantages over organic fluorophores and semiconductor nanoparticles. The fundamental challenge for lanthanide luminescence is their sensitization through suitable chromophores. The use of the metallacrown (MC) motif is an innovative strategy to arrange several organic sensitizers at a well-controlled distance from a lanthanide cation. Herein we report a series of lanthanide “encapsulated sandwich” MC complexes of the form Ln3+[12-MCZn(II),quinHA-4]2[24-MCZn(II),quinHA-8] (Ln3+[Zn(II)MCquinHA]) in which the MC framework is formed by the self-assembly of Zn2+ ions and tetradentate chromophoric ligands based on quinaldichydroxamic acid (quinHA). A first-generation of luminescent MCs was presented previously but was limited due to excitation wavelengths in the UV. We report here that through the design of the chromophore of the MC assembly, we have significantly shifted the absorption wavelength toward lower energy (450 nm). In addition to this near-visible inter- and/or intraligand charge transfer absorption, Ln3+[Zn(II)MCquinHA] exhibits remarkably high quantum yields, long luminescence lifetimes (CD3OD; Yb3+, QLnL = 2.88(2)%, ?obs = 150.7(2) ?s; Nd3+, QLnL = 1.35(1)%, ?obs = 4.11(3) ?s; Er3+, QLnL = 3.60(6)·10–2%, ?obs = 11.40(3) ?s), and excellent photostability. Quantum yields of Nd3+ and Er3+ MCs in the solid state and in deuterated solvents, upon excitation at low energy, are the highest values among NIR-emitting lanthanide complexes containing C–H bonds. The versatility of the MC strategy allows modifications in the excitation wavelength and absorptivity through the appropriate design of the ligand sensitizer, providing a highly efficient platform with tunable properties. PMID:24432702

  7. Generation of pseudocontact shifts in proteins with lanthanides using small "clickable" nitrilotriacetic Acid and iminodiacetic Acid tags.

    PubMed

    Loh, Choy-Theng; Graham, Bim; Abdelkader, Elwy H; Tuck, Kellie L; Otting, Gottfried

    2015-03-23

    Pseudocontact shifts (PCS) induced by paramagnetic lanthanide ions provide unique long-range structural information in nuclear magnetic resonance (NMR) spectra, but the site-specific attachment of lanthanide tags to proteins remains a challenge. Here we incorporated p-azido-phenylalanine (AzF) site-specifically into the proteins ubiquitin and GB1, and ligated the AzF residue with alkyne derivatives of small nitrilotriacetic acid and iminodiacetic acid tags using the Cu(I) -catalysed "click" reaction. These tags form lanthanide complexes with no or only a small net charge and produced sizeable PCSs with paramagnetic lanthanide ions in all mutants tested. The PCSs were readily fitted by single magnetic susceptibility anisotropy tensors. Protein precipitation during the click reaction was greatly alleviated by the presence of 150?mM NaCl. PMID:25676727

  8. Shifts in protein charge state distributions with varying redox reagents in nanoelectrospray triple quadrupole mass spectrometry.

    PubMed

    Zhao, Cheng; Wood, Troy D; Bruckenstein, Stanley

    2005-03-01

    The influence of a number of redox reagents on the charge state distribution in nanoelectrospray mass spectrometry was examined using cytochrome c and ubiquitin. The redox active species investigated were: 1,4-benzoquinone, quinhydrone, tetracyanoquinodimethane (TCNQ), hydroquinone, and ascorbic acid. The redox active species was mixed with the protein sample before injection into the nanoelectrospray emitter, and mass spectra were acquired using a triple quadrupole mass spectrometer. Under the same experimental conditions, the charge state distribution of cytochrome c was observed to shift from a weighted average charge state of 14.25 (in the absence of redox species) to 7.10 in the presence of 1,4-benzoquinone. When quinhydrone was mixed with cytochrome c, the charge state distribution of the protein also shifted to lower charge states (weighted average charge state = 9.43), indicative of less charge state reduction for quinhydrone than with 1,4-benzoquinone. Addition of the redox reagent had little effect on the conformation of cytochrome c, as indicated by far ultraviolet circular dichroism spectra. In contrast, the reagents TCNQ, hydroquinone, and ascorbic acid exhibited negligible effects on the observed charge state distribution of the protein. The differing results for these redox reagents can be rationalized in terms of the redox half reactions involving these species. The results observed with ubiquitin upon adding quinhydrone were analogous to those observed with cytochrome c. PMID:15734335

  9. Lanthanide IonInduced Isotropic Shifts and Broadening for Nuclear Magnetic Resonance Structural Analysis of Model Membranes

    Microsoft Academic Search

    S. Brian Andrews; J. W. Faller; James M. Gilliam; Russell J. Barrnett

    1973-01-01

    The effects of a series of aquated lanthanide ions on the nuclear magnetic resonance spectrum of phospholipid bilayer suspensions are reported. The ability of these ions to provide a spectral distinction between morphologically exterior resonances and their interior counterparts was confirmed. Measurements of the relative shifting and broadening capabilities of these ions are reported, and their correlation with solid-state magnetic

  10. Biological and Clinical Aspects of Lanthanide Coordination Compounds

    PubMed Central

    Misra, Sudhindra N.; M., Indira Devi; Shukla, Ram S.

    2004-01-01

    The coordinating chemistry of lanthanides, relevant to the biological, biochemical and medical aspects, makes a significant contribution to understanding the basis of application of lanthanides, particularly in biological and medical systems. The importance of the applications of lanthanides, as an excellent diagnostic and prognostic probe in clinical diagnostics, and an anticancer material, is remarkably increasing. Lanthanide complexes based X-ray contrast imaging and lanthanide chelates based contrast enhancing agents for magnetic resonance imaging (MRI) are being excessively used in radiological analysis in our body systems. The most important property of the chelating agents, in lanthanide chelate complex, is its ability to alter the behaviour of lanthanide ion with which it binds in biological systems, and the chelation markedly modifies the biodistribution and excretion profile of the lanthanide ions. The chelating agents, especially aminopoly carboxylic acids, being hydrophilic, increase the proportion of their complex excreted from complexed lanthanide ion form biological systems. Lanthanide polyamino carboxylate-chelate complexes are used as contrast enhancing agents for Magnetic Resonance Imaging. Conjugation of antibodies and other tissue specific molecules to lanthanide chelates has led to a new type of specific MRI contrast agents and their conjugated MRI contrast agents with improved relaxivity, functioning in the body similar to drugs. Many specific features of contrast agent assisted MRI make it particularly effective for musculoskeletal and cerebrospinal imaging. Lanthanide-chelate contrast agents are effectively used in clinical diagnostic investigations involving cerebrospinal diseases and in evaluation of central nervous system. Chelated lanthanide complexes shift reagent aided 23Na NMR spectroscopic analysis is used in cellular, tissue and whole organ systems. PMID:18365075

  11. The solution structure of Ln (DOTP) 5- complexxes. A comparison of lanthanide-induced paramagnetic shifts with the MMX energy-minimized structure

    NASA Astrophysics Data System (ADS)

    Geraldes, Carlos F. G. C.; Sherry, A. Dean; Kiefer, Garry E.

    Complexes between the trivalent lanthanide ions and the macrocyclic chelate 1,4,7,10-tetraazacyclododecane- N,N',N?,N?-tetra(methylene phosphonate) (DOTP) have been examined by high-resolution NMR spectroscopy. The proton spectra of the diamagnetic La(DOTP) 5- and Lu(DOTP) 5- complexes provide evidence for very rigid chelate structures with the ethylenediamine-containing chelate rings essentially locked into a single conformation at room temperature. The activation energy for ethylenediamine chelate ring interconversions in these complexes is approximately 100 kJ mol -1, considerably higher than that reported previously for the corresponding Ln(DOTA) - complexes (DOTA is the tetraacetate analog of DOTP). Lanthanide-induced shifts are reported for all 1H, 13C, and 31P nuclei in 11 Ln(DOTP) 5- complexes. The proton spectra of these complexes display unusually large lanthanide-induced shifts, one showing a spectrum in which the 1H resonances span 900 ppm. The contact and pseudocontact contributions to these shifts were separated using Reilley's temperature-independent method and the resulting pseudocontact lanthanide-induced NMR shifts were in excellent agreement with those calculated for a structure derived using MMX molecular modeling methods. The pseudocontact shifts provide evidence for Ln (DOTP) 5- chelates which have virtually identical structures along the lanthanide series, with the possible exception of Tm(DOTP) 5-.

  12. Strategies for the uses of lanthanide NMR shift probes in the determination of protein structure in solutio. Application to the EF calcium binding site of carp parvalbumin.

    PubMed Central

    Lee, L; Sykes, B D

    1980-01-01

    The homologous sequences observed for many calcium binding proteins such as parvalbumin, troponin C, the myosin light chains, and calmodulin has lead to the hypothesis that these proteins have homologous structures at the level of their calcium binding sites. This paper discusses the development of a nuclear magnetic resonance (NMR) technique which will enable us to test this structural hypothesis in solution. The technique involves the substitution of a paramagnetic lanthanide ion for the calcium ion which results in lanthanide induced shifts and broadening in the 1H NMR spectrum of the protein. These shifts are sensitive monitors of the precise geometrical orientation of each proton nucleus relative to the metal. The values of several parameters in the equation relating the NMR shifts to the structure are however known as priori. We have attempted to determine these parameters, the orientation and principal elements of the magnetic susceptibility tensor of the protein bound metal, by studying the lanthanide induced shifts for the protein parvalbumin whose structure has been determined by x-ray crystallographic techniques. The interaction of the lanthanide ytterbium with parvalbumin results in high resolution NMR spectra exhibiting a series of resonances with shifts spread over the range 32 to -19 ppm. The orientation and principal elements of the ytterbium magnetic susceptibility tensor have been determined using three assigned NMR resonances, the His-26 C2 and C4 protons and the amino terminal acetyl protons, and seven methyl groups; all with known geometry relative to the EF calcium binding site. The elucidation of these parameters has allowed us to compare the observed spectrum of the nuclei surrounding the EF calcium binding site of parvalbumin with that calculated from the x-ray structure. A significant number of the calculated shifts are larger than any of the observed shifts. We feel that a refinement of the x-ray based proton coordinates will be possible utilizing the geometric information contained in the lanthanide shifted NMR spectrum. PMID:7248448

  13. Shift Reagents for IMS-IMS-MS Analysis of Complex Peptide Mixtures: Evaluation of 18-Crown-6 Ether Complexes

    PubMed Central

    Bohrer, Brian C.; Clemmer, David E.

    2011-01-01

    18-crown-6 ether (18C6) is evaluated as a shift reagent for multidimensional ion mobility spectrometry-mass spectrometry (IMS-IMS-MS) analyses of tryptic protein digests. In this approach, 18C6 is spiked into the solution-phase mixture and noncovalent peptide-crown ion complexes are formed by electrospraying the mixture into the gas phase. After an initial mobility separation in the first IMS drift region, complexes of similar mobility are selected and dissociated via collisional activation prior to entering the second drift region. These dissociation products (including smaller complexes, naked peptide ions, charge transfer products, and fragment ions) differ in mobility from their precursor ion complexes and (in favorable cases) from one another, allowing the mixture to resolve further in the second IMS region. We estimate an IMS-IMS peak capacity of ?2400 when shift reagents are employed. The approach is illustrated by examining a tryptic digest of cytochrome c and by identifying a peptide out of a complex mixture obtained by digestion of human plasma proteins. Disadvantages arising from increased complexity of datasets, as well as other advantages of this approach are considered. PMID:21609128

  14. Secret Lanthanides

    PubMed Central

    Sturza, CM

    2014-01-01

    Abstract Lanthanides are a group of 15 chemical elements which, together with their salts, have come to be used in the last decade as homoeopathic remedies. The effective introduction of lanthanides and their salts into the clinical use, as homoeopathic remedies was based on the idea of Jan Scholten, MD to relate their physicochemical properties shown in the periodic table of elements to their homoeopathic potential. The lanthanides and their salts were prepared as homoeopathic remedies by Pharmacist Robert Münz. PMID:25408760

  15. Secret lanthanides.

    PubMed

    Sturza, C M

    2014-09-15

    Lanthanides are a group of 15 chemical elements which, together with their salts, have come to be used in the last decade as homoeopathic remedies. The effective introduction of lanthanides and their salts into the clinical use, as homoeopathic remedies was based on the idea of Jan Scholten, MD to relate their physicochemical properties shown in the periodic table of elements to their homoeopathic potential. The lanthanides and their salts were prepared as homoeopathic remedies by Pharmacist Robert Münz. PMID:25408760

  16. Shift reagents for multidimensional ion mobility spectrometry-mass spectrometry analysis of complex peptide mixtures: evaluation of 18-crown-6 ether complexes.

    PubMed

    Bohrer, Brian C; Clemmer, David E

    2011-07-01

    18-Crown-6 ether (18C6) is evaluated as a shift reagent for multidimensional ion mobility spectrometry-mass spectrometry (IMS-IMS-MS) analyses of tryptic protein digests. In this approach, 18C6 is spiked into the solution-phase mixture and noncovalent peptide-crown ion complexes are formed by electrospraying the mixture into the gas phase. After an initial mobility separation in the first IMS drift region, complexes of similar mobility are selected and dissociated via collisional activation prior to entering the second drift region. These dissociation products (including smaller complexes, naked peptide ions, charge transfer products, and fragment ions) differ in mobility from their precursor ion complexes and (in favorable cases) from one another, allowing the mixture to resolve further in the second IMS region. We estimate an IMS-IMS peak capacity of ~2400 when shift reagents are employed. The approach is illustrated by examining a tryptic digest of cytochrome c and by identifying a peptide out of a complex mixture obtained by digestion of human plasma proteins. Disadvantages arising from increased complexity of data sets as well as other advantages of this approach are considered. PMID:21609128

  17. 4 fn-1 5 d centroid shift in lanthanides and relation with anion polarizability, covalency, and cation electronegativity

    NASA Astrophysics Data System (ADS)

    Dorenbos, P.; Andriessen, J.; van Eijk, C. W. E.

    2003-02-01

    Data collected on the centroid shift of the 5 d-configuration of Ce 3+ in oxide and fluoride compounds were recently analyzed with a model involving the correlated motion between 5 d-electron and ligand electrons. The correlation effects are proportional to the polarizability of the anion ligands and it leads, like covalency, to lowering of the 5 d-orbital energies. By means of ab initio Hartree-Fock-LCAO calculations including configuration interaction the contribution from covalency and correlated motion to the centroid shift are determined separately for Ce 3+ in various compounds. It will be shown that in fluoride compounds, covalency provides an insignificant contribution. In oxides, polarizability appears to be of comparable importance as covalency.

  18. Method bacterial endospore quantification using lanthanide dipicolinate luminescence

    NASA Technical Reports Server (NTRS)

    Ponce, Adrian (Inventor); Venkateswaran, Kasthuri J. (Inventor); Kirby, James Patrick (Inventor)

    2007-01-01

    A lanthanide is combined with a medium to be tested for endospores. The dipicolinic acid released from the endospores binds the lanthanides, which have distinctive emission (i.e., luminescence) spectra, and are detected using photoluminescence. The concentration of spores is determined by preparing a calibration curve generated from photoluminescence spectra of lanthanide complex mixed with spores of a known concentration. A lanthanide complex is used as the analysis reagent, and is comprised of lanthanide ions bound to multidentate ligands that increase the dipicolinic acid binding constant through a cooperative binding effect with respect to lanthanide chloride. The resulting combined effect of increasing the binding constant and eliminating coordinated water and multiple equilibria increase the sensitivity of the endospore assay by an estimated three to four orders of magnitude over prior art of endospore detection based on lanthanide luminescence.

  19. Luminescent lanthanide chelates and methods of use

    DOEpatents

    Selvin, Paul R. (Berkeley, CA); Hearst, John (Berkeley, CA)

    1997-01-01

    The invention provides lanthanide chelates capable of intense luminescence. The celates comprise a lanthanide chelator covalently joined to a coumarin-like or quinolone-like sensitizer. Exemplary sensitzers include 2- or 4-quinolones, 2- or 4-coumarins, or derivatives thereof e.g. carbostyril 124 (7-amino-4-methyl-2-quinolone), coumarin 120 (7-amino-4-methyl-2-coumarin), coumarin 124 (7-amino-4-(trifluoromethyl)-2-coumarin), aminomethyltrimethylpsoralen, etc. The chelates form high affinity complexes with lanthanides, such as terbium or europium, through chelator groups, such as DTPA. The chelates may be coupled to a wide variety of compounds to create specific labels, probes, diagnostic and/or therapeutic reagents, etc. The chelates find particular use in resonance energy transfer between chelate-lanthanide complexes and another luminescent agent, often a fluorescent non-metal based resonance energy acceptor. The methods provide useful information about the structure, conformation, relative location and/or interactions of macromolecules.

  20. Lanthanide ion (III) complexes of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraaminophosphonate for dual biosensing of pH with chemical exchange saturation transfer (CEST) and biosensor imaging of redundant deviation in shifts (BIRDS).

    PubMed

    Huang, Yuegao; Coman, Daniel; Ali, Meser M; Hyder, Fahmeed

    2015-01-01

    Relaxivity-based magnetic resonance of phosphonated ligands chelated with gadolinium (Gd(3+) ) shows promise for pH imaging. However instead of monitoring the paramagnetic effect of lanthanide complexes on the relaxivity of water protons, biosensor (or molecular) imaging with magnetic resonance is also possible by detecting either the nonexchangeable or the exchangeable protons on the lanthanide complexes themselves. The nonexchangeable protons (e.g. -CHx , where 3???x???1) are detected using a three-dimensional chemical shift imaging method called biosensor imaging of redundant deviation in shifts (BIRDS), whereas the exchangeable protons (e.g. -OH or -NHy , where 2???y???1) are measured with chemical exchange saturation transfer (CEST) contrast. Here we tested the feasibility of BIRDS and CEST for pH imaging of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraaminophosphonate (DOTA-4AmP(8-) ) chelated with thulium (Tm(3+) ) and ytterbium (Yb(3+) ). BIRDS and CEST experiments show that both complexes are responsive to pH and temperature changes. Higher pH and temperature sensitivities are obtained with BIRDS for either complex when using the chemical shift difference between two proton resonances vs using the chemical shift of a single proton resonance, thereby eliminating the need to use water resonance as reference. While CEST contrast for both agents is linearly dependent on pH within a relatively large range (i.e. 6.3-7.9), much stronger CEST contrast is obtained with YbDOTA-4AmP(5-) than with TmDOTA-4AmP(5-) . In addition, we demonstrate the prospect of using BIRDS to calibrate CEST as new platform for quantitative pH imaging. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24801742

  1. Fracture-resistant lanthanide scintillators

    DOEpatents

    Doty, F. Patrick (Livermore, CA)

    2011-01-04

    Lanthanide halide alloys have recently enabled scintillating gamma ray spectrometers comparable to room temperature semiconductors (<3% FWHM energy resolutions at 662 keV). However brittle fracture of these materials upon cooling hinders the growth of large volume crystals. Efforts to improve the strength through non-lanthanide alloy substitution, while preserving scintillation, have been demonstrated. Isovalent alloys having nominal compositions of comprising Al, Ga, Sc, Y, and In dopants as well as aliovalent alloys comprising Ca, Sr, Zr, Hf, Zn, and Pb dopants were prepared. All of these alloys exhibit bright fluorescence under UV excitation, with varying shifts in the spectral peaks and intensities relative to pure CeBr.sub.3. Further, these alloys scintillate when coupled to a photomultiplier tube (PMT) and exposed to .sup.137Cs gamma rays.

  2. Lanthanide-halide based humidity indicators

    DOEpatents

    Beitz, James V. (Hinsdale, IL); Williams, Clayton W. (Chicago, IL)

    2008-01-01

    The present invention discloses a lanthanide-halide based humidity indicator and method of producing such indicator. The color of the present invention indicates the humidity of an atmosphere to which it is exposed. For example, impregnating an adsorbent support such as silica gel with an aqueous solution of the europium-containing reagent solution described herein, and dehydrating the support to dryness forms a substance with a yellow color. When this substance is exposed to a humid atmosphere the water vapor from the air is adsorbed into the coating on the pore surface of the silica gel. As the water content of the coating increases, the visual color of the coated silica gel changes from yellow to white. The color change is due to the water combining with the lanthanide-halide complex on the pores of the gel.

  3. Ionization Energies of Lanthanides

    ERIC Educational Resources Information Center

    Lang, Peter F.; Smith, Barry C.

    2010-01-01

    This article describes how data are used to analyze the pattern of ionization energies of the lanthanide elements. Different observed pathways of ionization between different ground states are discussed, and the effects of pairing, exchange, and orbital interactions on ionization energies of the lanthanides are evaluated. When all the above…

  4. The Lanthanide Contraction Revisited

    SciTech Connect

    Seitz, Michael; Oliver, Allen G.; Raymond, Kenneth N.

    2007-04-19

    A complete, isostructural series of lanthanide complexes (except Pm) with the ligand TREN-1,2-HOIQO has been synthesized and structurally characterized by means of single-crystal X-ray analysis. All complexes are 1D-polymeric species in the solid state, with the lanthanide being in an eight-coordinate, distorted trigonal-dodecahedral environment with a donor set of eight unique oxygen atoms. This series constitutes the first complete set of isostructural lanthanide complexes with a ligand of denticity greater than two. The geometric arrangement of the chelating moieties slightly deviates across the lanthanide series, as analyzed by a shape parameter metric based on the comparison of the dihedral angles along all edges of the coordination polyhedron. The apparent lanthanide contraction in the individual Ln-O bond lengths deviates considerably from the expected quadratic decrease that was found previously in a number of complexes with ligands of low denticity. The sum of all bond lengths around the trivalent metal cation, however, is more regular, showing an almost ideal quadratic behavior across the entire series. The quadratic nature of the lanthanide contraction is derived theoretically from Slater's model for the calculation of ionic radii. In addition, the sum of all distances along the edges of the coordination polyhedron show exactly the same quadratic dependency as the Ln-X bond lengths. The universal validity of this coordination sphere contraction, concomitant with the quadratic decrease in Ln-X bond lengths, was confirmed by reexamination of four other, previously published, almost complete series of lanthanide complexes. Due to the importance of multidentate ligands for the chelation of rare-earth metals, this result provides a significant advance for the prediction and rationalization of the geometric features of the corresponding lanthanide complexes, with great potential impact for all aspects of lanthanide coordination.

  5. RAS Reference Reagents

    Cancer.gov

    Posted: September 22, 2014 Posted: September 22, 2014 RAS Reference Reagents Reference Reagents Group An important priority of the RAS Initiative is to distribute highly validated materials and methods to the world-wide community of RAS researchers.

  6. Handling Pyrophoric Reagents

    SciTech Connect

    Alnajjar, Mikhail S.; Haynie, Todd O.

    2009-08-14

    Pyrophoric reagents are extremely hazardous. Special handling techniques are required to prevent contact with air and the resulting fire. This document provides several methods for working with pyrophoric reagents outside of an inert atmosphere.

  7. Basics of Lanthanide Photophysics

    Microsoft Academic Search

    Jean-Claude G. Bünzli; Svetlana V. Eliseeva

    \\u000a The fascination for lanthanide optical spectroscopy dates back to the 1880s when renowned scientists such as Sir William Crookes,\\u000a LeCoq de Boisbaudran, Eugène Demarçay or, later, Georges Urbain were using luminescence as an analytical tool to test the\\u000a purity of their crystallizations and to identify potential new elements. The richness and complexity of lanthanide optical\\u000a spectra are reflected in an

  8. Synthesis and characterisation of luminescent lanthanide dyes for solar energy conversion 

    E-print Network

    Congiu, Martina

    2013-06-29

    Lanthanide (III) complexes are used extensively in solar conversion devices, such as Luminescent Solar Concentrators (LSCs) and Luminescent Down-Shifting (LDS) for their peculiar characteristics of narrow band emission, ...

  9. Spectrophotometric, potentiometric, and gravimetric determination of lanthanides with peri-dihydroxynaphthindenone

    SciTech Connect

    Hassan, S.S.M.; Mahmoud, W.H.

    1982-02-01

    Sensitive and reasonably selective methods are described for the spectrophotometric, potentiometric, and gravimetric determination of lanthanides using peri-dihydroxynaphthindenone as a novel chromogenic and precipitating reagent. The reagent forms a stable 1:2 (metal:reagent) type of complex with light lanthanides at pH 2-7 in 1:1 ethanol-water mixture. Low metal concentrations (<10 ..mu..g/mL) develop colored species (lambda/sub max/ 580 to 590 nm, epsilon/sub max/ (4-6) x 10/sup 4/ L mol/sup -1/ cm/sup -1/) which obey Beer's law. Quantitative precipitation of the complexes from metal solutions of concentrations > 100 ..mu..g/mL permits both gravimetric quantitation by igniting the precipitates to the metal oxides and potentiometric titration of the excess reagent. Results with an average recovery of 98% (standard deviation 0.7%) are obtainable for 0.1 ..mu..g to 200 mg of all light lanthanides. Many foreign ions naturally occurring or frequently associated with lanthanides do not interfere or can be tolerated.

  10. Luminescent macrocyclic lanthanide complexes

    DOEpatents

    Raymond, Kenneth N; Corneillie, Todd M; Xu, Jide

    2014-05-20

    The present invention provides a novel class of macrocyclic compounds as well as complexes formed between a metal (e.g., lanthanide) ion and the compounds of the invention. Preferred complexes exhibit high stability as well as high quantum yields of lanthanide ion luminescence in aqueous media without the need for secondary activating agents. Preferred compounds incorporate hydroxy-isophthalamide moieties within their macrocyclic structure and are characterized by surprisingly low, non-specific binding to a variety of polypeptides such as antibodies and proteins as well as high kinetic stability. These characteristics distinguish them from known, open-structured ligands.

  11. Luminescent macrocyclic lanthanide complexes

    DOEpatents

    Raymond, Kenneth N. (Berkeley, CA); Corneillie, Todd M. (Campbell, CA); Xu, Jide (Berkeley, CA)

    2012-05-08

    The present invention provides a novel class of macrocyclic compounds as well as complexes formed between a metal (e.g., lanthanide) ion and the compounds of the invention. Preferred complexes exhibit high stability as well as high quantum yields of lanthanide ion luminescence in aqueous media without the need for secondary activating agents. Preferred compounds incorporate hydroxy-isophthalamide moieties within their macrocyclic structure and are characterized by surprisingly low, non-specific binding to a variety of polypeptides such as antibodies and proteins as well as high kinetic stability. These characteristics distinguish them from known, open-structured ligands.

  12. Bioprocessing Reagent Description

    E-print Network

    Lebendiker, Mario

    , and electrophoresis. This protocol describes E. coli lysis with Lysonase Bioprocessing Reagent treatment combined with a freeze/thaw of the cell pellet. Protocols for E. coli lysis using Lysonase with mechanical lysis, Bug for research use only #12;Lysonase TM Bioprocessing Reagent E. Coli Lysis using Freeze/Thaw This protocol

  13. Luminescent lanthanide coordination polymers

    SciTech Connect

    Ma, L.; Evans, O.R.; Foxman, B.M.; Lin, W.

    1999-12-13

    One-dimensional lanthanide coordination polymers with the formula Ln(isonicotinate){sub 3}(H{sub 2}O){sub 2} (Ln = Ce, Pr, Nd, Sm, Eu, Tb; 1a-f) were synthesized by treating nitrate or perchlorate salts of Ln(III) with 4-pyridinecarboxaldehyde under hydro(solvo)thermal conditions. Single-crystal and powder X-ray diffraction studies indicate that these lanthanide coordination polymers adopt two different structures. While Ce(III), Pr(III), and Nd(III) complexes adopt a chain structure with alternating Ln-(carboxylate){sub 2}-Ln and Ln-(carboxylate){sub 4}-Ln linkages, Sm(III), Eu(III), and Tb(III) complexes have a doubly carboxylate-bridged infinite-chain structure with one chelating carboxylate group on each metal center. In both structures, the lanthanide centers also bind to two water molecules to yield an eight-coordinate, square antiprismatic geometry. The pyridine nitrogen atoms of the isonicotinate groups do not coordinate to the metal centers in these lanthanide(III) complexes; instead, they direct the formation of Ln(III) coordination polymers via hydrogen bonding with coordinated water molecules. Photoluminescence measurements show that Tb(isonicotinate){sub 3}(H{sub 2}O){sub 2} is highly emissive at room temperature with a quantum yield of {approximately}90%. These results indicate that highly luminescent lanthanide coordination polymers can be assembled using a combination of coordination and hydrogen bonds. Crystal data for 1a: monoclinic space group P2{sub 1}/c, a = 9.712(2) {angstrom}, b = 19.833(4) {angstrom}, c = 11.616(2) {angstrom}, {beta} = 111.89(3){degree}, Z = 4. Crystal data for 1f: monoclinic space group C2/c, a = 20.253(4) {angstrom}, b = 11.584(2) {angstrom}, c = 9.839(2) {angstrom}, {beta} = 115.64(3){degree}, Z = 8.

  14. Reference Reagents Group

    Cancer.gov

    The goal of our project is the production and distribution of qualified DNA vectors, cell lines, viruses, and proteins, initially as resources for the Frederick National Laboratory for Cancer Research RAS mission and ultimately as high-quality reagents to supply to the larger RAS community. Eventually we hope also to generate reagents specifically requested by the extramural community. Sequence-verified libraries of RAS and RAS-related genes in Gateway combinatorial cloning vectors are available now.

  15. Advancing the scientific basis of trivalent actinide-lanthanide separations

    SciTech Connect

    Nash, K.L. [Washington State University, Department of Chemistry, PO Box 644630, Pullman, WA 99164-4630 (United States)

    2013-07-01

    For advanced fuel cycles designed to support transmutation of transplutonium actinides, several options have been demonstrated for process-scale aqueous separations for U, Np, Pu management and for partitioning of trivalent actinides and fission product lanthanides away from other fission products. The more difficult mutual separation of Am/Cm from La-Tb remains the subject of considerable fundamental and applied research. The chemical separations literature teaches that the most productive alternatives to pursue are those based on ligand donor atoms less electronegative than O, specifically N- and S-containing complexants and chloride ion (Cl{sup -}). These 'soft-donor' atoms have exhibited usable selectivity in their bonding interactions with trivalent actinides relative to lanthanides. In this report, selected features of soft donor reagent design, characterization and application development will be discussed. The roles of thiocyanate, aminopoly-carboxylic acids and lactate in separation processes are detailed. (authors)

  16. Aromatic triamide-lanthanide complexes

    DOEpatents

    2013-10-08

    The present invention provides luminescent lanthanide metal chelates comprising a metal ion of the lanthanide series and a complexing agent comprising at least one phthalamidyl moiety. Also provided are probes incorporating the phthalamidyl ligands of the invention and methods utilizing the ligands of the invention and probes comprising the ligands of the invention.

  17. Tailoring lanthanide nanocrystals for nanomedicine

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Tan, Timothy T. Y.

    2013-02-01

    Lanthanide nanocrystals have demonstrated strong potentials in nanomedicine due to its up-conversion and strong magnetic properties, and low toxicity. This talk will focus on strategies in lanthanide nanostructure tailoring to achieve up-conversion color emission tuning, MRI T1 and T2 contrast tuning, and the use of up-conversion fluorescence in drug delivery and cancer cells ablation.

  18. Reagents, Compositions, Weight Loss

    NSDL National Science Digital Library

    Dexter Perkins

    This is a short experimental study of what happens to aluminum hydroxide, silicic acid, magnesium oxide, and calcium carbonate (or reagents of instructors choice) when they are heated to 110 and 1200 degrees. Students determine the formula and calculate the mole percent and weight percent of each element and oxide in each reagent. They heat the samples and calculate percentage weight loss or gain. Finally, they write a lab report summarizing their results. Be sure to have students save their samples for later use in a lab that introduces X-ray diffraction.

  19. RP-IPC with a lactic acid modified eluent for separation and determination of lanthanide ions

    SciTech Connect

    Vera-Avila, L.E.; Camacho, E. (Analytical Chemistry Dept., Facultad de Quimica, Univ. Nacional Autonoma de Mexico, 04510 D.F. (Mexico))

    1992-01-01

    In this paper, a modified method for the separation and determination of Rare Earth Elements in solution is developed. Lanthanide ions were separated by Reversed-Phase Ion Pair Chromatography using a mobile phase gradient of pH and lactic acid concentration. A post-column reaction with 4-(2 pyridyl)azo resorcinol was carried out for the spectrophotometric detection of solutes. The derivatizing reagent composition was optimized for good solute sensitivity and long-term reagent stability. Method limitations due to inadequate instrumentation are presented and discussed.

  20. Use of soft heterocyclic N-donor ligands to separate actinides and lanthanides.

    PubMed

    Hudson, Michael J; Harwood, Laurence M; Laventine, Dominic M; Lewis, Frank W

    2013-04-01

    The removal of the most long-lived radiotoxic elements from used nuclear fuel, minor actinides, is foreseen as an essential step toward increasing the public acceptance of nuclear energy as a key component of a low-carbon energy future. Once removed from the remaining used fuel, these elements can be used as fuel in their own right in fast reactors or converted into shorter-lived or stable elements by transmutation prior to geological disposal. The SANEX process is proposed to carry out this selective separation by solvent extraction. Recent efforts to develop reagents capable of separating the radioactive minor actinides from lanthanides as part of a future strategy for the management and reprocessing of used nuclear fuel are reviewed. The current strategies for the reprocessing of PUREX raffinate are summarized, and some guiding principles for the design of actinide-selective reagents are defined. The development and testing of different classes of solvent extraction reagent are then summarized, covering some of the earliest ligand designs right through to the current reagents of choice, bis(1,2,4-triazine) ligands. Finally, we summarize research aimed at developing a fundamental understanding of the underlying reasons for the excellent extraction capabilities and high actinide/lanthanide selectivities shown by this class of ligands and our recent efforts to immobilize these reagents onto solid phases. PMID:22867058

  1. Trivalent Actinide and Lanthanide Separations by Dialkyl?Substituted Diphosphonic Acids

    Microsoft Academic Search

    R. Chiarizia; D. R. McAlister; A. W. Herlinger

    2005-01-01

    The dialkyl?substituted diphosphonic acids are powerful solvent extraction reagents for actinide separation and preconcentration from biological, environmental, and nuclear waste samples. In spite of the intensive scrutiny of the solvent extraction properties of these compounds, only the extraction of Eu(III) and Am(III), among the lanthanides and trivalent actinides, has been investigated thus far. In this work, we report the extraction

  2. Tropomyosin isoforms and reagents

    PubMed Central

    Schevzov, Galina; Whittaker, Shane P; Fath, Thomas; Lin, Jim JC

    2011-01-01

    Tropomyosins are rod-like dimers which form head-to-tail polymers along the length of actin filaments and regulate the access of actin binding proteins to the filaments.1 The diversity of tropomyosin isoforms, over 40 in mammals, and their role in an increasing number of biological processes presents a challenge both to experienced researchers and those new to this field. The increased appreciation that the role of these isoforms expands beyond that of simply stabilizing actin filaments has lead to a surge of reagents and techniques to study their function and mechanisms of action. This report is designed to provide a basic guide to the genes and proteins and the availability of reagents which allow effective study of this family of proteins. We highlight the value of combining multiple techniques to better evaluate the function of different tm isoforms and discuss the limitations of selected reagents. Brief background material is included to demystify some of the unfortunate complexity regarding this multi-gene family of proteins including the unconventional nomenclature of the isoforms and the evolutionary relationships of isoforms between species. Additionally, we present step-by-step detailed experimental protocols used in our laboratory to assist new comers to the field and experts alike. PMID:22069507

  3. Luminescent Lanthanide Reporters for High-Sensitivity Novel Bioassays.

    SciTech Connect

    Anstey, Mitchell; Fruetel, Julia A.; Foster, Michael E.; Hayden, Carl C.; Buckley, Heather L.; Arnold, John

    2013-09-01

    Biological imaging and assay technologies rely on fluorescent organic dyes as reporters for a number of interesting targets and processes. However, limitations of organic dyes such as small Stokes shifts, spectral overlap of emission signals with native biological fluorescence background, and photobleaching have all inhibited the development of highly sensitive assays. To overcome the limitations of organic dyes for bioassays, we propose to develop lanthanide-based luminescent dyes and demonstrate them for molecular reporting applications. This relatively new family of dyes was selected for their attractive spectral and chemical properties. Luminescence is imparted by the lanthanide atom and allows for relatively simple chemical structures that can be tailored to the application. The photophysical properties offer unique features such as narrow and non-overlapping emission bands, long luminescent lifetimes, and long wavelength emission, which enable significant sensitivity improvements over organic dyes through spectral and temporal gating of the luminescent signal.Growth in this field has been hindered due to the necessary advanced synthetic chemistry techniques and access to experts in biological assay development. Our strategy for the development of a new lanthanide-based fluorescent reporter system is based on chelation of the lanthanide metal center using absorbing chromophores. Our first strategy involves %22Click%22 chemistry to develop 3-fold symmetric chelators and the other involves use of a new class of tetrapyrrole ligands called corroles. This two-pronged approach is geared towards the optimization of chromophores to enhance light output.

  4. Calibration beads containing luminescent lanthanide ion complexes

    EPA Science Inventory

    The reliability of lanthanide luminescence measurements, by both flow cytometry and digital microscopy, will be enhanced by the availability of narrow-band emitting lanthanide calibration beads. These beads can also be used to characterize spectrographic instruments, including mi...

  5. Magnetic susceptibility tensor anisotropies for a lanthanide ion series in a fixed protein matrix.

    PubMed

    Bertini, I; Janik, M B; Lee, Y M; Luchinat, C; Rosato, A

    2001-05-01

    The full series of lanthanide ions (except the radioactive promethium and the S-state gadolinium) has been incorporated into the C-terminal calcium binding site of the dicalcium protein calbindin D(9k). A fairly constant coordination environment is maintained throughout the series. At variance with several lanthanide complexes with small chelating ligands investigated in the past, the large protein moiety provides a large number of NMR signals whose hyperfine shifts can be exclusively ascribed to pseudocontact shifts (PCS). The chemical shifts of 1H and 15N backbone and side chain amide NH groups were accurately measured through HSQC experiments. 1097 PCS were estimated from these by subtracting the diamagnetic contributions measured on HSQC spectra of either the 4f(0) lanthanum(III) or the 4f(14) lutetium(III) derivatives and used to define a quality factor for the structure. The differences in diamagnetic chemical shifts between the two diamagnetic blanks were relatively small, although some were not negligible especially for the nuclei closest to the metal center. These differences were used as a tolerance for the PCS. The magnetic susceptibility tensor anisotropies for each paramagnetic lanthanide ion were obtained as the result of the solution structure determination performed by using the NOEs of the cerium(III) derivative and the PCS of all lanthanides simultaneously. This set of reliable magnetic data permits an experimental assessment of Bleaney's theory relative to the magnetic properties for an extended series of lanthanide complexes in solution. All of the obtained tensors show some rhombicity, as could be expected from the lack of symmetry of the protein environment. The directions of the largest magnetic susceptibility component for Ce, Pr, Nd, Sm, Tb, Dy, and Ho and of the smallest magnetic susceptibility component for Eu, Er, Tm, and Yb were found to be all within 15 degrees from their average (within 20 degrees for Sm), confirming the essential similarity of the coordination environment for all lanthanides. Bleaney's theory is in excellent qualitative agreement with the observed pattern of axial anisotropies. Its quantitative agreement is substantially better than that suggested by previous analyses performed on more limited sets of PCS data for small lanthanide complexes, the so-called crystal field parameter varying only within +/-30% from one lanthanide to another. These variations are even smaller (+/-15%) if a reasonable T(-3) correction is taken into consideration. A knowledge of magnetic susceptibility anisotropy properties of lanthanides is essential in determining the self-orienting properties of lanthanide complexes in solution when immersed in magnetic fields. PMID:11457182

  6. Review: Increasing the Luminescence of Lanthanide Complexes

    Microsoft Academic Search

    Robert C. Leif; Lidia M. Vallarino; Margie C. Becker

    This review compares the chemical and physical properties of lanthanide ion complexes and of other narrow-emitting species that can be used as labels for cytometry. A series of luminescent lanthanide ion macrocyclic complexes, Quantum Dyes®, which do not release or exchange their central lanthanide ion, do accept energy transfer from ligands, and are capable of covalent binding to macromolecules, including

  7. Actinide Lanthanide Separation Process – ALSEP

    SciTech Connect

    Gelis, Artem V.; Lumetta, Gregg J.

    2014-01-29

    Separation of the minor actinides (Am, Cm) from the lanthanides at an industrial scale remains a significant technical challenge for closing the nuclear fuel cycle. To increase the safety of used nuclear fuel (UNF) reprocessing, as well as reduce associated costs, a novel solvent extraction process has been developed. The process allows for partitioning minor actinides, lanthanides and fission products following uranium/plutonium/neptunium removal; minimizing the number of separation steps, flowsheets, chemical consumption, and waste. This new process, Actinide Lanthanide SEParation (ALSEP), uses an organic solvent consisting of a neutral diglycolamide extractant, either N,N,N',N'-tetra(2 ethylhexyl)diglycolamide (T2EHDGA) or N,N,N',N'-tetraoctyldiglycolamide (TODGA), and an acidic extractant 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]), dissolved in an aliphatic diluent (e.g. n-dodecane). The An/Ln co-extraction is conducted from moderate-to-strong nitric acid, while the selective stripping of the minor actinides from the lanthanides is carried out using a polyaminocarboxylic acid/citrate buffered solution at pH anywhere between 3 and 4.5. The extraction and separation of the actinides from the fission products is very effective in a wide range of HNO3 concentrations and the minimum separation factors for lanthanide/Am exceed 30 for Nd/Am, reaching > 60 for Eu/Am under some conditions. The experimental results presented here demonstrate the great potential for a combined system, consisting of a neutral extractant such as T2EHDGA or TODGA, and an acidic extractant such as HEH[EHP], for separating the minor actinides from the lanthanides.

  8. New versatile staining reagents for biological transmission electron microscopy that substitute for uranyl acetate.

    PubMed

    Nakakoshi, Masamichi; Nishioka, Hideo; Katayama, Eisaku

    2011-12-01

    Aqueous uranyl acetate has been extensively used as a superb staining reagent for transmission electron microscopy of biological materials. However, recent regulation of nuclear fuel material severely restricts its use even for purely scientific purposes. Since uranyl salts are hazardous due to biological toxicity and remaining radioactivity, development of safe and non-radioactive substitutes is greatly anticipated. We examined two lanthanide salts, samarium triacetate and gadolinium triacetate, and found that 1-10% solution of these reagents was safe but still possess excellent capability for staining thin sections of plastic-embedded materials of animal and plant origin. Although post-fixation with osmium tetroxide was essential for high-contrast staining, post-staining with lead citrate could be eliminated if a slow-scan CCD camera is available for observation. These lanthanide salts can also be utilized as good negative-staining reagents to study supramolecular architecture of biological macromolecules. They were not as effective as a fixative of protein assembly, reflecting the non-hazardous nature of the reagents. PMID:22146677

  9. Volatile chemical reagent detector

    DOEpatents

    Chen, Liaohai; McBranch, Duncan; Wang, Rong; Whitten, David

    2004-08-24

    A device for detecting volatile chemical reagents based on fluorescence quenching analysis that is capable of detecting neutral electron acceptor molecules. The device includes a fluorescent material, a contact region, a light source, and an optical detector. The fluorescent material includes at least one polymer-surfactant complex. The polymer-surfactant complex is formed by combining a fluorescent ionic conjugated polymer with an oppositely charged surfactant. The polymer-surfactant complex may be formed in a polar solvent and included in the fluorescent material as a solution. Alternatively, the complex may be included in the fluorescent material as a thin film. The use of a polymer-surfactant complex in the fluorescent material allows the device to detect both neutral and ionic acceptor molecules. The use of a polymer-surfactant complex film allows the device and the fluorescent material to be reusable after exposing the fluorescent material to a vacuum for limited time.

  10. US Veterinary Immune Reagents Network

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A major obstacle to advances in veterinary immunology and disease control is the lack of sufficient immunological reagents specific for ruminants, swine, poultry, equine, and aquaculture species. Sets of reagents, i.e. monoclonal (mAb) and polyclonal antibodies (Ab), that can identify the major leu...

  11. US Veterinary Immune Reagents Network

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A major obstacle to advances in veterinary immunology and disease control is the lack of sufficient immunological reagents specific for ruminants, swine, poultry, equine and aquaculture species". Sets of reagents, i.e., monoclonal (mAb) and polyclonal antibodies, that can identify the major leukocy...

  12. 21 CFR 866.3200 - Echinococcus spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 2010-04-01 false Echinococcus spp. serological reagents. 866.3200 ...Reagents § 866.3200 Echinococcus spp. serological reagents. (a) Identification. Echinococcus spp. serological reagents are devices...

  13. LANTHANIDE ENHANCE LUMINESCENCE (LEL) WITH ONE AND TWO PHOTON EXCITATION OF QUANTUM DYES LANTHANIDE (III) - MACROCYCLES

    EPA Science Inventory

    Title: Lanthanide Enhance Luminescence (LEL) with one and two photon excitation of Quantum Dyes? Lanthanide(III)-Macrocycles Principal Author: Robert C. Leif, Newport Instruments Secondary Authors: Margie C. Becker, Phoenix Flow Systems Al Bromm, Virginia Commonw...

  14. 21 CFR 866.4100 - Complement reagent.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents § 866.4100 Complement reagent. (a)...

  15. 21 CFR 866.4100 - Complement reagent.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents § 866.4100 Complement reagent. (a)...

  16. 21 CFR 866.4100 - Complement reagent.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents § 866.4100 Complement reagent. (a)...

  17. 21 CFR 866.4100 - Complement reagent.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents § 866.4100 Complement reagent. (a)...

  18. 21 CFR 866.4100 - Complement reagent.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents § 866.4100 Complement reagent. (a)...

  19. Taking advantage of luminescent lanthanide ions

    Microsoft Academic Search

    Jean-Claude G. Bunzli; Claude Piguet

    2005-01-01

    Lanthanide ions possess fascinating optical properties and their discovery, first industrial uses and present high technological applications are largely governed by their interaction with light. Lighting devices (economical luminescent lamps, light emitting diodes), television and computer displays, optical fibres, optical amplifiers, lasers, as well as responsive luminescent stains for biomedical analysis, medical diagnosis, and cell imaging rely heavily on lanthanide

  20. ITP of lanthanides in microfluidic PMMA chip.

    PubMed

    Cong, Yongzheng; Bottenus, Danny; Liu, Bingwen; Clark, Sue B; Ivory, Cornelius F

    2014-03-01

    An ITP separation of eight lanthanides on a serpentine PMMA microchip with a tee junction and a 230-mm-long serpentine channel is described. The cover of the PMMA chip is 175 ?m thick so that a C(4) D in microchip mode can be used to detect the lanthanides as they migrate through the microchannel. Acetate and ?-hydroxyisobutyric acid are used as complexing agents to increase the electrophoretic mobility difference between the lanthanides. Eight lanthanides are concentrated within ? 6 min by ITP in the microchip using 10 mM ammonium acetate at pH 4.5 as the leading electrolyte and 10 mM acetic acid at ? pH 3.0 as the terminating electrolyte. In addition, a 2D numerical simulation of the lanthanides undergoing ITP in the microchip is compared with experimental results using COMSOL Multiphysics v4.3a. PMID:24258617

  1. Enantioselective catalysis using lanthanide Schiff base complexes

    SciTech Connect

    Watkin, J.G. [Los Alamos National Laboratory, NM (United States)

    1996-10-01

    The use of lanthanide-based catalysts to facilitate organic transformations is currently an area of rapid growth, in particular the application of lanthanide alkoxide and triflate derivatives as effective Lewis-acidic catalysts for Michael additions and aldol reactions, and bis-pentamethylcyclopentadienyl derivatives as extremely active catalysts for hydrogenation and enantioselective hydroamination reactions. We have begun an investigation into the use of lanthanide complexes containing chiral alkoxide ligands as Lewis-acidic catalysts for enantioselective organic reactions. Since the large ionic radii of the lanthanide +III metal centers can often lead to oligomerization of simple alkoxide species, we have also examined the use of multidentate, chelating Schiff base ligands to provide an asymmetric environment about a lanthanide metal center. Structural investigations of the catalysts will be described, together with the use of these catalysts in enantioselective Meerwein-Ponndorf-Verley reduction of ketones and nitroaldol reactions.

  2. Chemical Amplification with Encapsulated Reagents

    NASA Technical Reports Server (NTRS)

    Chen, Jian; Koemer, Steffi; Craig, Stephen; Lin, Shirley; Rudkevich, Dmitry M.; Rebek, Julius, Jr.

    2002-01-01

    Autocatalysis and chemical amplification are characteristic properties of living systems, and they give rise to behaviors such as increased sensitivity, responsiveness, and self-replication. Here we report a synthetic system in which a unique form of compartmentalization leads to nonlinear, autocatalytic behavior. The compartment is a reversibly formed capsule in which a reagent is sequestered. Reaction products displace the reagent from the capsule into solution and the reaction rate is accelerated. The resulting self-regulation is sensitive to the highly selective molecular recognition properties of the capsule.

  3. Exploring Crown Ethers as Shift Reagents for Ion Mobility Spectrometry

    E-print Network

    Clemmer, David E.

    .; Valentine, S. J.; Counterman, A. E.; Clemmer, D. E. Anal. Chem. 1999, 71, 291-301. (2) Valentine, S. J.; Schultz, A. J. Anal. Chem. 2000, 72, 3965-3971. (5) Wu, C.; Siems, W. F.; Klasmeier, J.; Hill, H. H., Jr. Anal. Chem. 2000, 72, 391. (6) Guevremont, R.; Barnett, D. A.; Purves, R. W.; Vandermey, J. Anal. Chem

  4. Separation of actinides from lanthanides

    DOEpatents

    Smith, B.F.; Jarvinen, G.D.; Ryan, R.R.

    1988-03-31

    An organic extracting solution and an extraction method useful for separating elements of the actinide series of the periodic table from elements of the lanthanide series, where both are in trivalent form is described. The extracting solution consists of a primary ligand and a secondary ligand, preferably in an organic solvent. The primary ligand is a substituted monothio-1,3-dicarbonyl, which includes a substituted 4-acyl-2-pyrazolin-5-thione, such as 4-benzoyl-2,4- dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione (BMPPT). The secondary ligand is a substituted phosphine oxide, such as trioctylphosphine oxide (TOPO).

  5. Separation of actinides from lanthanides

    DOEpatents

    Smith, Barbara F. (Los Alamos, NM); Jarvinen, Gordon D. (Los Alamos, NM); Ryan, Robert R. (Los Alamos, NM)

    1989-01-01

    An organic extracting solution and an extraction method useful for separating elements of the actinide series of the periodic table from elements of the lanthanide series, where both are in trivalent form. The extracting solution consists of a primary ligand and a secondary ligand, preferably in an organic solvent. The primary ligand is a substituted monothio-1,3-dicarbonyl, which includes a substituted 4-acyl-2-pyrazolin-5-thione, such as 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione (BMPPT). The secondary ligand is a substituted phosphine oxide, such as trioctylphosphine oxide (TOPO).

  6. Synthesis of N-Fmoc-(2S,3S,4R)-3,4-dimethylglutamine. An Application of Lanthanide-Catalyzed Transamidation

    PubMed Central

    Çalimsiz, Selçuk; Lipton, Mark A.

    2006-01-01

    N-Fmoc-(2S,3S,4R)-3,4-dimethylglutamine (6) was synthesized from t-butyl N-Boc-(2S,3S,4R)-dimethylpyroglutamate (13). This synthesis involved selective deprotection of a Boc group from a lactam nitrogen in the presence of a t-butyl ester, Fmoc protection of the lactam, and a lanthanide-catalyzed transamidation reaction of the Fmoc-protected lactam using ammonia and dimethylaluminum chloride. The scope of Lewis acid-catalyzed transamidation of acylated lactams was explored through the variation of lanthanide, lactam, acyl group, amine and aluminum reagent. The reactivity of various metal triflates was found to vary in the qualitative order: Yb?Sc>Er?Eu?Sm>Ce?AgI>CuII?Zn. Intriguingly, catalysis was only observed when ammonia was the nitrogen nucleophile; addition of other amidoaluminum complexes to acyl lactams was found to be insensitive to the addition of lanthanides. PMID:16050680

  7. 21 CFR 866.3360 - Lymphocytic choriomeningitis virus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... false Lymphocytic choriomeningitis virus serological reagents. 866.3360 Section...866.3360 Lymphocytic choriomeningitis virus serological reagents. (a) Identification. Lymphocytic choriomeningitis virus serological reagents are devices...

  8. 21 CFR 866.3360 - Lymphocytic choriomeningitis virus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... false Lymphocytic choriomeningitis virus serological reagents. 866.3360 Section...866.3360 Lymphocytic choriomeningitis virus serological reagents. (a) Identification. Lymphocytic choriomeningitis virus serological reagents are devices...

  9. 21 CFR 866.3360 - Lymphocytic choriomeningitis virus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... false Lymphocytic choriomeningitis virus serological reagents. 866.3360 Section...866.3360 Lymphocytic choriomeningitis virus serological reagents. (a) Identification. Lymphocytic choriomeningitis virus serological reagents are devices...

  10. 21 CFR 866.3240 - Equine encephalomyelitis virus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Equine encephalomyelitis virus serological reagents. 866.3240...866.3240 Equine encephalomyelitis virus serological reagents. (a) Identification. Equine encephalomyelitis virus serological reagents are...

  11. 21 CFR 866.3240 - Equine encephalomyelitis virus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Equine encephalomyelitis virus serological reagents. 866.3240...866.3240 Equine encephalomyelitis virus serological reagents. (a) Identification. Equine encephalomyelitis virus serological reagents are...

  12. 21 CFR 866.3360 - Lymphocytic choriomeningitis virus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... false Lymphocytic choriomeningitis virus serological reagents. 866.3360 Section...866.3360 Lymphocytic choriomeningitis virus serological reagents. (a) Identification. Lymphocytic choriomeningitis virus serological reagents are devices...

  13. 21 CFR 866.3240 - Equine encephalomyelitis virus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Equine encephalomyelitis virus serological reagents. 866.3240...866.3240 Equine encephalomyelitis virus serological reagents. (a) Identification. Equine encephalomyelitis virus serological reagents are...

  14. 21 CFR 866.3240 - Equine encephalomyelitis virus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Equine encephalomyelitis virus serological reagents. 866.3240...866.3240 Equine encephalomyelitis virus serological reagents. (a) Identification. Equine encephalomyelitis virus serological reagents are...

  15. 21 CFR 866.3740 - Streptococcus spp. serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Streptococcus spp. serological reagents. 866...Serological Reagents § 866.3740 Streptococcus spp. serological reagents. (a) Identification. Streptococcus spp. serological...

  16. 21 CFR 866.3740 - Streptococcus spp. serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Streptococcus spp. serological reagents. 866...Serological Reagents § 866.3740 Streptococcus spp. serological reagents. (a) Identification. Streptococcus spp. serological...

  17. 21 CFR 866.3740 - Streptococcus spp. serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Streptococcus spp. serological reagents. 866...Serological Reagents § 866.3740 Streptococcus spp. serological reagents. (a) Identification. Streptococcus spp. serological...

  18. 21 CFR 866.3740 - Streptococcus spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Streptococcus spp. serological reagents. 866...Serological Reagents § 866.3740 Streptococcus spp. serological reagents. (a) Identification. Streptococcus spp. serological...

  19. 21 CFR 866.3700 - Staphylococcus aureus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Staphylococcus aureus serological reagents...Serological Reagents § 866.3700 Staphylococcus aureus serological reagents. (a) Identification. Staphylococcus aureus serological...

  20. 21 CFR 866.3700 - Staphylococcus aureus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Staphylococcus aureus serological reagents...Serological Reagents § 866.3700 Staphylococcus aureus serological reagents. (a) Identification. Staphylococcus aureus serological...

  1. 21 CFR 866.3700 - Staphylococcus aureus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Staphylococcus aureus serological reagents...Serological Reagents § 866.3700 Staphylococcus aureus serological reagents. (a) Identification. Staphylococcus aureus serological...

  2. 21 CFR 866.3700 - Staphylococcus aureus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Staphylococcus aureus serological reagents...Serological Reagents § 866.3700 Staphylococcus aureus serological reagents. (a) Identification. Staphylococcus aureus serological...

  3. Rapid Separation of Beryllium and Lanthanide Derivatives by Capillary Gas Chromatography

    SciTech Connect

    Harvey, Scott D.; Lucke, Richard B.; Douglas, Matthew

    2012-10-01

    Previous studies describe derivatization of metal ions followed by analysis using gas chromatography, usually on packed columns. In many of these studies, stable and volatile derivatives were formed using fluorinated ?-diketonate reagents. This paper extends previous work by investigating separations of the derivatives on small-diameter capillary gas chromatography columns and exploring on-fiber, solid-phase microextraction derivatization techniques for beryllium. The ?-diketonate used for these studies was 1,1,1,2,2,6,6,7,7,7-decafluoro-3,5-heptanedione. Derivatization of lanthanides also required addition of a neutral donor, dibutyl sulfoxide, in addition to 1,1,1,2,2,6,6,7,7,7-decafluoro-3,5-heptanedione. Un-optimized separations on a 100-µm i.d. capillary column proved capable of rapid separations (within 15 min) of lanthanide derivatives that are adjacent to one another in the periodic table. Full-scan mass spectra were obtained from derivatives containing 5 ng of each lanthanide. Studies also developed a simple on-fiber solid-phase microextraction derivatization of beryllium. Beryllium could be analyzed in the presence of other alkali earth elements [Ba(II) and Sr(II)] without interference. Extension of the general approach was demonstrated for several additional elements [i.e., Cu(II), Cr(III), and Ga(III)].

  4. Colour Reagent for Paper Chromatography of Steroids

    Microsoft Academic Search

    A. Bodánszky; J. Kollonitsch

    1955-01-01

    FOR the paper chromatography of steroids several colour reagents are used, such as 2,4-dinitrophenyl-hydrazine, Zimmermann's reagent, phosphomolybdic acid, antimony trichloride, etc. Their common defect is that the reagent gives some colour with the paper itself, and so the contrast between spot and paper is too small. We have found that acid aniline phthalate in alcoholic solution-the reagent Partridge used for

  5. The role of lanthanides in optical materials

    SciTech Connect

    Weber, M.J.

    1995-05-01

    A survey is presented of the use of the lanthanides as chemical components in transmitting optical materials and as activators in materials for luminescent, electro-optic, magneto-optic, and various photosensitive applications.

  6. Lanthanide-tagged proteins – An illuminating partnership

    E-print Network

    Imperiali, Barbara

    Lanthanide-tagged proteins are valuable for exploiting the unique properties of Ln ions for investigating protein structure, function, and dynamics. Introduction of the Ln into the target is accomplished via chemical ...

  7. The Explosive Potential of Tollens' Reagent.

    ERIC Educational Resources Information Center

    Breedlove, C. H.; Softy, John

    1983-01-01

    Reports on an explosion that occurred using Tollens' reagent, emphasizing that students should prepare the reagent immediately before use and discard it immediately after use by flushing it down the drain. States that under no conditions should Tollens' reagent be stored. (Author/JN)

  8. Hypervalent Iodine Reagents in Organic Synthesis

    E-print Network

    Johnson, Jeff S.

    Hypervalent Iodine Reagents in Organic Synthesis Andrew T. Parsons March 23, 2007 #12;Outline · Background · Iodine(III) reagents · Iodine(V) reagents · Conclusions #12;Hypervalent Iodine: An Introduction Zhdankin, V. V.; Stang, P. J. Chem. Rev. 2002, 102, 2523-2584. · Hypervalent iodine: Species that exceed

  9. Energy transfer in lanthanide upconversion studies for extended optical applications.

    PubMed

    Dong, Hao; Sun, Ling-Dong; Yan, Chun-Hua

    2015-03-10

    Lanthanide pairs, which can upconvert low energy photons into higher energy photons, are promising for efficient upconversion emission. A typical system with Yb(3+) as a sensitizer can convert short NIR into visible/ultraviolet light via energy transfer between lanthanide ions. Such upconverting nanocrystals doped with lanthanide ions have found significant potential in bioimaging, photochemical reactions and energy conversion. This review presents a fundamental understanding of energy transfer in lanthanide-supported photon upconversion. We introduce the emerging progress in excitation selection based on the energy transfer within lanthanide ions or activation from antennae, with an outlook in the development and applications of the lanthanide upconversion emissions. PMID:25242465

  10. Bond-valence parameters of lanthanides.

    PubMed

    Trzesowska, Agata; Kruszynski, Rafal; Bartczak, Tadeusz J

    2006-10-01

    Ln-O and Ln-N bond-valence parameters have been computed in coordination complexes for lanthanides (Ln) at oxidation states other than +3 (Ce(IV), Sm(II), Eu(II) and Yb(II)). Moreover, Ln-Cl, Ln-S and Ln-C(pi-bonded) bond-valence parameters are presented, as calculated for coordination compounds. In general, the bond-valence parameters decrease in the order Ln-O > Ln-C > Ln-N > Ln-Cl > Ln-S. It has been found that the values of bond-valence parameters decrease with increasing lanthanide atomic number for coordination compounds. As expected, the values of lanthanide-oxygen and lanthanide-nitrogen bond-valence parameters diminish with increasing lanthanide oxidation state. Several examples are given where the total valence of the lanthanide ion is apparently incorrectly assigned, as well as cases where bond-valence method calculations confirm the doubtful oxidation state assignment. PMID:16983155

  11. 21 CFR 866.3400 - Parainfluenza virus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 2012-04-01 false Parainfluenza virus serological reagents. 866.3400 Section...Reagents § 866.3400 Parainfluenza virus serological reagents. (a) Identification. Parainfluenza virus serological reagents are devices...

  12. 21 CFR 866.3940 - West Nile virus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false West Nile virus serological reagents. 866.3940 ...Serological Reagents § 866.3940 West Nile virus serological reagents. (a) Identification. West Nile virus serological reagents are devices...

  13. 21 CFR 866.3380 - Mumps virus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Mumps virus serological reagents. 866.3380 Section...Serological Reagents § 866.3380 Mumps virus serological reagents. (a) Identification. Mumps virus serological reagents consist of...

  14. 21 CFR 866.3400 - Parainfluenza virus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 2013-04-01 false Parainfluenza virus serological reagents. 866.3400 Section...Reagents § 866.3400 Parainfluenza virus serological reagents. (a) Identification. Parainfluenza virus serological reagents are devices...

  15. 21 CFR 866.3380 - Mumps virus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Mumps virus serological reagents. 866.3380 Section...Serological Reagents § 866.3380 Mumps virus serological reagents. (a) Identification. Mumps virus serological reagents consist of...

  16. 21 CFR 866.3380 - Mumps virus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Mumps virus serological reagents. 866.3380 Section...Serological Reagents § 866.3380 Mumps virus serological reagents. (a) Identification. Mumps virus serological reagents consist of...

  17. 21 CFR 866.3336 - John Cunningham Virus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false John Cunningham Virus serological reagents. 866.3336 ...Reagents § 866.3336 John Cunningham Virus serological reagents. (a) Identification. John Cunningham Virus serological reagents are devices...

  18. 21 CFR 866.3940 - West Nile virus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false West Nile virus serological reagents. 866.3940 ...Serological Reagents § 866.3940 West Nile virus serological reagents. (a) Identification. West Nile virus serological reagents are devices...

  19. 21 CFR 866.3380 - Mumps virus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Mumps virus serological reagents. 866.3380 Section...Serological Reagents § 866.3380 Mumps virus serological reagents. (a) Identification. Mumps virus serological reagents consist of...

  20. 21 CFR 866.3330 - Influenza virus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Influenza virus serological reagents. 866.3330 ...Serological Reagents § 866.3330 Influenza virus serological reagents. (a) Identification. Influenza virus serological reagents are...

  1. 21 CFR 866.3400 - Parainfluenza virus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 2014-04-01 false Parainfluenza virus serological reagents. 866.3400 Section...Reagents § 866.3400 Parainfluenza virus serological reagents. (a) Identification. Parainfluenza virus serological reagents are devices...

  2. 21 CFR 866.3400 - Parainfluenza virus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 2011-04-01 false Parainfluenza virus serological reagents. 866.3400 Section...Reagents § 866.3400 Parainfluenza virus serological reagents. (a) Identification. Parainfluenza virus serological reagents are devices...

  3. 21 CFR 866.3940 - West Nile virus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false West Nile virus serological reagents. 866.3940 ...Serological Reagents § 866.3940 West Nile virus serological reagents. (a) Identification. West Nile virus serological reagents are devices...

  4. 21 CFR 866.3330 - Influenza virus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Influenza virus serological reagents. 866.3330 ...Serological Reagents § 866.3330 Influenza virus serological reagents. (a) Identification. Influenza virus serological reagents are...

  5. 21 CFR 866.3330 - Influenza virus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Influenza virus serological reagents. 866.3330 ...Serological Reagents § 866.3330 Influenza virus serological reagents. (a) Identification. Influenza virus serological reagents are...

  6. 21 CFR 866.3940 - West Nile virus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false West Nile virus serological reagents. 866.3940 ...Serological Reagents § 866.3940 West Nile virus serological reagents. (a) Identification. West Nile virus serological reagents are devices...

  7. 21 CFR 866.3330 - Influenza virus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Influenza virus serological reagents. 866.3330 ...Serological Reagents § 866.3330 Influenza virus serological reagents. (a) Identification. Influenza virus serological reagents are...

  8. 21 CFR 866.3380 - Mumps virus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Mumps virus serological reagents. 866.3380 Section...Serological Reagents § 866.3380 Mumps virus serological reagents. (a) Identification. Mumps virus serological reagents consist of...

  9. 21 CFR 866.3940 - West Nile virus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false West Nile virus serological reagents. 866.3940 ...Serological Reagents § 866.3940 West Nile virus serological reagents. (a) Identification. West Nile virus serological reagents are devices...

  10. 21 CFR 866.3300 - Haemophilus spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Haemophilus spp. serological reagents. 866.3300 ...Reagents § 866.3300 Haemophilus spp. serological reagents. (a) Identification. Haemophilus spp. serological reagents are devices...

  11. 21 CFR 866.3375 - Mycoplasma spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Mycoplasma spp. serological reagents. 866.3375 ...Serological Reagents § 866.3375 Mycoplasma spp. serological reagents. (a) Identification. Mycoplasma spp. serological reagents are devices...

  12. 21 CFR 866.3085 - Brucella spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Brucella spp. serological reagents. 866.3085 ...Serological Reagents § 866.3085 Brucella spp. serological reagents. (a) Identification. Brucella spp. serological reagents are devices...

  13. 21 CFR 866.3550 - Salmonella spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Salmonella spp. serological reagents. 866.3550 ...Serological Reagents § 866.3550 Salmonella spp. serological reagents. (a) Identification. Salmonella spp. serological reagents are devices...

  14. 21 CFR 866.3020 - Adenovirus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Adenovirus serological reagents. 866.3020...Serological Reagents § 866.3020 Adenovirus serological reagents. (a) Identification. Adenovirus serological reagents are devices...

  15. 21 CFR 864.8950 - Russell viper venom reagent.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 2014-04-01 false Russell viper venom reagent. 864.8950 Section 864.8950...Hematology Reagents § 864.8950 Russell viper venom reagent. (a) Identification. Russell viper venom reagent is a device used to determine...

  16. 21 CFR 864.8950 - Russell viper venom reagent.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 2013-04-01 false Russell viper venom reagent. 864.8950 Section 864.8950...Hematology Reagents § 864.8950 Russell viper venom reagent. (a) Identification. Russell viper venom reagent is a device used to determine...

  17. 21 CFR 864.8950 - Russell viper venom reagent.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 2012-04-01 false Russell viper venom reagent. 864.8950 Section 864.8950...Hematology Reagents § 864.8950 Russell viper venom reagent. (a) Identification. Russell viper venom reagent is a device used to determine...

  18. 21 CFR 864.8540 - Red cell lysing reagent.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Red cell lysing reagent. 864.8540 Section 864... Hematology Reagents § 864.8540 Red cell lysing reagent. (a) Identification. A red cell lysing reagent is a device used to...

  19. 21 CFR 864.8540 - Red cell lysing reagent.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Red cell lysing reagent. 864.8540 Section 864... Hematology Reagents § 864.8540 Red cell lysing reagent. (a) Identification. A red cell lysing reagent is a device used to...

  20. 21 CFR 864.8540 - Red cell lysing reagent.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Red cell lysing reagent. 864.8540 Section 864... Hematology Reagents § 864.8540 Red cell lysing reagent. (a) Identification. A red cell lysing reagent is a device used to...

  1. 21 CFR 866.3395 - Norovirus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Norovirus serological reagents. 866.3395...Serological Reagents § 866.3395 Norovirus serological reagents. (a) Identification. Norovirus serological reagents are devices...

  2. 21 CFR 866.3395 - Norovirus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Norovirus serological reagents. 866.3395...Serological Reagents § 866.3395 Norovirus serological reagents. (a) Identification. Norovirus serological reagents are devices...

  3. 21 CFR 864.8540 - Red cell lysing reagent.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 2010-04-01 2010-04-01 false Red cell lysing reagent. 864.8540 Section...DEVICES Hematology Reagents § 864.8540 Red cell lysing reagent. (a) Identification. A red cell lysing reagent is a device used to...

  4. 21 CFR 864.8540 - Red cell lysing reagent.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Red cell lysing reagent. 864.8540 Section 864... Hematology Reagents § 864.8540 Red cell lysing reagent. (a) Identification. A red cell lysing reagent is a device used to...

  5. Selective Separation of Trivalent Actinides from Lanthanides by Aqueous Processing with Introduction of Soft Donor Atoms

    SciTech Connect

    Kenneth L. Nash

    2009-09-22

    Implementation of a closed loop nuclear fuel cycle requires the utilization of Pu-containing MOX fuels with the important side effect of increased production of the transplutonium actinides, most importantly isotopes of Am and Cm. Because the presence of these isotopes significantly impacts the long-term radiotoxicity of high level waste, it is important that effective methods for their isolation and/or transmutation be developed. Furthermore, since transmutation is most efficiently done in the absence of lanthanide fission products (high yield species with large thermal neutron absorption cross sections) it is important to have efficient procedures for the mutual separation of Am and Cm from the lanthanides. The chemistries of these elements are nearly identical, differing only in the slightly stronger strength of interaction of trivalent actinides with ligand donor atoms softer than O (N, Cl-, S). Research being conducted around the world has led to the development of new reagents and processes with considerable potential for this task. However, pilot scale testing of these reagents and processes has demonstrated the susceptibility of the new classes of reagents to radiolytic and hydrolytic degradation. In this project, separations of trivalent actinides from fission product lanthanides have been investigated in studies of 1) the extraction and chemical stability properties of a class of soft-donor extractants that are adapted from water-soluble analogs, 2) the application of water soluble soft-donor complexing agents in tandem with conventional extractant molecules emphasizing fundamental studies of the TALSPEAK Process. This research was conducted principally in radiochemistry laboratories at Washington State University. Collaborators at the Radiological Processing Laboratory (RPL) at the Pacific Northwest National Laboratory (PNNL) have contributed their unique facilities and capabilities, and have supported student internships at PNNL to broaden their academic experience. New information has been developed to qualify the extraction potential of a class of pyridine-functionalized tetraaza complexants indicating potential single contact Am-Nd separation factors of about 40. The methodology developed for characterization will find further application in our continuing efforts to synthesize and characterize new reagents for this separation. Significant new insights into the performance envelope and supporting information on the TALSPEAK process has also been developed.

  6. Lanthanide-doped upconversion nano-bioprobes: electronic structures, optical properties, and biodetection.

    PubMed

    Zheng, Wei; Huang, Ping; Tu, Datao; Ma, En; Zhu, Haomiao; Chen, Xueyuan

    2015-03-10

    Lanthanide-doped upconversion nanoparticles (UCNPs) have attracted considerable interest due to their superior physicochemical features, such as large anti-Stokes shifts, low autofluorescence background, low toxicity and high penetration depth, which make them extremely suitable for use as alternatives to conventional downshifting luminescence bioprobes like organic dyes and quantum dots for various biological applications. A fundamental understanding of the photophysics of lanthanide-doped UCNPs is of vital importance for discovering novel optical properties and exploring their new applications. In this review, we focus on the most recent advances in the development of lanthanide-doped UCNPs as potential luminescent nano-bioprobes by means of our customized lanthanide photophysics measurement platforms specially designed for upconversion luminescence, which covers from their fundamental photophysics to bioapplications, including electronic structures (energy levels and local site symmetry of emitters), excited-state dynamics, optical property designing, and their promising applications for in vitro biodetection of tumor markers. Some future prospects and efforts towards this rapidly growing field are also envisioned. PMID:25093303

  7. Renewable-reagent electrochemical sensor

    DOEpatents

    Wang, Joseph (Las Cruces, NM); Olsen, Khris B. (Richland, WA)

    1999-01-01

    A new electrochemical probe(s) design allowing for continuous (renewable) reagent delivery. The probe comprises an integrated membrane-sampling/electrochemical sensor that prevents interferences from surface-active materials and greatly extends the linear range. The probe(s) is useful for remote or laboratory-based monitoring in connection with microdialysis sampling and electrochemical measurements of metals and organic compounds that are not readily detected in the absence of reacting with the compound. Also disclosed is a method of using the probe(s).

  8. Renewable-reagent electrochemical sensor

    DOEpatents

    Wang, J.; Olsen, K.B.

    1999-08-24

    A new electrochemical probe(s) design allowing for continuous (renewable) reagent delivery is described. The probe comprises an integrated membrane sampling/electrochemical sensor that prevents interferences from surface-active materials and greatly extends the linear range. The probe(s) is useful for remote or laboratory-based monitoring in connection with microdialysis sampling and electrochemical measurements of metals and organic compounds that are not readily detected in the absence of reacting with the compound. Also disclosed is a method of using the probe(s). 19 figs.

  9. The catalytic domain of MMP-1 studied through tagged lanthanides.

    PubMed

    Bertini, Ivano; Calderone, Vito; Cerofolini, Linda; Fragai, Marco; Geraldes, Carlos F G C; Hermann, Petr; Luchinat, Claudio; Parigi, Giacomo; Teixeira, João M C

    2012-03-01

    Pseudocontact shifts (pcs) and paramagnetic residual dipolar couplings (rdc) provide structural information that can be used to assess the adequacy of a crystallographic structure to represent the solution structure of a protein. This can be done by attaching a lanthanide binding tag to the protein. There are cases in which only local rearrangements are sufficient to match the NMR data and cases where significant secondary structure or domain rearrangements from the solid state to the solution state are needed. We show that the two cases are easily distinguishable. Whereas the use of solution restraints in the latter case is described in the literature, here we deal with how to obtain a better model of the solution structure in a case (the catalytic domain of the matrix metalloproteinase MMP-1) of the former class. PMID:21945315

  10. In vitro selection of a new lanthanide-dependent DNAzyme for ratiometric sensing lanthanides.

    PubMed

    Huang, Po-Jung Jimmy; Vazin, Mahsa; Liu, Juewen

    2014-10-01

    Developing biosensors for lanthanides is an important but challenging analytical task. To address this problem, in vitro selection of RNA-cleaving DNAzymes was carried out using a library containing a region of 35 random nucleotides in the presence of Lu(3+), since Lu(3+) was reported to be the most efficient lanthanide for RNA cleavage. The resulting DNA sequences can be aligned to a single family with two conserved stretches of nucleotides. One of the representative DNAzymes (named Lu12) was further studied. Lu12 is more active with smaller lanthanides and has the lowest activity in the presence of the largest lanthanide (lutetium). Its cleavage rate is 0.12 min(-1) in the presence of 10 ?M Nd(3+) at pH 6.0. This is a new DNAzyme, and a catalytic beacon sensor is designed by attaching a fluorophore/quencher pair, detecting Nd(3+) down to 0.4 nM (72 parts-per-trillion). This DNAzyme is highly selective for lanthanides as well, showing cleavage only with two nonlanthanide ions: Y(3+) and Pb(2+). We previously reported a DNAzyme named Ce13d, which has similar responses to all the trivalent lanthanides. Combining these two allows for a ratiometric assay that identifies a few large lanthanides. PMID:25199650

  11. Pyridine-based lanthanide complexes combining MRI and NIR luminescence activities.

    PubMed

    Bonnet, Célia S; Buron, Frédéric; Caillé, Fabien; Shade, Chad M; Drahoš, Bohuslav; Pellegatti, Laurent; Zhang, Jian; Villette, Sandrine; Helm, Lothar; Pichon, Chantal; Suzenet, Franck; Petoud, Stéphane; Tóth, Éva

    2012-01-27

    A series of novel triazole derivative pyridine-based polyamino-polycarboxylate ligands has been synthesized for lanthanide complexation. This versatile platform of chelating agents combines advantageous properties for both magnetic resonance (MR) and optical imaging applications of the corresponding Gd(3+) and near-infrared luminescent lanthanide complexes. The thermodynamic stability constants of the Ln(3+) complexes, as assessed by pH potentiometric measurements, are in the range log K(LnL)=17-19, with a high selectivity for lanthanides over Ca(2+), Cu(2+), and Zn(2+). The complexes are bishydrated, an important advantage to obtain high relaxivities for the Gd(3+) chelates. The water exchange of the Gd(3+) complexes (k(ex)(298)=7.7-9.3×10(6) s(-1)) is faster than that of clinically used magnetic resonance imaging (MRI) contrast agents and proceeds through a dissociatively activated mechanism, as evidenced by the positive activation volumes (?V(?)=7.2-8.8 cm(3) mol(-1)). The new triazole ligands allow a considerable shift towards lower excitation energies of the luminescent lanthanide complexes as compared to the parent pyridinic complex, which is a significant advantage in the perspective of biological applications. In addition, they provide increased epsilon values resulting in a larger number of emitted photons and better detection sensitivity. The most conjugated system PheTPy, bearing a phenyl-triazole pendant on the pyridine ring, is particularly promising as it displays the lowest excitation and triplet-state energies associated with good quantum yields for both Nd(3+) and Yb(3+) complexes. Cellular and in vivo toxicity studies in mice evidenced the non-toxicity and the safe use of such bishydrated complexes in animal experiments. Overall, these pyridinic ligands constitute a highly versatile platform for the simultaneous optimization of both MRI and optical properties of the Gd(3+) and the luminescent lanthanide complexes, respectively. PMID:22213187

  12. Protein measurement with the Folin phenol reagent

    Microsoft Academic Search

    O. H. Lowry; N. J. Rosebrough; A. Lewis Farr; R. J. Randall

    1951-01-01

    Since 1922 when Wu proposed the use of the Folin phenol reagent for the measurement of proteins (l), a number of modified analytical pro- cedures ut.ilizing this reagent have been reported for the determination of proteins in serum (2-G), in antigen-antibody precipitates (7-9), and in insulin (10). Although the reagent would seem to be recommended by its great sen- sitivity

  13. Curvature of the Lanthanide Contraction: An Explanation

    SciTech Connect

    Raymond, Kenneth; Wellman, Daniel; Sgarlata, Carmelo; Hill, Aru

    2009-12-21

    A number of studies have shown that for isostructural series of the lanthanides (elements La through Lu), a plot of equivalent metal-ligand bond lengths versus atomic number differs significantly from linearity and can be better fit as a quadratic equation. However, for hydrogen type wave functions, it is the inverse of the average distance of the electron from the nucleus (an estimate of size) that varies linearly with effective nuclear charge. This generates an apparent quadratic dependence of radius with atomic number. Plotting the inverse of lanthanide ion radii (the observed distance minus the ligand size) as a function of effective nuclear charge gives very good linear fits for a variety of lanthanide complexes and materials. Parameters obtained from this fit are in excellent agreement with the calculated Slater shielding constant, k.

  14. Separations of actinides, lanthanides and other metals

    DOEpatents

    Smith, Barbara F. (Los Alamos, NM); Jarvinen, Gordon D. (Los Alamos, NM); Ensor, Dale D. (Cookeville, TN)

    1995-01-01

    An organic extracting solution comprised of a bis(acylpyrazolone or a substituted bis(acylpyrazolone) and an extraction method useful for separating certain elements of the actinide series of the periodic table having a valence of four from one other, and also from one or more of the substances in a group consisting of hexavalent actinides, trivalent actinides, trivalent lanthanides, trivalent iron, trivalent aluminum, divalent metals, and monovalent metals and also from one or more of the substances in a group consisting of hexavalent actinides, trivalent actinides, trivalent lanthanides, trivalent iron, trivalent aluminum, divalent metals, and monovalent metals and also useful for separating hexavalent actinides from one or more of the substances in a group consisting of trivalent actinides, trivalent lanthanides, trivalent iron, trivalent aluminum, divalent metals, and monovalent metals.

  15. Switchable sensitizers stepwise lighting up lanthanide emissions

    PubMed Central

    Zhang, Yan; Jiao, Peng-Chong; Xu, Hai-Bing; Tang, Ming-Jing; Yang, Xiao-Ping; Huang, Shaoming; Deng, Jian-Guo

    2015-01-01

    Analagous to a long-ranged rocket equipped with multi-stage engines, a luminescent compound with consistent emission signals across a large range of concentrations from two stages of sensitizers can be designed. In this approach, ACQ, aggregation-caused quenching effect of sensitizers, would stimulate lanthanide emission below 10?4?M, and then at concentrations higher than 10?3?M, the “aggregation-induced emission” (AIE) effect of luminophores would be activated with the next set of sensitizers for lanthanide emission. Simultaneously, the concentration of the molecules could be monitored digitally by the maximal excitation wavelengths, due to the good linear relationship between the maximal excitation wavelengths and the concentrations {lg(M)}. This model, wherein molecules are assembled with two stages (both AIE and ACQ effect) of sensitizers, may provide a practicable strategy for design and construction of smart lanthanide bioprobes, which are suitable in complicated bioassay systems in which concentration is variable. PMID:25791467

  16. Switchable sensitizers stepwise lighting up lanthanide emissions.

    PubMed

    Zhang, Yan; Jiao, Peng-Chong; Xu, Hai-Bing; Tang, Ming-Jing; Yang, Xiao-Ping; Huang, Shaoming; Deng, Jian-Guo

    2015-01-01

    Analagous to a long-ranged rocket equipped with multi-stage engines, a luminescent compound with consistent emission signals across a large range of concentrations from two stages of sensitizers can be designed. In this approach, ACQ, aggregation-caused quenching effect of sensitizers, would stimulate lanthanide emission below 10(-4)?M, and then at concentrations higher than 10(-3)?M, the "aggregation-induced emission" (AIE) effect of luminophores would be activated with the next set of sensitizers for lanthanide emission. Simultaneously, the concentration of the molecules could be monitored digitally by the maximal excitation wavelengths, due to the good linear relationship between the maximal excitation wavelengths and the concentrations {lg(M)}. This model, wherein molecules are assembled with two stages (both AIE and ACQ effect) of sensitizers, may provide a practicable strategy for design and construction of smart lanthanide bioprobes, which are suitable in complicated bioassay systems in which concentration is variable. PMID:25791467

  17. New bond-valence parameters for lanthanides.

    PubMed

    Trzesowska, Agata; Kruszynski, Rafal; Bartczak, Tadeusz J

    2004-04-01

    The bond-valence method, especially the valence-sum rule, is very useful for checking if the structures formed by trivalent lanthanides are correct. In this work bond-valence parameters (Rij), which connect bond valences and bond lengths, have been computed for a large number of bonds taken from the Cambridge Structural Database, Version 5.24 (2002) [Allen (2002). Acta Cryst. B58, 380-388]. The calculated values of bond-valence parameters for metal-organic compounds decrease with an increase in lanthanide atomic number; the Rij values are also smaller than bond-valence parameters calculated for inorganic compounds. A summary of bond-valence sums calculated for Rij given in this work and reported in the literature, and a functional correlation between lanthanide-oxygen distances and coordination number are presented. PMID:15017089

  18. Physical characteristics of lanthanide complexes that act as magnetization transfer (MT) contrast agents

    NASA Astrophysics Data System (ADS)

    Zhang, Shanrong; Sherry, A. Dean

    2003-02-01

    Rapid water exchange is normally considered a prerequisite for efficient Gd 3+-based MRI contrast agents. Yet recent measures of exchange rates in some Gd 3+ complexes have shown that water exchange can become limiting when such complexes are attached to larger macromolecular structures. A new class of lanthanide complexes that display unusually slow water exchange (bound water lifetimes ( ?M298) > 10 ?s) has recently been reported. This apparent disadvantage may be taken advantage of by switching the metal ion from gadolinium(III) to a lanthanide that shifts the bound water resonance substantially away from bulk water. Given appropriate water exchange kinetics, one can then alter the intensity of the bulk water signal by selective presaturation of this highly shifted, Ln3+-bound water resonance. This provides the basis of a new method to alter MR image contrast in tissue. We have synthesized a variety of DOTA-tetra(amide) ligands to evaluate as potential magnetization transfer (MT) contrast agents and found that the bound water lifetimes in these complexes are sensitive to both ligand structure (a series of Eu 3+ complexes have ?M298 values that range from 1 to 1300 ?s) and the identity of the paramagnetic Ln3+ cation (from 3 to 800 ?s for a single ligand). This demonstrates that it may be possible either to fine-tune the ligand structure or to select proper lanthanide cation to create an optimal MT agent for any clinical imaging field.

  19. Sensing Lanthanide Metal Content in Biological Tissues with Magnetic Resonance Spectroscopy

    PubMed Central

    Hingorani, Dina V.; Gonzalez, Sandra I.; Li, Jessica F.; Pagel, Mark D.

    2013-01-01

    The development and validation of MRI contrast agents consisting of a lanthanide chelate often requires a determination of the concentration of the agent in ex vivo tissue. We have developed a protocol that uses 70% nitric acid to completely digest tissue samples that contain Gd(III), Dy(III), Tm(III), Eu(III), or Yb(III) ions, or the MRI contrast agent gadodiamide. NMR spectroscopy of coaxial tubes containing a digested sample and a separate control solution of nitric acid was used to rapidly and easily measure the bulk magnetic susceptibility (BMS) shift caused by each lanthanide ion and gadodiamide. Each BMS shift was shown to be linearly correlated with the concentration of each lanthanide ion and gadodiamide in the 70% nitric acid solution and in digested rat kidney and liver tissues. These concentration measurements had outstanding precision, and also had good accuracy for concentrations ?10 mM for Tm(III) Eu(III), and Yb(III), and ?3 mM for Gd(III), gadodiamide, and Dy(III). Improved sample handling methods are needed to improve measurement accuracy for samples with lower concentrations. PMID:24152931

  20. Structural biology of the lanthanides-mining rare earths in the Protein Data Bank.

    PubMed

    Djinovic-Carugo, Kristina; Carugo, Oliviero

    2015-02-01

    With its about 100,000 three-dimensional structures, the Protein Data Bank is a copious source of information: it contains also some hundreds of structures of macromolecules complexed with lanthanide cations, which are examined here. These cations, which are found in a wide variety of protein types, were introduced to determine the structures, by exploiting their anomalous dispersion (in crystallographic studies, where they are also used as crystallization additives) or the paramagnetic pseudocontact shifts (in NMR analyses). The coordination numbers in the first coordination sphere are very variable, though they tend to be close to those that are observed in small molecules or in water solution. The coordination polyhedra are also quite variable as it can be expected for large cations. Interestingly, lanthanide cations are frequently observed in packing bridges between symmetry equivalent molecules in crystals, where they tend to form polynuclear complexes, with up to seven cations bridged by water/hydroxide ligands. PMID:25528480

  1. U. S. Veterinary Immune Reagents Network: Progress with poultry immune reagents development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A major obstacle to advances in veterinary immunology and disease research is the lack of sufficient immunological reagents specific for veterinary animal species. In 2006, U. S. Veterinary Immune Reagent Network (VIRN) Consortium (www.vetimm.org) was developed to develop immune reagents against ma...

  2. Inventory management and reagent supply for automated chemistry.

    PubMed

    Kuzniar, E

    1999-08-01

    Developments in automated chemistry have kept pace with developments in HTS such that hundreds of thousands of new compounds can be rapidly synthesized in the belief that the greater the number and diversity of compounds that can be screened, the more successful HTS will be. The increasing use of automation for Multiple Parallel Synthesis (MPS) and the move to automated combinatorial library production is placing an overwhelming burden on the management of reagents. Although automation has improved the efficiency of the processes involved in compound synthesis, the bottleneck has shifted to ordering, collating and preparing reagents for automated chemistry resulting in loss of time, materials and momentum. Major efficiencies have already been made in the area of compound management for high throughput screening. Most of these efficiencies have been achieved with sophisticated library management systems using advanced engineering and data handling for the storage, tracking and retrieval of millions of compounds. The Automation Partnership has already provided many of the top pharmaceutical companies with modular automated storage, preparation and retrieval systems to manage compound libraries for high throughput screening. This article describes how these systems may be implemented to solve the specific problems of inventory management and reagent supply for automated chemistry. PMID:10469883

  3. LANTHANIDE-BASED IMAGING OF PROTEIN-PROTEIN INTERACTIONS IN LIVE CELLS

    PubMed Central

    Rajendran, Megha; Yapici, Engin; Miller, Lawrence W.

    2013-01-01

    In order to deduce the molecular mechanisms of biological function, it is necessary to monitor changes in the sub-cellular location, activation and interaction of proteins within living cells in real time. Förster resonance energy transfer (FRET)-based biosensors that incorporate genetically encoded, fluorescent proteins permit high spatial resolution imaging of protein–protein interactions or protein conformational dynamics. However, non-specific fluorescence background often obscures small FRET signal changes, and intensity-based biosensor measurements require careful interpretation and several control experiments. These problems can be overcome by using lanthanide (Tb(III) or Eu(III)) complexes as donors and green fluorescent protein (GFP) or other conventional fluorophores as acceptors. Essential features of this approach are the long-lifetime (~ms) luminescence of Tb(III) complexes and time-gated luminescence microscopy. This allows pulsed excitation followed by a brief delay that eliminates nonspecific fluorescence before detection of Tb(III)-to-GFP emission. The challenges of intracellular delivery, selective protein labeling, and time-gated imaging of lanthanide luminescence are presented, and recent efforts to investigate the cellular uptake of lanthanide probes are reviewed. Data is presented showing that conjugation to arginine-rich, cell penetrating peptides (CPPs) can be used as a general strategy for cellular delivery of membrane impermeable lanthanide complexes. A heterodimer of a luminescent Tb(III) complex, Lumi4, linked to trimethoprim (TMP) and conjugated to nonaarginine via a reducible disulfide linker rapidly (~10 min) translocates into the cytoplasm of Maden Darby canine kidney cells from culture medium. With this reagent, the intracellular interaction between GFP fused to FK506 binding protein 12 (GFP-FKBP12) and the rapamycin binding domain of mTOR fused to Escherichia coli dihydrofolate reductase (FRB-eDHFR) was imaged at high signal-to-noise ratio with fast (1–3 s) image acquisition using a time-gated luminescence microscope. The data reviewed and presented here show that lanthanide biosensors enable fast, sensitive and technically simple imaging of protein-protein interactions in live cells. PMID:24144069

  4. TREATMENT OF MTBE USING FENTON'S REAGENT

    EPA Science Inventory

    This paper addresses the removal of MTBE from water, using Fenton's Reagent. Although complete mineralization of MTBE by Fenton's Reagent was not achieved, greater than 99% destruction of MTBE was realized. This was accomplished at a Fe+2:H2O2 ratio of 1:1 and one hour of contact...

  5. Lanthanide(III) Complexation with an Amide Derived Pyridinophane.

    PubMed

    Castro, Goretti; Bastida, Rufina; Macías, Alejandro; Pérez-Lourido, Paulo; Platas-Iglesias, Carlos; Valencia, Laura

    2015-02-16

    Herein we report a detailed investigation of the solid state and solution structures of lanthanide(III) complexes with the 18-membered pyridinophane ligand containing acetamide pendant arms TPPTAM (TPPTAM = 2,2',2?-(3,7,11-triaza-1,5,9(2,6)-tripyridinacyclododecaphane-3,7,11-triyl)triacetamide). The ligand crystallizes in the form of a clathrated hydrate, where the clathrated water molecule establishes hydrogen-bonding interactions with the amide NH groups and two N atoms of the macrocycle. The X-ray structures of 13 different Ln(3+) complexes obtained as the nitrate salts (Ln(3+) = La(3+)-Yb(3+), except Pm(3+)) have been determined. Additionally, the X-ray structure of the La(3+) complex obtained as the triflate salt was also obtained. In all cases the ligand provides 9-fold coordination to the Ln(3+) ion, ten coordination being completed by an oxygen atom of a coordinated water molecule or a nitrate or triflate anion. The bond distances of the metal coordination environment show a quadratic change along the lanthanide series, as expected for isostructural series of Ln(3+) complexes. Luminescence lifetime measurements obtained from solutions of the Eu(3+) and Tb(3+) complexes in H2O and D2O point to the presence of a water molecule coordinated to the metal ion in aqueous solutions. The analysis of the Ln(3+)-induced paramagnetic shifts indicates that the complexes are ten-coordinated throughout the lanthanide series from Ce(3+) to Yb(3+), and that the solution structure is very similar to the structures observed in the solid state. The complexes of the light Ln(3+) ions are fluxional due to a fast ?(??????) ? ?(??????) interconversion that involves the inversion of the macrocyclic ligand and the rotation of the acetamide pendant arms. The complexes of the small Ln(3+) ions are considerably more rigid, the activation free energy determined from VT (1)H NMR for the Lu(3+) complex being ?G(?)298 = 72.4 ± 5.1 kJ mol(-1). PMID:25615908

  6. 21 CFR 866.3480 - Respiratory syncytial virus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 false Respiratory syncytial virus serological reagents. 866.3480... § 866.3480 Respiratory syncytial virus serological reagents. (a) Identification. Respiratory syncytial virus serological reagents are devices...

  7. 21 CFR 866.3480 - Respiratory syncytial virus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Respiratory syncytial virus serological reagents. 866.3480... § 866.3480 Respiratory syncytial virus serological reagents. (a) Identification. Respiratory syncytial virus serological reagents are devices...

  8. 21 CFR 866.3520 - Rubeola (measles) virus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Rubeola (measles) virus serological reagents. 866.3520... § 866.3520 Rubeola (measles) virus serological reagents. (a) Identification. Rubeola (measles) virus serological reagents are devices...

  9. 21 CFR 866.3480 - Respiratory syncytial virus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Respiratory syncytial virus serological reagents. 866.3480... § 866.3480 Respiratory syncytial virus serological reagents. (a) Identification. Respiratory syncytial virus serological reagents are devices...

  10. 21 CFR 866.3520 - Rubeola (measles) virus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Rubeola (measles) virus serological reagents. 866.3520... § 866.3520 Rubeola (measles) virus serological reagents. (a) Identification. Rubeola (measles) virus serological reagents are devices...

  11. 21 CFR 866.3520 - Rubeola (measles) virus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Rubeola (measles) virus serological reagents. 866.3520... § 866.3520 Rubeola (measles) virus serological reagents. (a) Identification. Rubeola (measles) virus serological reagents are devices...

  12. 21 CFR 866.3480 - Respiratory syncytial virus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Respiratory syncytial virus serological reagents. 866.3480... § 866.3480 Respiratory syncytial virus serological reagents. (a) Identification. Respiratory syncytial virus serological reagents are devices...

  13. 21 CFR 866.3520 - Rubeola (measles) virus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Rubeola (measles) virus serological reagents. 866.3520... § 866.3520 Rubeola (measles) virus serological reagents. (a) Identification. Rubeola (measles) virus serological reagents are devices...

  14. 21 CFR 866.3480 - Respiratory syncytial virus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Respiratory syncytial virus serological reagents. 866.3480... § 866.3480 Respiratory syncytial virus serological reagents. (a) Identification. Respiratory syncytial virus serological reagents are devices...

  15. 21 CFR 864.8100 - Bothrops atrox reagent.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Reagents § 864.8100 Bothrops atrox reagent. (a) Identification. A Bothrops atrox reagent is a device made from snake venom and used to determine blood fibrinogen levels to aid in the evaluation of disseminated intravascular...

  16. 21 CFR 864.8100 - Bothrops atrox reagent.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Reagents § 864.8100 Bothrops atrox reagent. (a) Identification. A Bothrops atrox reagent is a device made from snake venom and used to determine blood fibrinogen levels to aid in the evaluation of disseminated intravascular...

  17. 21 CFR 864.8100 - Bothrops atrox reagent.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Reagents § 864.8100 Bothrops atrox reagent. (a) Identification. A Bothrops atrox reagent is a device made from snake venom and used to determine blood fibrinogen levels to aid in the evaluation of disseminated intravascular...

  18. 21 CFR 864.8100 - Bothrops atrox reagent.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...Reagents § 864.8100 Bothrops atrox reagent. (a) Identification. A Bothrops atrox reagent is a device made from snake venom and used to determine blood fibrinogen levels to aid in the evaluation of disseminated intravascular...

  19. 21 CFR 864.8100 - Bothrops atrox reagent.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...Reagents § 864.8100 Bothrops atrox reagent. (a) Identification. A Bothrops atrox reagent is a device made from snake venom and used to determine blood fibrinogen levels to aid in the evaluation of disseminated intravascular...

  20. Inactivation of rabies diagnostic reagents by gamma radiation

    SciTech Connect

    Gamble, W.C.; Chappell, W.A.; George, E.H.

    1980-11-01

    Treatment of CVS-11 rabies adsorbing suspensions and street rabies infected mouse brains with gamma radiation resulted in inactivated reagents that are safer to distribute and use. These irradiated reagents were as sensitive and reactive as the nonirradiated control reagents.

  1. 21 CFR 660.20 - Blood Grouping Reagent.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 7 2014-04-01 2014-04-01 false Blood Grouping Reagent. 660.20 Section 660...FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.20 Blood Grouping Reagent. (a) Proper name and...

  2. 21 CFR 660.20 - Blood Grouping Reagent.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 7 2012-04-01 2012-04-01 false Blood Grouping Reagent. 660.20 Section 660...FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.20 Blood Grouping Reagent. (a) Proper name and...

  3. 21 CFR 660.20 - Blood Grouping Reagent.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 7 2013-04-01 2013-04-01 false Blood Grouping Reagent. 660.20 Section 660...FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.20 Blood Grouping Reagent. (a) Proper name and...

  4. 21 CFR 660.20 - Blood Grouping Reagent.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 7 2011-04-01 2010-04-01 true Blood Grouping Reagent. 660.20 Section 660...FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.20 Blood Grouping Reagent. (a) Proper name and...

  5. 21 CFR 660.20 - Blood Grouping Reagent.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 7 2010-04-01 2010-04-01 false Blood Grouping Reagent. 660.20 Section 660...FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.20 Blood Grouping Reagent. (a) Proper name and...

  6. Tendency of the Nephelauxetic Effect to Vary in a Series of Lanthanide Complexes with Allyl Acetoacetate

    NASA Astrophysics Data System (ADS)

    Mishchenko, A. M.; Trunova, E. K.; Berezhnytskaya, A. S.; Rogovtsov, A. A.

    2015-01-01

    The complexation of allyl acetoacetate with Pr3+, Nd3+, Ho3+, Er3+, and Tm3+ in aqueous solution was studied by electronic absorption spectroscopy. It was shown that allyl acetoacetate at pH 5.50 formed 1:1 and 1:2 complexes with the lanthanide ions depending on the reagent ratio. Intensity parameters ?? in addition to bond parameters using the free ions as comparative standards were calculated for the 1:2 complexes. It was established that the nephelauxetic ratio ? increased smoothly and approached unity in the order Pr3+ < Nd3+ < Ho3+ < Er3+ < Tm3+. Such variation was explained in the framework of covalent and polarization models.

  7. Manufacturability of lab on chip devices : reagent-filled reservoirs bonding process and its effect on reagents flow pattern

    E-print Network

    Saber, Aabed (Aabed Saud)

    2013-01-01

    In its lab-on-a-chip product, Daktari Diagnostics utilizes "reagent-filled reservoirs" as a means of storing and delivering the liquid reagent. During the clinical trials of the product, undesired reagent flow patterns ...

  8. 21 CFR 866.3370 - Mycobacterium tuberculosis immunofluorescent reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Mycobacterium tuberculosis immunofluorescent reagents... § 866.3370 Mycobacterium tuberculosis immunofluorescent reagents...Identification. Mycobacterium tuberculosis immunofluorescent...

  9. 21 CFR 866.3370 - Mycobacterium tuberculosis immunofluorescent reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Mycobacterium tuberculosis immunofluorescent reagents... § 866.3370 Mycobacterium tuberculosis immunofluorescent reagents...Identification. Mycobacterium tuberculosis immunofluorescent...

  10. 21 CFR 866.3370 - Mycobacterium tuberculosis immunofluorescent reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Mycobacterium tuberculosis immunofluorescent reagents... § 866.3370 Mycobacterium tuberculosis immunofluorescent reagents...Identification. Mycobacterium tuberculosis immunofluorescent...

  11. 21 CFR 866.3370 - Mycobacterium tuberculosis immunofluorescent reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Mycobacterium tuberculosis immunofluorescent reagents... § 866.3370 Mycobacterium tuberculosis immunofluorescent reagents...Identification. Mycobacterium tuberculosis immunofluorescent...

  12. 21 CFR 866.3470 - Reovirus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3470 Reovirus serological reagents. (a) Identification....

  13. 21 CFR 866.3175 - Cytomegalovirus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3175 Cytomegalovirus serological reagents. (a)...

  14. 21 CFR 866.3165 - Cryptococcus neoformans serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3165 Cryptococcus neoformans serological reagents. (a)...

  15. 21 CFR 866.3405 - Poliovirus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3405 Poliovirus serological reagents. (a) Identification....

  16. 21 CFR 866.3125 - Citrobacter spp. serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3125 Citrobacter spp. serological reagents. (a) Identification....

  17. 21 CFR 866.3020 - Adenovirus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3020 Adenovirus serological reagents. (a) Identification....

  18. 21 CFR 866.3600 - Schistosoma spp. serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3600 Schistosoma spp. serological reagents. (a) Identification....

  19. 21 CFR 866.3165 - Cryptococcus neoformans serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3165 Cryptococcus neoformans serological reagents. (a)...

  20. 21 CFR 866.3020 - Adenovirus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3020 Adenovirus serological reagents. (a) Identification....

  1. 21 CFR 866.3250 - Erysipelothrix rhusiopathiae serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3250 Erysipelothrix rhusiopathiae serological reagents. (a)...

  2. 21 CFR 866.3660 - Shigella spp. serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3660 Shigella spp. serological reagents. (a) Identification....

  3. 21 CFR 866.3250 - Erysipelothrix rhusiopathiae serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3250 Erysipelothrix rhusiopathiae serological reagents. (a)...

  4. 21 CFR 866.3300 - Haemophilus spp. serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3300 Haemophilus spp. serological reagents. (a) Identification....

  5. 21 CFR 866.3490 - Rhinovirus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3490 Rhinovirus serological reagents. (a) Identification....

  6. 21 CFR 866.3930 - Vibrio cholerae serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3930 Vibrio cholerae serological reagents. (a) Identification....

  7. 21 CFR 866.3175 - Cytomegalovirus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3175 Cytomegalovirus serological reagents. (a)...

  8. 21 CFR 866.3600 - Schistosoma spp. serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3600 Schistosoma spp. serological reagents. (a) Identification....

  9. 21 CFR 866.3395 - Norovirus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3395 Norovirus serological reagents. (a) Identification....

  10. 21 CFR 866.3120 - Chlamydia serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3120 Chlamydia serological reagents. (a) Identification....

  11. 21 CFR 866.3020 - Adenovirus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3020 Adenovirus serological reagents. (a) Identification....

  12. 21 CFR 866.3470 - Reovirus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3470 Reovirus serological reagents. (a) Identification....

  13. 21 CFR 866.3470 - Reovirus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3470 Reovirus serological reagents. (a) Identification....

  14. 21 CFR 866.3600 - Schistosoma spp. serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3600 Schistosoma spp. serological reagents. (a) Identification....

  15. 21 CFR 866.3460 - Rabiesvirus immuno-fluorescent reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3460 Rabiesvirus immuno-fluorescent reagents. (a)...

  16. 21 CFR 866.3460 - Rabiesvirus immuno-fluorescent reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3460 Rabiesvirus immuno-fluorescent reagents. (a)...

  17. 21 CFR 866.3255 - Escherichia coli serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3255 Escherichia coli serological reagents. (a) Identification....

  18. 21 CFR 866.3200 - Echinococcus spp. serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3200 Echinococcus spp. serological reagents. (a) Identification....

  19. 21 CFR 866.3405 - Poliovirus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3405 Poliovirus serological reagents. (a) Identification....

  20. 21 CFR 866.3125 - Citrobacter spp. serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3125 Citrobacter spp. serological reagents. (a) Identification....

  1. 21 CFR 866.3140 - Corynebacterium spp. serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3140 Corynebacterium spp. serological reagents. (a) Identification....

  2. 21 CFR 866.3660 - Shigella spp. serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3660 Shigella spp. serological reagents. (a) Identification....

  3. 21 CFR 866.3280 - Francisella tularensis serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3280 Francisella tularensis serological reagents. (a)...

  4. 21 CFR 866.3200 - Echinococcus spp. serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3200 Echinococcus spp. serological reagents. (a) Identification....

  5. 21 CFR 866.3175 - Cytomegalovirus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3175 Cytomegalovirus serological reagents. (a)...

  6. 21 CFR 866.3120 - Chlamydia serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3120 Chlamydia serological reagents. (a) Identification....

  7. 21 CFR 866.3375 - Mycoplasma spp. serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3375 Mycoplasma spp. serological reagents. (a) Identification....

  8. 21 CFR 866.3020 - Adenovirus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3020 Adenovirus serological reagents. (a) Identification....

  9. 21 CFR 866.3340 - Klebsiella spp. serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3340 Klebsiella spp. serological reagents. (a) Identification....

  10. 21 CFR 866.3200 - Echinococcus spp. serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3200 Echinococcus spp. serological reagents. (a) Identification....

  11. Evaluation of triazole-chelated lanthanides as chemically stabile bioimaging agents.

    PubMed

    Indapurkar, Amruta; Henriksen, Brian; Tolman, Justin; Fletcher, James

    2013-08-01

    Europium (Eu), dysprosium (Dy), samarium (Sm), and terbium (Tb) complexes were prepared using the neutral tridentate chelator 2,6-bis(1-benzyl-1,2,3-triazol-4-yl)pyridine and one equivalent of each lanthanide salt. The physicochemical, aerodynamic, and in vitro cellular properties of each lanthanide metal complex were studied to determine their viability as cell surface fluorescent probes. Each compound was characterized by electrospray ionization mass spectroscopy (ESI-MS), ultraperformance liquid chromatography (UPLC), differential scanning calorimetry (DSC), and thermogravimetic analysis (TGA). Upon excitation at 320 nm each complex displayed characteristic lanthanide-based fluorescence emission in the visible wavelength range with stokes shifts greater than 200 nm. Each complex was found to be chemically stable when exposed to pH range of 1-11 for 72 h and resistant to photobleaching. To simulate pulmonary administration of these fluorophores, the aerodynamic properties of the Eu and Tb complexes were determined using a next generation impactor (NGI). This measurement confirmed that the complexes retain their fluorescence emission properties after nebulization. Cellular cytotoxicity was determined on A-549 lung cancer cell line using methylthiazol tetrazolium (MTT) cytotoxicity assay at 24, 48, and 72 h postexposure to the complexes. The complexes showed a dose and time-dependent effect on the percent viability of the cells. PMID:23761019

  12. Investigation of lanthanides as neutron multipliers for hybrid and fusion reactor blankets

    SciTech Connect

    Sahin, Sumer

    1982-04-01

    The neutronic performance of three lanthanides (/sup 149/Sm, europium, and gadolinium) as neutron multiplier for the blanket of a fusion-fission (hybrid) and a pure fusion reactor has been evaluated and compared with that of beryllium and lead. During the calculations, the fission zone is made up of UO/sub 2/ rods from the LOTUS experimental hybrid facility now under construction at the Nuclear Engineering Laboratory of the Swiss Federal Institute of Technology in Lausanne. In fusion blanket the fuel zone is replaced by pure lithium. The calculations were performed for two different boundary conditions for the left boundary: (a) reflecting, representative of a typical confinement geometry, and (b) vacuum, which represents a typical blanket experiment in plane geometry. For a vacuum left boundary, threshold reactions are reduced by a factor of about 2 while 1/v-type reactions are decreased by a factor of between 5 and 10, as a consequence of the softer spectrum produced by a reflecting left boundary. In general, the results, notably tritium breeding and energy multiplication, are comparable for the lanthanide multipliers and for beryllium and lead if the left boundary is a vacuum. The use of /sup 149/Sm is slightly less effective than europium or gadolinium and all of the lanthanides perform better for a vacuum left boundary than for the reflecting case. The analyses presented here also illustrate the importance of potential spectral shifts that can occur as the result of experimental exigencies.

  13. Partial Molar Volumes for Lanthanide Sesquioxides in Sodium Silicate Melts

    NASA Astrophysics Data System (ADS)

    Courtial, P.; Dingwell, D. B.

    2004-12-01

    Lanthanides are of great interest in igneous petrology as trace indicators of magmatic processes that control the origin and evolution of igneous rocks. A key to the petrogenetic modelling of magmatic processes and to determine the phase diagrams of lanthanide host phases is the accurate determination of the physico-chemical and thermodynamic properties of lanthanide-containing materials, such as the volumetric properties of lanthanide-bearing silicate melts. Therefore, we have undertaken to provide a new reliable volumetric data set for lanthanide-bearing silicate melts which allows the available models in the literature to be extended to lanthanide-bearing melts. For this purpose, the densities of various lanthanide-bearing silicate melts distributed along various pseudo-binary joins, where the end-members are Na-disilicate and one of the lanthanide sesquioxides (i.e., Ce2O3, Pr2O3, Nd2O3, Sm2O3, Eu2O3, Gd2O3, Tb2O3, Dy2O3, Ho2O3, Er2O3, Tm2O3 and Yb2O3), have been measured using the double-bob Archimedean method. The present results show that the addition of any lanthanide to Na-disilicate leads to an increase in the melt density and that the melt density increases with increasing atomic number of the lanthanide. From the present density data set, the molar volumes of these melts have been calculated and the partial molar volumes of each lanthanide sesquioxide in these melts have been determined using a linear regression through each pseudo-binary join (i.e., Na-disilicate - lanthanide sesquioxide). This study indicates ideal behaviour with respect to the molar volume (i.e., a linear variation of the molar volume along each pseudo-binary join) for Na-silicate melts containing up to 10 mol% of lanthanide oxide. Comparison between the partial molar volumes of lanthanide sesquioxides obtained in this study and the molar volumes of molten lanthanide sesquioxides given in the literature raise the possibility however that this ideality is not maintained along the entire Na-disilicate - lanthanide sesquioxide pseudo-binary joins. Excess volumes of mixing appear to be required to describe the combined volumetric data set.

  14. New lanthanide-nitrogen bond-valence parameters.

    PubMed

    Trzesowska, Agata; Kruszynski, Rafal; Bartczak, Tadeusz J

    2005-08-01

    The bond-valence parameters (R(ij)), which connect bond valences and bond lengths, have been computed for lanthanide-nitrogen bonds. It has been found that values of bond-valence parameters decrease with increasing lanthanide atomic number in coordination compounds, and that they are smaller than the R(ij) parameters of inorganic compounds. As expected, the lanthanide-nitrogen bond-valence parameters are larger than lanthanide-oxygen bond-valence parameters. There are no obvious dependencies between the number of N atoms in the coordination sphere and the bond-valence parameter value. PMID:16041092

  15. Advances in tandem reactions with organozinc reagents.

    PubMed

    Kim, Ju Hyun; Ko, Young Ok; Bouffard, Jean; Lee, Sang-Gi

    2015-04-10

    The design and implementation of tandem reactions provides organic chemists with numerous challenges, in particular that of undesired cross-reactivity between substrates. Among organometallics, the use of organozinc reagents in tandem reactions provides several advantages as a result of their broad functional group tolerance and compatibility with transition metals. This review highlights prominent examples of recent advances in tandem reactions with organozinc reagents that illustrate their potential in organic synthesis. PMID:25708795

  16. The Actinide-Lanthanide Separation Process

    SciTech Connect

    Lumetta, Gregg J.; Gelis, Artem V.; Carter, Jennifer C.; Niver, Cynthia M.; Smoot, Margaret R.

    2014-02-21

    The Actinide-Lanthanide SEParation (ALSEP) process is described. The process uses an extractant phase consisting of either N,N,N',N'-tetraoctyldiglycolamide (TODGA) or N,N,N',N'-tetra(2 ethylhexyl)diglycolamide (T2EHDGA) combined with 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]). The neutral TODGA or T2EHDGA serves to co-extract the trivalent actinide and lanthanide ions from nitric acid media. Switching the aqueous phase chemistry to a citrate buffered diethylenetriaminepentaacetic acid (DTPA) solution at pH 2.5 to 4 results in selective transfer of the actinides to the aqueous phase, thus resulting in separation of these two groups of elements.

  17. Coordination of lanthanides by two polyamino polycarboxylic macrocycles: formation of highly stable lanthanide complexes

    SciTech Connect

    Loncin, M.F.; Desreux, J.F.; Merciny, E.

    1986-07-16

    The formation constants of a few lanthanide complexes with DOTA (1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid) and TETA (1,4,8,11-tetraazacyclotetradecane-N,N',N'',N'''-tetraacetic acid) have been measured by potentiometric and competition methods. The ligand DOTA forms the most stable lanthanide chelates known so far (log K/sub ML/ = 28.2-29.2) while the stability of the TETA compounds at 80 /sup 0/C (log K/sub ML/ = 14.5-16.5) is comparable to the stability of the EDTA complexes. A competition method with the oxalate anion as a probe had to be used for determining the formation constants of the DOTA lanthanide chelates because of the high stability of these compounds. The relative stability of the DOTA and TETA complexes in accounted for by steric factors with reference to known solution- and solid-state structures. 20 references, 2 tables.

  18. Lanthanide single molecule magnets: progress and perspective.

    PubMed

    Zhang, Peng; Zhang, Li; Tang, Jinkui

    2015-03-01

    The last few years have seen a huge renaissance in the study of single molecule magnets (SMMs) thanks to the extensive applications of lanthanide ions with large inherent anisotropy in molecular magnetism. Particularly, the recent theoretical developments and the experimental expansion into the organometallic avenue have led to an eye-catching boost in this field. Here we highlight the recent progress in this fascinating and challenging field, with emphasis on several combined experimental and theoretical studies. PMID:25641200

  19. Actinide and lanthanide separation process (ALSEP)

    DOEpatents

    Guelis, Artem V.

    2013-01-15

    The process of the invention is the separation of minor actinides from lanthanides in a fluid mixture comprising, fission products, lanthanides, minor actinides, rare earth elements, nitric acid and water by addition of an organic chelating aid to the fluid; extracting the fluid with a solvent comprising a first extractant, a second extractant and an organic diluent to form an organic extractant stream and an aqueous raffinate. Scrubbing the organic stream with a dicarboxylic acid and a chelating agent to form a scrubber discharge. The scrubber discharge is stripped with a simple buffering agent and a second chelating agent in the pH range of 2.5 to 6.1 to produce actinide and lanthanide streams and spent organic diluents. The first extractant is selected from bis(2-ethylhexyl)hydrogen phosphate (HDEHP) and mono(2-ethylhexyl)2-ethylhexyl phosphonate (HEH(EHP)) and the second extractant is selected from N,N,N,N-tetra-2-ethylhexyl diglycol amide (TEHDGA) and N,N,N',N'-tetraoctyl-3-oxapentanediamide (TODGA).

  20. Shifting Attention

    ERIC Educational Resources Information Center

    Ingram, Jenni

    2014-01-01

    This article examines the shifts in attention and focus as one teacher introduces and explains an image that represents the processes involved in a numeric problem that his students have been working on. This paper takes a micro-analytic approach to examine how the focus of attention shifts through what the teacher and students do and say in the…

  1. Method of determining lanthanides in a transition element host. [luminescence

    Microsoft Academic Search

    E. L. De Kalb; V. A. Fassel

    1976-01-01

    A phosphor composition contains a lanthanide activator element within a host matrix having a transition element as a major component. The host matrix is composed of certain rare earth phosphates or vanadates such as YPOâ with a portion of the rare earth replaced with one or more of the transition elements. On x-ray or other electromagnetic excitation, trace lanthanide impurities

  2. Improved method for extracting lanthanides and actinides from acid solutions

    DOEpatents

    Horwitz, E.P.; Kalina, D.G.; Kaplan, L.; Mason, G.W.

    1983-07-26

    A process for the recovery of actinide and lanthanide values from aqueous acidic solutions uses a new series of neutral bi-functional extractants, the alkyl(phenyl)-N,N-dialkylcarbamoylmethylphosphine oxides. The process is suitable for the separation of actinide and lanthanide values from fission product values found together in high-level nuclear reprocessing waste solutions.

  3. Phthalamide-lanthanide complexes for use as luminescent markers

    DOEpatents

    Raymond, Kenneth N. (Berkeley, CA); Petoud, Stephane (Pittsburgh, PA); Cohen, Seth (Boston, MA); Xu, Jide (Berkeley, CA)

    2008-10-28

    The present invention provides luminescent lanthanide metal chelates comprising a metal ion of the lanthanide series and a complexing agent comprising at least one phthalamidyl moiety. Also provided are probes incorporating the phthalamidyl ligands of the invention and methods utilizing the ligands of the invention and probes comprising the ligands of the invention.

  4. Phthalamide lanthanide complexes for use as luminescent markers

    DOEpatents

    Raymond, Kenneth N. (Berkeley, CA); Petoud, Stephane (Berkeley, CA); Cohen, Seth M. (Boston, MA); Xu, Jide (Berkeley, CA)

    2003-01-01

    The present invention provides luminescent lanthanide metal chelates comprising a metal ion of the lanthanide series and a complexing agent comprising at least one phthalamidyl moiety. Also provided are probes incorporating the phthalamidyl ligands of the invention and methods utilizing the ligands of the invention and probes comprising the ligands of the invention.

  5. Salicylamide-lanthanide complexes for use as luminescent markers

    DOEpatents

    Raymond, Kenneth N. (Berkeley, CA); Petoud, Stephane (Berkeley, CA); Cohen, Seth (West Lake Village, CA); Xu, Jide (Berkeley, CA)

    2002-01-01

    The present invention provides luminescent lanthanide metal chelates comprising a metal ion of the lanthanide series and a complexing agent comprising at least one salicylamidyl moiety. Also provided are probes incorporating the salicylamidyl ligands of the invention and methods utilizing the ligands of the invention and probes comprising the ligands of the invention.

  6. U.S. VETERINARY IMMUNE REAGENTS NETWORK: PROGRESS WITH POULTRY IMMUNE REAGENTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A major obstacle to advances in veterinary immunology and disease control is the lack of sufficient immunological reagents specific for ruminants, swine, poultry, equine and aquaculture species. Sets of reagents, i.e., monoclonal (mAb) and polyclonal antibodies, that can identify the major leukocyt...

  7. Unnatural Isotopic Composition of Lithium Reagents

    USGS Publications Warehouse

    Qi, H.P.; Coplen, T.B.; Wang, Q. Zh; Wang, Y.-H.

    1997-01-01

    Isotopic analysis of 39 lithium reagents from several manufacturers indicates that seven were artificially depleted in 6Li significantly in excess of the variation found in terrestrial materials. The atomic weight of lithium in analyzed reagents ranged from 6.939 to 6.996, and ??7-Li, reported relative to L-SVEC lithium carbonate, ranged from -11 to +3013???. This investigation indicates that 6Li-depleted reagents are now found on chemists' shelves, and the labels of these 6Li-depleted reagents do not accurately reflect the atomic and (or) molecular weights of these reagents. In 1993, IUPAC issued the following statement: "Commercially available Li materials have atomic weights that range between 6.94 and 6.99; if a more accurate value is required, it must be determined for the specific material." This statement has been found to be incorrect In two of the 39 samples analyzed, the atomic weight of Li was in excess of 6.99.

  8. Electron transfer processes in double lanthanide activated YPO 4

    NASA Astrophysics Data System (ADS)

    Dorenbos, P.; Bos, A. J. J.; Poolton, N. R. J.

    2011-05-01

    This work reviews electron transfer processes in double lanthanide doped YPO 4 studied using a diversity of optical techniques. The aim is to identify those transfer processes and to relate them with the location of lanthanide electron donor and lanthanide electron acceptor states within the bandgap of YPO 4. Electron transfer from the valence band to a trivalent lanthanide impurity or to the conduction band was studied by traditional single photon excitation on single lanthanide doped YPO 4. This work reports on YPO 4 doped with the electron donor Ce 3+ and co-doped with an electron acceptor Pr 3+, Er 3+, Nd 3+, Ho 3+, Dy 3+, Tm 3+, or Sm 3+ studied by means of thermoluminescence and optical stimulated luminescence techniques. The same samples were studied by pump and probe two photon spectroscopy utilizing synchrotron photons to transfer electrons from Ce 3+ to Ln 3+ defects and 445 nm laser diode to probe the concentration of created Ln 2+.

  9. Total synthesis of natural products using hypervalent iodine reagents

    PubMed Central

    Maertens, Gaëtan; L'Homme, Chloé; Canesi, Sylvain

    2014-01-01

    We present a review of natural product syntheses accomplished in our laboratory during the last 5 years. Each synthetic route features a phenol dearomatization promoted by an environmentally benign hypervalent iodine reagent. The dearomatizations demonstrate the “aromatic ring umpolung” concept, and involve stereoselective remodeling of the inert unsaturations of a phenol into a highly functionalized key intermediate that may contain a quaternary carbon center and a prochiral dienone system. Several new oxidative strategies were employed, including transpositions (1,3-alkyl shift and Prins-pinacol), a polycyclization, an ipso rearrangement, and direct nucleophilic additions at the phenol para position. Several alkaloids, heterocyclic compounds, and a polycyclic core have been achieved, including sceletenone (a serotonin reuptake inhibitor), acetylaspidoalbidine (an antitumor agent), fortucine (antiviral and antitumor), erysotramidine (curare-like effect), platensimycin (an antibiotic), and the main core of a kaurane diterpene (immunosuppressive agent and stimulator of apoptosis). These concise and in some cases enantioselective syntheses effectively demonstrate the importance of hypervalent iodine reagents in the total synthesis of bioactive natural products. PMID:25601909

  10. Total Synthesis of Natural Products Using Hypervalent Iodine Reagents

    NASA Astrophysics Data System (ADS)

    Maertens, Gaetan; L'homme, Chloe; Canesi, Sylvain

    2014-12-01

    We present a review of natural product syntheses accomplished in our laboratory during the last five years. Each synthetic route features a phenol dearomatization promoted by an environmentally benign hypervalent iodine reagent. The dearomatizations demonstrate the “aromatic ring umpolung” concept, and involve stereoselective remodeling of the inert unsaturations of a phenol into a highly functionalized key intermediate that may contain a quaternary carbon center and a prochiral dienone system. Several new oxidative strategies were employed, including transpositions (1,3-alkyl shift and Prins-pinacol), a polycyclization, an ipso rearrangement, and direct nucleophilic additions at the phenol para position. Several alkaloids, heterocyclic compounds, and a polycyclic core have been achieved, including sceletenone (a serotonin reuptake inhibitor), acetylaspidoalbidine (an antitumor agent), fortucine (antiviral and antitumor), erysotramidine (curare-like effect), platensimycin (an antibiotic), and the main core of a kaurane diterpene (immunosuppressive agent and stimulator of apoptosis). These concise and in some cases enantioselective syntheses effectively demonstrate the importance of hypervalent iodine reagents in the total synthesis of bioactive natural products.

  11. Stick shift

    E-print Network

    Parness, Aaron J. (Aaron Joseph), 1981-

    2004-01-01

    Stick Shift is a novel that has undergone several rounds of significant revision. Scott, the book's main character, is a sarcastic American who travels to England to move in with an ex-girlfriend. He experiences all of the ...

  12. High-Temperature Density of Lanthanide-Bearing Silicate Melts

    NASA Astrophysics Data System (ADS)

    Courtial, P.; Dingwell, D.

    2002-12-01

    The lanthanides are of interest in the geosciences, despites usually occurring as minor or trace elements in rock-forming minerals although they can be essential constituents of some minerals. In general, they are partitioned more extremely than major elements making them more sensitive indicators of the petrological processes that occur. Therefore, they are a powerful tool in order to trace the processes involved in the petrogenesis of magmas, in the thermodynamical modelling to accurately predict the crystal-melt phase equilibria in a magma. The development of such models requires a reliable thermodynamic database which includes volumetric data available for both major and trace element oxide liquids.\\Efforts have been made to extend the volumetric database of silicate melts on a variety of multi-component systems for the most naturally abundant oxides. However, experimental data on other significant oxides, such as lanthanides, are lacking. Therefore, in order to fill this gap and to provide a new volumetric dataset, which will allow the available models in the literature to be extended to lanthanide-bearing liquids, we are conducting density measurements on various lanthanide-bearing silicate melts.\\In this paper, we present density measurements obtained in air for various lanthanide-bearing silicate melts (from cerium to lutetium including lanthanum). The present results suggest that the addition of lanthanide leads to an increase in density of the melt. In addition, the melt density at a given lanthanide content increases with increasing atomic number, with the exception of La. This preliminary volumetric dataset allows a first estimation of the partial molar volume of each lanthanide oxide liquids (i.e., the partial molar volumes calculated at 1550 K for the investigated lanthanide oxides range from 15 to 23 cm3/mol for Tm2O3 and Pr6O11, respectively). High-temperature density measurements on new compositions are in progress in order to determine the partial molar volume of lanthanide oxide liquids more accurately.

  13. Phase transition mechanisms in lanthanide elemental crystals

    NASA Astrophysics Data System (ADS)

    Dmitriev, V. P.; Kuznetsov, A. Yu.; Machon, D.; Weber, H.-P.; Tolédano, P.

    2003-03-01

    A unifying theoretical description is given of the phase transition mechanisms occurring in lanthanide elemental crystals. The hcp-9R-dhcp-fcc sequence of reconstructive phase transitions is interpreted in terms of crossover between displacive and reordering mechanisms. The distorted fcc, monoclinic, ?-U-type and bct high-pressure phases can be depicted by purely displacive mechanisms, the low symmetry of these phases resulting from the non-spherical shape of the electronic shells induced by the delocalization of the f-electrons.

  14. Lanthanide Complexes as a Test for Evidence of Life

    NASA Technical Reports Server (NTRS)

    Benavides, Jeannette

    1998-01-01

    The objective of this research is to advance the understanding of the interaction of lanthanide metals with biological organic molecules and to develop a technique to detect these compounds in the solid state and in situ in Mars and other planetary bodies. The detection of these complexes should provide evidence of life past or present. In addition, detection of the metals alone will provide important information about the geological history of a planetary body. Lanthanides were chosen as our focus of interest because they form very stable complexes with organic molecules in solution and they produce intense luminescence in the ultraviolet and visible spectra. The rare earth complexes available are mostly synthetic for diverse applications in medicine. There is not much work done on the complexes that form in nature. Lanthanides have many applications and they are mined aR over the world, however, since the interest has been only in the elements, the analytical techniques employed destroy any organic ligands that may be present. In order to determine if and which lanthanide complexes form in nature and their concentration, soil samples have been collected from areas rich in soluble lanthanide compounds like phosphates and also rich in vegetation. The soil samples will be analyzed and the lanthanide complexes if present will be isolated and characterized. A spectrometer to detect the lanthanide complexes in situ and in the solid state will be designed. In this workshop, the research approach and its implications will be discussed.

  15. Relationship between lanthanide contents in aquatic turtles and environmental exposures.

    PubMed

    Censi, P; Randazzo, L A; D'Angelo, S; Saiano, F; Zuddas, P; Mazzola, S; Cuttitta, A

    2013-05-01

    Trace elements released in the environment during agricultural practices can be incorporated and accumulated in biological fluids and tissues of living organisms. The assessment of these exposures were carried out investigating lanthanide distributions in blood and exoskeleton samples collected from Emys trinacris turtle specimens coming from sites with anthropogenic discharge in western and south Sicily, along migration paths of many bird species from Africa to Europe. The data show a significant (Rxy=0.72; Rxy>0.67; ?=0.025) linear relationship between the size of turtle specimens and the lanthanide contents in blood lower than 0.4 ?g L(-1) whereas this relationship disappears in blood with higher lanthanide contents. Comparative evaluations of normalised concentrations show that lanthanides fractionate between blood and exoskeleton inducing antithetical lanthanide patterns therein. These features are more evident in specimens with high lanthanide contents in blood, suggesting that lanthanide accumulations in the exoskeleton can represent the physiological response of E. trinacris to environmental and the further confirmation of relationship occurring between the environmental and the biological fluids. PMID:23411091

  16. Fluid Shifts

    NASA Technical Reports Server (NTRS)

    Stenger, M. B.; Hargens, A.; Dulchavsky, S.; Ebert, D.; Lee, S.; Laurie, S.; Garcia, K.; Sargsyan, A.; Martin, D.; Lui, J.; Macias, B.; Arbeille, P.; Danielson, R.; Chang, D.; Gunga, H.; Johnston, S.; Westby, C.; Ribeiro, L.; Ploutz-Snyder, R.; Smith, S.

    2015-01-01

    INTRODUCTION: Mechanisms responsible for the ocular structural and functional changes that characterize the visual impairment and intracranial pressure (ICP) syndrome (VIIP) are unclear, but hypothesized to be secondary to the cephalad fluid shift experienced in spaceflight. This study will relate the fluid distribution and compartmentalization associated with long-duration spaceflight with VIIP symptoms. We also seek to determine whether the magnitude of fluid shifts during spaceflight, as well as the VIIP-related effects of those shifts, can be predicted preflight with acute hemodynamic manipulations, and also if lower body negative pressure (LBNP) can reverse the VIIP effects. METHODS: Physiologic variables will be examined pre-, in- and post-flight in 10 International Space Station crewmembers including: fluid compartmentalization (D2O and NaBr dilution); interstitial tissue thickness (ultrasound); vascular dimensions and dynamics (ultrasound and MRI (including cerebrospinal fluid pulsatility)); ocular measures (optical coherence tomography, intraocular pressure, ultrasound); and ICP measures (tympanic membrane displacement, otoacoustic emissions). Pre- and post-flight measures will be assessed while upright, supine and during 15 deg head-down tilt (HDT). In-flight measures will occur early and late during 6 or 12 month missions. LBNP will be evaluated as a countermeasure during HDT and during spaceflight. RESULTS: The first two crewmembers are in the preflight testing phase. Preliminary results characterize the acute fluid shifts experienced from upright, to supine and HDT postures (increased stroke volume, jugular dimensions and measures of ICP) which are reversed with 25 millimeters Hg LBNP. DISCUSSION: Initial results indicate that acute cephalad fluid shifts may be related to VIIP symptoms, but also may be reversible by LBNP. The effect of a chronic fluid shift has yet to be evaluated. Learning Objectives: Current spaceflight VIIP research is described, including novel hardware and countermeasures.

  17. AQUEOUS RELAXATION REAGENTS IN NITROGEN-15 NMR

    EPA Science Inventory

    Electron-nuclear relaxation times T(1)supe's for 15N and 13C in natural abundance are measured for a series of amines in aqueous solution using Gd(III) complexes of a series of polyaminocarboxylate ligands as paramagnetic relaxation reagents (PARRs). The PARRs are classified by t...

  18. Determination of Cellular Cholesterol Content Reagents Needed

    E-print Network

    Pike, Linda J.

    Determination of Cellular Cholesterol Content Reagents Needed: Wako CII Cholesterol CII assay kit solvents using the SpeedVac. 4. Add 1 ml of the Cholesterol CII (Wako) buffer solution and vortex development with cholesterol is stable for incubation periods of up to 60 min. at 37° C. If detecting ent-cholesterol

  19. DEGRADATION OF MTBE INTERMEDIATES USING FENTON'S REAGENT

    EPA Science Inventory

    In a previous study, the chemical oxidation of MTBE at low concentrations in water using the Fenton's reagent (FR) was investigated. At certain reaction conditions the process achieved 99.99% degradation of MTBE but it did not result in complete MTBE mineralization. In the pres...

  20. Supplemental Materials and Methods Proteins and reagents

    E-print Network

    Kowalczykowski, Stephen C.

    . Escherichia coli RecO protein anneals ssDNA complexed with its cognate ssDNA-binding protein: A common stepSupplemental Materials and Methods Proteins and reagents Proteins were purified as described previously: RecA, RecQ, and SSB proteins (Harmon and Kowalczykowski 1998); RecF protein (Morimatsu

  1. USE OF FENTON'S REAGENT AS DISINFECTING AGENT

    EPA Science Inventory

    This project was conducted as an EPA in-house research, assisted by the on-site contractor, US Infrastructure, Inc. (USI) located in Edison, NJ. The Fenton's reagent (e.g., H2O2, ferrous iron Fe(aq)+2) is an alternative method of chemical oxidation. Hydroxyl radicals (OH ), gen...

  2. Tritioacetylating reagents and processes for preparation thereof

    DOEpatents

    Saljoughian, Manoucher (Moraga, CA); Morimoto, Hiromi (El Cerrito, CA); Williams, Philip G. (Oakland, CA); Than, Chit (Lafayette, CA)

    2000-01-01

    Novel acetylating and tritioacetylating reagents suitable for preparation of nonlabelled and radiolabelled organic compounds. N-acetoxynaphthalimide, N-tritioacetoxyphthalimide, N-tritioacetoxysuccinimide, N-tritioacetoxynaphthalimide and processes of their preparation. The invention also concerns synthesis of nonlabelled acetylated and tritioacetylated organic compounds from precursors containing a free --NH.sub.2, --SH or --OH group.

  3. Remarks on preparation of indandione detection reagents

    NASA Technical Reports Server (NTRS)

    Stepan, J.; Kral, V.

    1985-01-01

    A modified Claisen condensation with sliced sodium at a higher temperature was recommended for the production of ungranulated charcoal. A new ninhydrin production method by oxidation of benzaldiketohydrinden using available reagents was tried and was unsuccessful. Triketohydrinden was obtained by boiling ninhydrin in acetic acid anhydrides.

  4. The Crystal Structure of Lanthanide Zirconates

    NASA Astrophysics Data System (ADS)

    Clements, Richard; Kennedy, Brendan; Ling, Christopher; Stampfl, Anton P. J.

    2010-03-01

    The lanthanide zirconates of composition Ln2Zr2O7 (Ln = La-Gd) are of interest for use in inert matrix fuels and nuclear wasteforms. The series undergoes a pyrochlore to fluorite phase transition as a function of the Ln atomic radii. The phase transition has been attributed to disordering of both the cation and the anion [1]. We have undertaken a synthesis of the lanthanide zirconate series Ln2Zr2O7 (Ln = La-Gd), Ln0.2Zr0.8O1.9 (Ln = Tb-Yb) and NdxHo2-xZr2O7 (0

  5. Distribution of Lanthanides in Mediterranean Coastal Water

    NASA Astrophysics Data System (ADS)

    Zuddas, P.; Censi, P.; Mazzola, S.; Arico, P.

    2007-12-01

    Distribution and behaviour of the whole lanthanide series and yttrium in both seawater column and suspended particulate matter were investigated in coastal water located in the Central Mediterranean Sea. An area characterized by high anthropic pressure, atmospheric fallout and river input due to drainage of little local watersheds was selected. Water masses were discriminated with respect to both surrounding and depth and in relation to the processes occurring at the solid-liquid interface. We found that yttrium and Rare Earth Elements in the labile fraction of the suspended particulates result from the mixing between lithogenic material from the Sicilian basin and detrital material of Sahara origin. Y/Ho and Ce/La ratios, Ce anomalies, shape and amplitudes of tetrad effects calculated in both dissolved phase and suspended matter indicates that heavier Rare Earth (from Dy to Lu) mainly occur as organic complexes in near shore waters whereas, light and intermediate Rare Earths (From La to Ho) in the outer waters are ruled by scaveging processes onto surface of suspended matter. The behaviour of these trace elements is explained in terms of lanthanides sorption into Mn-Fe oxyhydroxide surfaces and under solution complexation. In particular, for deep water layers the found low apparent distribution coefficients for the heaviest REE and high dissolved organic matter concentration indicate surface complexation processes according to an outer sphere coordination mechanism.

  6. Lanthanide Complexes of Azidophenacyl-DO3A as New Synthons for Click Chemistry and the Synthesis of Heterometallic Lanthanide Arrays.

    PubMed

    Tropiano, Manuel; Kenwright, Alan M; Faulkner, Stephen

    2015-04-01

    Lanthanide complexes of azidophenacyl DO3A are effective substrates for click reactions with ethyne derivatives, giving rise to aryl triazole appended lanthanide complexes, in which the aryl triazole acts as an effective sensitising chromophore for lanthanide luminescence. They also undergo click chemistry with propargylDO3A derivatives, giving rise to heterometallic complexes. PMID:25754928

  7. 21 CFR 866.3280 - Francisella tularensis serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3280 Francisella tularensis serological reagents....

  8. 21 CFR 864.8950 - Russell viper venom reagent.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8950 Russell viper venom reagent. (a) Identification. Russell viper...

  9. 21 CFR 864.8950 - Russell viper venom reagent.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8950 Russell viper venom reagent. (a) Identification. Russell viper...

  10. 21 CFR 866.3175 - Cytomegalovirus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents ...Cytomegalovirus serological reagents are devices that consist of antigens...infants and is caused by intrauterine or early postnatal...

  11. The Grignard Reagent: Preparation, Structure, and Some Reactions.

    ERIC Educational Resources Information Center

    Orchin, Milton

    1989-01-01

    The Grignard reagent used in the laboratory synthesis of organic compounds is the product resulting from the reaction of an alkyl or aryl halide with elemental magnesium. Describes the structure, formation, and some reactions of the reagent. (YP)

  12. CLAY AND CLAY-SUPPORTED REAGENTS IN ORGANIC SYNTHESES

    EPA Science Inventory

    CLAY AND CLAY-SUPPORTED REAGENTS HAVE BEEN USED EXTENSIVELY FOR SYNTHETIC ORGANIC TRANSFORMATIONS. THIS OVERVIEW DESCRIBES THE SALIENT STRUCTURAL PROPERTIES OF VARIOUS CLAY MATERIALS AND EXTENDS THE DISCUSSION TO PILLARED CLAYS AND REAGENTS SUPPORTED ON CLAY MATERIALS. A VARIET...

  13. A lanthanide salen "square prism" and a wrapped exo-lanthanide salen "double decker".

    PubMed

    Shu, Yu-Bo; Liu, Wei-Sheng

    2015-03-24

    An erbium(iii) salen "square prism" and a supramolecular aggregate of exo-erbium(iii) salen "double-decker" cations wrapped by an anionic cuprous cyanide network were prepared from N,N'-ethylene bis[4-(diethylamino)salicylideneimine. Both erbium(iii) edifices show fine-structure near-infrared (NIR) luminescence under the excitation in the visible light area. Here we provide a novel and efficient method for stabilizing non-isolable lanthanide edifices in the solid state. PMID:25773380

  14. Separation of Minor Actinides from Lanthanides by Dithiophosphinic Acid Extractants

    SciTech Connect

    D. R. Peterman; M. R. Greenhalgh; R. D. Tillotson; J. R. Klaehn; M. K. Harrup; T. A. Luther; J. D. Law; L. M. Daniels

    2008-09-01

    The selective extraction of the minor actinides (Am(III) and Cm(III)) from the lanthanides is an important part of advanced reprocessing of spent nuclear fuel. This separation would allow the Am/Cm to be fabricated into targets and recycled to a reactor and the lanthanides to be dispositioned. This separation is difficult to accomplish due to the similarities in the chemical properties of the trivalent actinides and lanthanides. Research efforts at the Idaho National Laboratory have identified an innovative synthetic pathway yielding new regiospecific dithiophosphinic acid (DPAH) extractants. The synthesis provides DPAH derivatives that can address the issues concerning minor actinide separation and extractant stability. For this work, two new symmetric DPAH extractants have been prepared. The use of these extractants for the separation of minor actinides from lanthanides will be discussed.

  15. Investigation of organosilicon compounds as reagents during coal flotation

    SciTech Connect

    Petykhov, V.N.

    1984-01-01

    Work at Magnitogorsk Metals has confirmed the superiority of certain silico-organic compounds over conventional acetates and ethers as flotation reagents. At the same time, losses of coal in the discard are decreased, and consumption of reagent is diminished. The properties of silico-organic compounds that contribute to their effectiveness as flotation reagents are discussed.

  16. Swine Toolkit Progress for US Veterinary Immune Reagent Network

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The US Veterinary Immune Reagent Network (http://www.umass.edu/vetimm/) was established to address the lack of immunological reagents for veterinary species. Within this context, plans are underway to produce sets of reagents needed to evaluate immune changes during disease and following vaccination...

  17. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30 Food and Drugs...SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition....

  18. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30 Food and Drugs...SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition....

  19. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30 Food and Drugs...SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition....

  20. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30 Food...DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and...

  1. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2010-04-01 true Reagent Red Blood Cells. 660.30 Section 660.30 Food and Drugs...SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition....

  2. A High-Sensitivity Lanthanide Nanoparticle Reporter for Mass Cytometry: Tests on Microgels as a Proxy for Cells

    PubMed Central

    2015-01-01

    This paper addresses the question of whether one can use lanthanide nanoparticles (e.g., NaHoF4) to detect surface biomarkers expressed at low levels by mass cytometry. To avoid many of the complications of experiments on live or fixed cells, we carried out proof-of-concept experiments using aqueous microgels with a diameter on the order of 700 nm as a proxy for cells. These microgels were used to test whether nanoparticle (NP) reagents would allow the detection of as few as 100 proteins per “cell” in cell-by-cell assays. Streptavidin (SAv), which served as the model biomarker, was attached to the microgel in two different ways. Covalent coupling to surface carboxyls of the microgel led to large numbers (>104) of proteins per microgel, whereas biotinylation of the microgel followed by exposure to SAv led to much smaller numbers of SAv per microgel. Using mass cytometry, we compared two biotin-containing reagents, which recognized and bound to the SAvs on the microgel. One was a metal chelating polymer (MCP), a biotin end-capped polyaspartamide containing 50 Tb3+ ions per probe. The other was a biotinylated NaHoF4 NP containing 15?000 Ho atoms per probe. Nonspecific binding was determined with bovine serum albumin (BSA) conjugated microgels. The MCP was effective at detecting and quantifying SAvs on the microgel with covalently bound SAv (20?000 SAvs per microgel) but was unable to give a meaningful signal above that of the BSA-coated microgel for the samples with low levels of SAv. Here the NP reagent gave a signal 2 orders of magnitude stronger than that of the MCP and allowed detection of NPs ranging from 100 to 500 per microgel. Sensitivity was limited by the level of nonspecific adsorption. This proof of concept experiment demonstrates the enhanced sensitivity possible with NP reagents in cell-by-cell assays by mass cytometry. PMID:24617504

  3. Lanthanide binding and IgG affinity construct: Potential applications in solution NMR, MRI, and luminescence microscopy

    PubMed Central

    Barb, Adam W; Ho, Tienhuei Grace; Flanagan-Steet, Heather; Prestegard, James H

    2012-01-01

    Paramagnetic lanthanide ions when bound to proteins offer great potential for structural investigations that utilize solution nuclear magnetic resonance spectroscopy, magnetic resonance imaging, or optical microscopy. However, many proteins do not have native metal ion binding sites and engineering a chimeric protein to bind an ion while retaining affinity for a protein of interest represents a significant challenge. Here we report the characterization of an immunoglobulin G-binding protein redesigned to include a lanthanide binding motif in place of a loop between two helices (Z-L2LBT). It was shown to bind Tb3+ with 130 nM affinity. Ions such as Dy3+, Yb3+, and Ce3+ produce paramagnetic effects on NMR spectra and the utility of these effects is illustrated by their use in determining a structural model of the metal-complexed Z-L2LBT protein and a preliminary characterization of the dynamic distribution of IgG Fc glycan positions. Furthermore, this designed protein is demonstrated to be a novel IgG-binding reagent for magnetic resonance imaging (Z-L2LBT:Gd3+ complex) and luminescence microscopy (Z-L2LBT: Tb3+ complex). PMID:22851279

  4. Lanthanide ions as required cofactors for DNA catalysts

    PubMed Central

    Dokukin, Victor

    2012-01-01

    We report that micromolar concentrations of lanthanide ions can be required cofactors for DNA-hydrolyzing deoxyribozymes. Previous work identified deoxyribozymes that simultaneously require both Zn2+ and Mn2+ to achieve DNA-catalyzed DNA hydrolysis (1012 rate enhancement); a mutant of one such DNA catalyst requires only Zn2+. Here we show that in vitro selection in the presence of 10 µM lanthanide ion (Ce3+, Eu3+, or Yb3+) along with 1 mM Zn2+ leads to numerous DNA-hydrolyzing deoxyribozymes that strictly require the lanthanide ion as well as Zn2+ for catalytic activity. These DNA catalysts have a range of lanthanide dependences, including some deoxyribozymes that strongly favor one particular lanthanide ion (e.g., Ce3+ >> Eu3+ >> Yb3+) and others that function well with more than one lanthanide ion. Intriguingly, two of the Yb3+-dependent deoxyribozymes function well with Yb3+ alone (Kd,app ~10 µM, in the absence of Zn2+) and have little or no activity with Eu3+ or Ce3+. In contrast to these selection outcomes when lanthanide ions were present, new selections with Zn2+ or Mn2+ alone, or Zn2+ with Mg2+/Ca2+, led primarily to deoxyribozymes that cleave DNA by deglycosylation and ?-elimination rather than by hydrolysis, including several instances of depyrimidination. We conclude that lanthanide ions warrant closer attention as cofactors when identifying new nucleic acid catalysts, especially for applications in which high concentrations of polyvalent metal ion cofactors are undesirable. PMID:23243490

  5. Lighting up cells with lanthanide self-assembled helicates

    PubMed Central

    Bünzli, Jean-Claude G.

    2013-01-01

    Lanthanide bioprobes and bioconjugates are ideal luminescent stains in view of their low propensity to photobleaching, sharp emission lines and long excited state lifetimes permitting time-resolved detection for enhanced sensitivity. We show here how the interplay between physical, chemical and biochemical properties allied to microfluidics engineering leads to self-assembled dinuclear lanthanide luminescent probes illuminating live cells and selectively detecting biomarkers expressed by cancerous human breast cells. PMID:24511387

  6. Fluid Shifts

    NASA Technical Reports Server (NTRS)

    Stenger, Michael; Hargens, A.; Dulchavsky, S.; Ebert, D.; Lee, S.; Sargsyan, A.; Martin, D.; Lui, J.; Macias, B.; Arbeille, P.; Platts, S.

    2014-01-01

    NASA is focusing on long-duration missions on the International Space Station (ISS) and future exploration-class missions beyond low Earth orbit. Visual acuity changes observed after short-duration missions were largely transient, but more than 30% of ISS astronauts experience more profound, chronic changes with objective structural and functional findings such as papilledema and choroidal folds. Globe flattening, optic nerve sheath dilation, and optic nerve tortuosity also are apparent. This pattern is referred to as the visual impairment and intracranial pressure (VIIP) syndrome. VIIP signs and symptoms, as well as postflight lumbar puncture data, suggest that elevated intracranial pressure (ICP) may be associated with the space flight-induced cephalad fluid shifts, but this hypothesis has not been tested. The purpose of this study is to characterize fluid distribution and compartmentalization associated with long-duration space flight, and to correlate these findings with vision changes and other elements of the VIIP syndrome. We also seek to determine whether the magnitude of fluid shifts during space flight, as well as the VIIP-related effects of those shifts, is predicted by the crewmember's pre-flight condition and responses to acute hemodynamic manipulations (such as head-down tilt). Lastly, we will evaluate the patterns of fluid distribution in ISS astronauts during acute reversal of fluid shifts through application of lower body negative pressure (LBNP) interventions to characterize and explain general and individual responses. We will examine a variety of physiologic variables in 10 long-duration ISS crewmembers using the test conditions and timeline presented in the Figure below. Measures include: (1) fluid compartmentalization (total body water by D2O, extracellular fluid by NaBr, intracellular fluid by calculation, plasma volume by CO rebreathe, interstitial fluid by calculation); (2) forehead/eyelids, tibia, calcaneus tissue thickness (by ultrasound); (3) vascular dimensions by ultrasound (jugular veins, cerebral and carotid arteries, vertebral arteries and veins, portal vein); (4) vascular dynamics by MRI (head/neck blood flow, cerebrospinal fluid pulsatility); (5) ocular measures (optical coherence tomography, intraocular pressure, 2-dimensional ultrasound including optic nerve sheath diameter, globe flattening, and retina-choroid thickness, Doppler ultrasound of ophthalmic and retinal arteries, and veins); (6) cardiac variables by ultrasound (inferior vena cava, tricuspid flow and tissue Doppler, pulmonic valve, stroke volume, right heart dimensions and function, four-chamber views); and (7) ICP measures (tympanic membrane displacement, distortion-product otoacoustic emissions, and ICP calculated by MRI). On the ground, acute head-down tilt will induce cephalad fluid shifts, whereas LBNP will oppose these shifts. Controlled Mueller maneuvers will manipulate cardiovascular variables. Through interventions applied before, during, and after flight, we intend to fully evaluate the relationship between fluid shifts and the VIIP syndrome. This study has been selected for flight implementation and is one of the candidate investigations being considered for the one year mission.

  7. Treatment of textile wastewater by Fenton's reagent

    Microsoft Academic Search

    S. H. Lin; C. F. Peng

    1995-01-01

    Treatment of textile wastewaters from a dyeing and finishing mill by Fenton's reagent is investigated. The experimental results are assessed in terms of COD and color (turbidity) reductions to determine the treatment efficiency of the Fenton's process. Operating variables, such as the pH, amounts of H2O2 and FeSO4, time of Fenton's treatment and amounts of polyaluminum chloride (PAC) and polymer,

  8. Lanthanide coordination polymers: Synthesis, diverse structure and luminescence properties

    NASA Astrophysics Data System (ADS)

    Song, Xue-Qin; Lei, Yao-Kun; Wang, Xiao-Run; Zhao, Meng-Meng; Peng, Yun-Qiao; Cheng, Guo-Quan

    2014-10-01

    The new semirigid exo-bidentate ligand incorporating furfurysalicylamide terminal groups, namely, 1,4-bis{[(2?-furfurylaminoformyl)phenoxyl]methyl}-2,5-bismethylbenzene (L) was synthesized and used as building blocks for constructing lanthanide coordination polymers with luminescent properties. The series of lanthanide nitrate complexes have been characterized by elemental analysis, IR spectroscopy, and X-ray diffraction analysis. The semirigid ligand L, as a bridging ligand, reacts with lanthanide nitrates forming three distinct structure types: chiral noninterpenetrated two-dimensional (2D) honeycomblike (6,3) (hcb, Schläfli symbol 63, vertex symbol 6 6 6) topological network as type I, 1D zigzag chain as type II and 1D trapezoid ladder-like chain as type III. The structural diversities indicate that lanthanide contraction effect played significant roles in the structural self-assembled process. The luminescent properties of EuIII, TbIII and DyIII complexes are discussed in detail. Due to the good match between the lowest triplet state of the ligand and the resonant energy level of the lanthanide ion, the lanthanide ions in EuIII, TbIII and DyIII complexes can be efficiently sensitized by the ligand.

  9. Organophosphazenes. 26. Factors controlling the pathways observed in the reactions of ethynyl lithium reagents with hexafluorocyclotriphosphazene.

    PubMed

    Bahadur, Maneesh; Allen, Christopher W

    2012-05-01

    In contrast to previously studied reactions of ethynyl lithium reagents, the reactions of propynyl and hexynyl lithium with N(3)P(3)F(6) lead to predominantly nongeminal isomers. A modest cis stereo selectivity was observed. The sequential addition of a lithio acetylene reagent which follows a predominately geminal pathway (lithiophenylacetylene) and an aryl lithium reagent (p-propenylphenyl lithium) which follows a predominantly nongeminal pathway were examined. The relative order of addition of the two reagents was interchanged, resulting in a change of reaction pathway demonstrating ring substituent control of the regio and stereo chemical pathways. Hydrogenation of the ethynyl unit in the phosphazene derivatives provides a facile pathway to the difficult to prepare alkylphosphazenes. The chemical shift of the organosubstituted phosphorus center undergoes a remarkably large change (46-47 ppm) on going from the ethynyl to the alkyl derivatives, which reduces the complex (31)P and (19)F NMR spectra of the ethynyl derivatives to easily interpretable first-order spectra, thus allowing for structure assignment. The (13)C NMR data shows that nongeminal regio selectivity increases with the amount of s character on the ethynyl carbon atom attached to the phosphorus center. These observations allow for an understanding of the factors controlling regio and stereo chemical control in the reactions of carbanionic nucleophiles with N(3)P(3)F(6). PMID:22497603

  10. The biosafety of lanthanide upconversion nanomaterials.

    PubMed

    Sun, Yun; Feng, Wei; Yang, Pengyuan; Huang, Chunhui; Li, Fuyou

    2015-03-10

    Lanthanide upconversion nanophosphors (UCNPs) show unique upconversion luminescence where lower-energy photons (such as near-infrared (NIR) excitation) are converted into higher-energy photons covering the NIR to the UV region, and are considered to have a bright future in clinical translation. As UCNPs are used in a significant number of potential bio-applications, their biosafety is important and has attracted significant attention. In this critical review, recent reports regarding the cellular internalization, biodistribution, excretion, cytotoxicity and in vivo toxic effects of UCNPs are reviewed. In particular, the studies which evaluated the association between the chemical and physical properties of UCNPs and their biodistribution, excretion, and toxic effects are presented in detail. Finally, we also discuss the challenges of ensuring the biosafety of UCNPs in vivo. PMID:25113504

  11. Tough photoluminescent hydrogels doped with lanthanide.

    PubMed

    Wang, Mei Xiang; Yang, Can Hui; Liu, Zhen Qi; Zhou, Jinxiong; Xu, Feng; Suo, Zhigang; Yang, Jian Hai; Chen, Yong Mei

    2015-03-01

    Photoluminescent hydrogels have emerged as novel soft materials with potential applications in many fields. Although many photoluminescent hydrogels have been fabricated, their scope of usage has been severely limited by their poor mechanical performance. Here, a facile strategy is reported for preparing lanthanide (Ln)-alginate/polyacrylamide (PAAm) hydrogels with both high toughness and photoluminescence, which has been achieved by doping Ln(3+) ions (Ln = Eu, Tb, Eu/Tb) into alginate/PAAm hydrogel networks, where Ln(3+) ions serve as both photoluminescent emitters and physical cross-linkers. The resulting hydrogels exhibit versatile advantages including excellent mechanical properties (?MPa strength, ?20 tensile strains, ?10(4) kJ m(-3) energy dissipation), good photoluminescent performance, tunable emission color, excellent processability, and cytocompatibility. The developed tough photoluminescent hydrogels hold great promises for expanding the usage scope of hydrogels. PMID:25605548

  12. 21 CFR 866.3235 - Epstein-Barr virus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Epstein-Barr virus serological reagents. 866.3235 Section...Reagents § 866.3235 Epstein-Barr virus serological reagents. (a) Identification. Epstein-Barr virus serological reagents are devices...

  13. 21 CFR 866.3900 - Varicella-zoster virus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Varicella-zoster virus serological reagents. 866.3900 ...Reagents § 866.3900 Varicella-zoster virus serological reagents. (a) Identification. Varicella-zoster virus serological reagents are...

  14. 21 CFR 866.3900 - Varicella-zoster virus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Varicella-zoster virus serological reagents. 866.3900 ...Reagents § 866.3900 Varicella-zoster virus serological reagents. (a) Identification. Varicella-zoster virus serological reagents are...

  15. 21 CFR 866.3235 - Epstein-Barr virus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Epstein-Barr virus serological reagents. 866.3235 Section...Reagents § 866.3235 Epstein-Barr virus serological reagents. (a) Identification. Epstein-Barr virus serological reagents are devices...

  16. 21 CFR 866.3900 - Varicella-zoster virus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Varicella-zoster virus serological reagents. 866.3900 ...Reagents § 866.3900 Varicella-zoster virus serological reagents. (a) Identification. Varicella-zoster virus serological reagents are...

  17. 21 CFR 866.3900 - Varicella-zoster virus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Varicella-zoster virus serological reagents. 866.3900 ...Reagents § 866.3900 Varicella-zoster virus serological reagents. (a) Identification. Varicella-zoster virus serological reagents are...

  18. 21 CFR 866.3235 - Epstein-Barr virus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Epstein-Barr virus serological reagents. 866.3235 Section...Reagents § 866.3235 Epstein-Barr virus serological reagents. (a) Identification. Epstein-Barr virus serological reagents are devices...

  19. 21 CFR 866.3235 - Epstein-Barr virus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Epstein-Barr virus serological reagents. 866.3235 Section...Reagents § 866.3235 Epstein-Barr virus serological reagents. (a) Identification. Epstein-Barr virus serological reagents are devices...

  20. 21 CFR 866.3720 - Streptococcus spp. exo-enzyme reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Streptococcus spp. exo-enzyme reagents. ...Serological Reagents § 866.3720 Streptococcus spp. exo-enzyme reagents. (a) Identification. Streptococcus spp. exoenzyme reagents...

  1. Spectroscopic analysis of ligand binding to lanthanide-macrocycle platforms.

    PubMed

    Kirby, James P; Cable, Morgan L; Levine, Dana J; Gray, Harry B; Ponce, Adrian

    2008-08-01

    A high-affinity, binary Eu(3+) receptor site consisting of 1,4,7,10-tetraazacyclododecane-1,7-diacetate (DO2A) was constructed with the goal of improving the detection of dipicolinic acid (DPA), a major component of bacterial spores. Ternary Eu(DO2A)(DPA)(-) complex solutions (1.0 microM crystallographically characterized TBA x Eu(DO2A)(DPA)) were titrated with EuCl3 (1.0 nM-1.0 mM); increased Eu(3+) concentration resulted in a shift in equilibrium population from Eu(DO2A)(DPA)(-) to Eu(DO2A)(+) and Eu(DPA)(+), which was monitored via the ligand field sensitive (5)D0 --> (7)F3 transition (lambda(em) = 670-700 nm) using luminescence spectroscopy. A best fit of luminescence intensity titration data to a two-state thermodynamic model yielded the competition equilibrium constant (Kc), which in conjunction with independent measurement of the Eu(DPA)(+) formation constant (Ka) allowed calculation of the ternary complex formation constant (Ka'). With this binding affinity by competition (BAC) assay, we determined that Ka' = 10(8.21) M(-1), which is approximately 1 order of magnitude greater than the formation of Eu(DPA)(+). In general, the BAC assay can be employed to determine ligand binding constants of systems where the lanthanide platform (usually a binary complex) is stable and the ligand bound versus unbound states can be spectroscopically distinguished. PMID:18578548

  2. Luminescence of Lanthanide-Dimethyl Sulfoxide Compound Solutions

    SciTech Connect

    Yao, Mingzhen; Li, Yuebin; Hossu, Marius; Joly, Alan G.; Liu, Zhongxin; Liu, Zuli; Chen, Wei

    2011-08-04

    Dimethyl sulfoxide (DMSO) has the ability to penetrate living tissues without causing significant damage. Of foremost importance to our understanding of the possible functions of DMSO in biological systems is its ability to replace some of the water molecules associated with the cellular constituents, or to affect the structure of the omnipresent water. Luminescence probes have been widely used for biological studies such as labeling, imaging and detection. Luminescence probes formed in DMSO may find new applications. Here, luminescence compounds formed by refluxing lanthanide nitrates of Ce, La, Tb, Yb, Nd, Gd and Eu in DMSO are reported and their luminescence properties investigated. Based on their luminescence spectral properties, the compounds can be classified into four classes. For compounds-I with Yb, Ce, and La, the excitation and emission spectra are very broad and their excitation or emission peaks are shifted to longer wavelengths when the monitored emission or excitation wavelength is longer . For compounds-II with Gd and Nd, both the excitation and emission spectra are very broad but their emission wavelengths change little at different excitation wavelengths. For Tb-DMSO as compound-III, both the typical emissions from the f - f transitions of Tb3+ and a broad emission at 445 nm are observed. At low temperatures of reaction, the f - f emissions are dominant, while at high temperatures such as 180 oC of reaction, the broad emission at 445 nm is dominant. For compound-IV with Eu-DMSO compounds, the dominant emissions are from the f - f transitions of Eu3+ and only a weak broad emission is observed, which is likely from the d - f transition of Eu2+ rather than from the metal to ligand charge transfer states.

  3. Optical properties of lanthanide dyes for spectral conversion encapsulated in porous silica nanoparticles

    NASA Astrophysics Data System (ADS)

    Pizzol, Paolo; Marques-Hueso, Jose; Robertson, Neil; Freris, Isidora; Bellotto, Luca; Meyer, Thomas J. J.; Richards, Bryce S.

    2012-06-01

    Lanthanide based dyes belong to one of the most promising fields of photovoltaic research, combining high quantum yields and large spectral shift. However, many challenges are faced when working with lanthanide dyes for spectral conversion: their thermal and chemical stability, which can greatly influence the shelf-life of the dyes; the absorption band position, which depends on the organic part of the dye, the so called "antenna" self-quenching mechanisms, which lead to a photoluminescence emission loss. The chemical composition of the surrounding environment of the dyes has a fundamental role in their properties. In this paper, the optical and PLQY (photoluminescence quantum yield) properties of an europium-based dye embedded in a silica matrix are reported. The in-house synthesized dye consists of a bis(2- (diphenylphosphino)phenyl)ether oxide (DPEPO) ligand and three hexafluoroacetylacetonate (hfac) co-ligands coordinating a central europium ion. The dye has been included in porous core-shell particles, to study its optical properties once embedded in a solid dielectric matrix. The optical properties of the resulting samples have been characterized by photoluminescence emission and PLQY measurements. The results have been compared with data obtained from a commercially available dye (BASF Lumogen family) in similar conditions.

  4. {sup 31}P NMR study of the complexation of TBP with lanthanides and actinides in solution and in a clay matrix

    SciTech Connect

    Hartzell, C.J. [Northern Arizona Univ., Flagstaff, AZ (United States)

    1994-07-24

    Goal was to use NMR to study TBP/lanthanide complexes in the interlayer or on edge sites of clays. Work in this laboratory yielded details of the complexation of Eu(NO{sub 3}){sub 3} and Pr(NO{sub 3}){sub 3} with TBP in hexane solution; this information is crucial to interpretation of results of NMR studies of the complexes exchanged into clays. The solution {sup 31}P-chemical shift values were improved by repeating the studies on the lanthanide salts dissolved directly into neat TBP. NMR studies of these neat solutions of the Eu(NO{sub 3}){sub 3}{lg_bullet}3TBP-complex and the Pr(NO{sub 3}){sub 3}{lg_bullet}3TBP-complex show that the {sup 31}P chemical shift remains relatively constant for TBP: lanthanide ratios below 3: 1. At higher ratios, the chemical shift approaches that of free TBP, indicating rapid exchange of TBP between the free and complexed state. Exchange of these complexes into the clay hectorite yielded discrete {sup 31}P-NMR signals for the Eu{lg_bullet}TBP complex at -190 ppm and free TBP at -6 ppm. Adsorption of the Pr{lg_bullet}TBP complex yielded broad signals at 76 ppm for the complex and -6 ppm for free TBP. There was no evidence of exchange between the incorporated complex and the free TBP.

  5. Shelf-stable electrophilic trifluoromethylating reagents: A brief historical perspective

    PubMed Central

    Matsnev, Andrej

    2010-01-01

    Summary Since the discovery by Yagupolskii and co-workers that S-trifluoromethyl diarylsulfonium salts are effective for the trifluoromethylation of thiophenolates, the design and synthesis of electrophilic trifluoromethylating reagents have been extensively researched in both academia and industry, due to the significant unique features that trifluoromethylated compounds have in pharmaceuticals, agricultural chemicals, and functional materials. Several effective reagents have been developed by the groups of Yagupolskii, Umemoto, Shreeve, Adachi, Magnier, Togni and Shibata. Due to the high stability and reactivity of these reagents, a series of Umemoto reagents, Togni reagent and Shibata reagent are now commercially available. In this review, we wish to briefly provide a historical perspective of the development of so-called “shelf-stable electrophilic trifluoromethylating reagents”, although this field is in constant development. PMID:20703379

  6. Separation of Lanthanide Ions with Kläui Ligand Resin

    SciTech Connect

    Granger, Trinity D.; Henry, Victoria A.; Latesky, Stanley

    2007-07-01

    Separation and pre-concentration of the desired analyte is often a critical step in many radioanalytical methods. Current procedures for separating and concentrating analytes for detection are complex, and can be both expensive and time consuming. Therefore, the purpose of this research is to develop an alternative method of separating lanthanide ions through the use of an extraction chromatography resin containing a Klaui ligand salt. This research is a continuation of a concerted effort to develop new methods of detecting small concentrations of radionuclides and lanthanides using Klaui ligands. The Klaui ligands, C5Me5Co(OP(OR)2)3- (R=Me, Et, n-Pr) (LOR-), have unique affinity for lanthanide and actinide ions in the presence of competing metal ions. The use of 1 wt% NaLOR (R=Et or n-Pr) adsorbed onto resin support has been shown to extract lanthanide ions from aqueous nitric acid solutions of different concentrations. In order to further evaluate the utility of these materials in radiochemical separation, the selectivity of the resins for the different lanthanide ions was examined by measuring the distribution coefficients (Kd) for a series of lanthanides over a range of solution conditions. Based on prior research with actinide ions, it was hypothesized that the lanthanide ions would bond strongly with the Klaui ligands. The success of this research is important, because it will assist in expanding and improving current automated radiochemical methods, which will decrease the cost of developing and implementing radiochemical methods. To date, Kd values have been determined for Eu+3, Nd+3 and Pr+3 under varying nitric acid (HNO3) concentration, using a resin consisting of 1.0 wt% NaLOPr on Amberlite XAD-7HP. The dependence of the Kd values for Eu+3 has also been examined as a function of the ligand-to-europium ratio and the nitrate concentration. Decreasing Kd values were obtained upon increasing the nitric acid concentration, indicating protonation of the ligand, which competes with binding of the lanthanide ions. As expected, increasing the Klaui ligand-to-europium ratio results in increasing Kd, but no conclusions could be made from these data regarding stoichiometry of the complex formed on the resin. No dependence of the Kd on the nitrate concentration was observed, supporting the notion that the HNO3 dependence is dominated by the presence of the acidic hydronium ion (as opposed to the nitrate ion). Future work will involve the determination of the Kd values for the remainder of the lanthanide series to further assess the potential of the Klaui ligand for intra-group lanthanide separations.

  7. High-pressure X-ray diffraction studies of light lanthanides 

    E-print Network

    Evans, Shaun Russell

    2010-11-25

    The (trivalent) lanthanides exhibit a common sequence of phases upon the application of pressure: hcp ? dhcp ? fcc ? “distorted-fcc”. The “distorted-fcc”’ phase (d-fcc), observed in the light lanthanides is known to be ...

  8. Methods and apparatuses for reagent delivery, reactive barrier formation, and pest control

    Microsoft Academic Search

    Tyler Gilmore; Daniel I. Kaplan; George Last

    2002-01-01

    A reagent delivery method includes positioning reagent delivery tubes in contact with soil. The tubes can include a wall that is permeable to a soil-modifying reagent. The method further includes supplying the reagent in the tubes, diffusing the reagent through the permeable wall and into the soil, and chemically modifying a selected component of the soil using the reagent. The

  9. Lanthanide accumulation in the periplasmic space of Escherichia coli B.

    PubMed Central

    Bayer, M E; Bayer, M H

    1991-01-01

    Treatment of growing Escherichia coli B with lanthanide ions [lanthanum(III), terbium(III), and europium(III)] and subsequent aldehyde-OsO4 fixation caused areas of high contrast to appear within the periplasm (the space between inner and outer membrane of the cell envelope). X-ray microanalysis of ultrathin sections of Epon-embedded or acrylic resin-embedded cells revealed the presence of the lanthanide and of phosphorus in the areas, whose contrast greatly exceeded that of other stained structures. Comparatively small amounts of the lanthanide were also present in the outer membrane and in the cytoplasm. The distribution of the periplasmic areas of high contrast was found to be random and not clustered at areas of current or future septum formation. Irregular cell shapes were observed after lanthanide treatment before onset of fixation. In contrast to glutaraldehyde-OsO4 fixation, glutaraldehyde used as the sole fixer caused a scattered distribution of the lanthanide. Cryofixation (slam-freezing) and freeze substitution revealed a lanthanum stain at both the periplasm and the outer part of the outer membrane. Deenergization of the cell membrane by either phage T4 or carbonyl cyanide m-chlorophenylhydrazone abolished the metal accumulation. Furthermore, addition of excess calcium, administered together with the lanthanide solution, diminished the quantity and size of areas of high contrast. Cells grown in media of high NaCl concentration revealed strongly stained areas of periplasmic precipitates, whereas cells grown under low-salt conditions showed very few high-contrast patches in the periplasm. Terbium treatment (during fixation) enhanced the visibility of the sites of inner-outer membrane contact (the membrane adhesion sites) in plasmolized cells, possibly as the result of an accumulation of the metal at the adhesion domains. The data suggest a rapid interaction of the lanthanides with components of the cell envelope, the periplasm, and the energized inner membrane. Images PMID:1987113

  10. Lanthanide Borohydrido Complexes for MMA Polymerisation : Syndio-versus Iso-Stereocontrol

    E-print Network

    Paris-Sud XI, Université de

    1 Lanthanide Borohydrido Complexes for MMA Polymerisation : Syndio- versus Iso- Stereocontrol of the polymerisation of MMA with borohydrido lanthanide complexes for the first time. Catalytic systems are made : lanthanides, borohydride, MMA polymerisation, PMMA, tacticity hal-00105931,version1-13Oct2006 #12;3 1

  11. A Simple Empirical Analysis of the Enthalpies of Formation of Lanthanide Halides and Oxides.

    ERIC Educational Resources Information Center

    Smith, Derek W.

    1986-01-01

    Proposes a simple and general method whereby the lattice energies of lanthanide(II) and (IV) compounds are derived directly from those found experimentally for the corresponding lanthanide(III) compounds. The method is applicable to all lanthanide halides and oxides and involves calculations which can be easily and quickly performed by students.…

  12. Facile Oxidative Rearrangements Using Hypervalent Iodine Reagents

    PubMed Central

    Singh, Fateh V; Rehbein, Julia; Wirth, Thomas

    2012-01-01

    Aromatic substituents migrate in a novel oxidative cyclization mediated by iodine(III) reagents. 4-Arylbut-3-enoic acids are cyclized and rearranged to 4-arylfuran-2(5H)-ones by hypervalent iodine compounds in good to excellent yields under mild reaction conditions. Other ring sizes are also accessible. The mechanism of the reaction is described in detail, and calculations highlight the cationic nature of the intermediates in the rearrangement. The fast access to heavily substituted furanones is used for the synthesis of biologically active derivatives. PMID:24551514

  13. Lanthanide(III) complexes with a reinforced cyclam ligand show unprecedented kinetic inertness.

    PubMed

    Rodríguez-Rodríguez, Aurora; Esteban-Gómez, David; Tripier, Raphaël; Tircsó, Gyula; Garda, Zoltán; Tóth, Imre; de Blas, Andrés; Rodríguez-Blas, Teresa; Platas-Iglesias, Carlos

    2014-12-31

    Lanthanide(III) complexes of a cross-bridged cyclam derivative containing two picolinate pendant arms are kinetically inert in very harsh conditions such as 2 M HCl, with no dissociation being observed for at least 5 months. Importantly, the [Ln(dota)](-) complexes, which are recognized to be extremely inert, dissociate under these conditions with lifetimes in the range ca. 1 min to 12 h depending upon the Ln(3+) ion. X-ray diffraction studies reveal octadentate binding of the ligand to the metal ion in the [Eu(cb-tedpa)](+) complex, while (1)H and (13)C NMR experiments in D2O point to the presence of a single diastereoisomer in solution with a very rigid structure. The structure of the complexes in the solid state is retained in solution, as demonstrated by the analysis of the Yb(3+)-induced paramagnetic shifts. PMID:25495928

  14. Purification of lanthanides for large neutrino detectors: Thorium removal from gadolinium chloride

    NASA Astrophysics Data System (ADS)

    Yeh, M.; Cumming, J. B.; Hans, S.; Hahn, R. L.

    2010-06-01

    Metal-loaded liquid scintillators are the detectors of choice for various neutrino experiments. Procedures have been developed to transfer metals into organic liquids by solvent extraction or direct dissolution of a metallic compound. Traces of natural radioactivity introduced into the scintillator with the metal may produce undesirable backgrounds. Measurements using a 229Th tracer indicate that the inclusion of a pH-controlled partial hydrolysis and filtration prior to the preparation of a gadolinium-loading compound can reduce thorium by a factor of ˜100. This "self-scavenging" procedure has the advantage that it uses only reagents encountered in the production process. Addition of non-elemental scavengers such as iron, or the use of solvent extraction or ion exchange procedures can be avoided. It also improves the optical transmission in the blue region by removing traces of iron. This purification method has potential applications to the large-scale production of other metal-loaded liquid scintillators and for the removal of traces of thorium in the industrial production of lanthanides.

  15. Purificaiton of Lanthanides for Large Neutrino Detectors: Thorium Removal from Gadolinium Chloride

    SciTech Connect

    Yeh, M.; Cumming, J.B.; Hans, S.; Hahn, R.L.

    2010-06-01

    Metal-loaded liquid scintillators are the detectors of choice for various neutrino experiments. Procedures have been developed to transfer metals into organic liquids by solvent extraction or direct dissolution of a metallic compound. Traces of natural radioactivity introduced into the scintillator with the metal may produce undesirable backgrounds. Measurements using a {sup 229}Th tracer indicate that the inclusion of a pH-controlled partial hydrolysis and filtration prior to the preparation of a gadolinium-loading compound can reduce thorium by a factor of {approx}100. This 'self-scavenging' procedure has the advantage that it uses only reagents encountered in the production process. Addition of non-elemental scavengers such as iron, or the use of solvent extraction or ion exchange procedures can be avoided. It also improves the optical transmission in the blue region by removing traces of iron. This purification method has potential applications to the large-scale production of other metal-loaded liquid scintillators and for the removal of traces of thorium in the industrial production of lanthanides.

  16. From Antenna to Assay: Lessons Learned in Lanthanide Luminescence

    SciTech Connect

    Moore, Evan; Samuel, Amanda; Raymond, Kenneth

    2008-09-25

    Ligand-sensitized luminescent lanthanide(III) complexes are of considerable current interest due to their unique photophysical properties (micro- to millisecond lifetimes, characteristic and narrow emission bands, and large Stokes shifts), which make them well suited to serve as labels in fluorescence-based bioassays. The long-lived Ln(III) emission can be temporally resolved from scattered light and background fluorescence, resulting in vastly enhanced measurement sensitivity. One of the challenges in this field is the design of sensitizing ligands that provide highly emissive Ln(III) complexes that also possess sufficient stability and aqueous solubility required for practical applications. In this account we give an overview of some of the general properties of the trivalent lanthanides and follow with a summary of advances made in our laboratory in the development of highly luminescent Tb(III) and Eu(III) complexes for applications in biotechnology. A focus of our research has been the optimization of these compounds as potential commercial agents for use in Homogeneous Time Resolved Fluorescence (HTRF) technology, the requirements and current use of which will be briefly discussed. Our approach involves developing high-stability octadentate Tb(III) and Eu(III) complexes that rely on all-oxygen donor atoms as well as using multi-chromophore chelates to increase molar absorptivity compared to earlier examples that utilize a single pendant antenna chromophore. We have found that ligands based on 2-hydroxyisophthalamide (IAM) provide exceptionally emissive Tb(III) complexes with quantum yield values up to ca. 60%. Solution thermodynamic studies have indicated that these complexes are stable at the nanomolar concentrations required for commercial assays. Through synthetic modification of the IAM-chromophore, in conjunction with time-dependent density functional theory (TD-DFT) calculations, we have developed a method to predict absorption and emission properties of these chromophores as a tool to guide ligand design. Additionally we have investigated chiral IAM ligands that yield Tb(III) complexes possessing both high quantum yield values and strong circularly polarized luminescence (CPL) activity. To efficiently sensitize Eu(III) emission, we have utilized ligands based on the 1-hydroxypyridin-2-one (1,2-HOPO) chelate, which are remarkable since they combine both excellent photophysical properties in addition to exceptional aqueous stabilities. A more compete understanding of this chromophore has been achieved by combining low temperature phosphorescence measurements with the same TD-DFT approach used with the IAM system. Also, Eu(III) complexes with strong CPL activity have been obtained through preparation of chiral 1,2-HOPO ligands. Using the unique spectroscopic properties of Eu(III), we have also undertaken the kinetic analysis of radiative and non-radiative decay pathways for a series of complexes, which has highlighted the importance of the metal ion symmetry on the ensuing photophysical properties. Lastly, the commercial development of a Tb-IAM compound that offers improved performance in the common HTRF platform and has the potential to vastly improve the sensitivity of measurements carried out using this technique is presented.

  17. Lanthanide-doped hollow nanomaterials as theranostic agents.

    PubMed

    Kang, Xiaojiao; Li, Chunxia; Cheng, Ziyong; Ma, Ping'an; Hou, Zhiyao; Lin, Jun

    2014-01-01

    The field of theranostics has sprung up to achieve personalized medicine. The theranostics fuses diagnostic and therapeutic functions, empowering early diagnosis, targeted drug delivery, and real-time monitoring of treatment effect into one step. One particularly attractive class of nanomaterials for theranostic application is lanthanide-doped hollow nanomaterials (LDHNs). Because of the existence of lanthanide ions, LDHNs show outstanding fluorescent and paramagnetic properties, enabling them to be used as multimodal bioimaging agents. Synchronously, the huge interior cavities of LDHNs are able to be applied as efficacious tools for storage and delivery of therapeutic agents. The LDHNs can be divided into two types based on difference of component: single-phase lanthanide-doped hollow nanomaterials and lanthanide-doped hollow nanocomposites. We describe the synthesis of first kind of nanomaterials by use of hard template, soft template, template-free, and self-sacrificing template method. For lanthanide-doped hollow nanocomposites, we divide the preparation strategies into three kinds (one-step, two-step, and multistep method) according to the synthetic procedures. Furthermore, we also illustrate the potential bioapplications of these LDHNs, including biodetection, imaging (fluorescent imaging and magnetic resonance imaging), drug/gene delivery, and other therapeutic applications. PMID:24227795

  18. Shifting sugars and shifting paradigms.

    PubMed

    Siegal, Mark L

    2015-02-01

    No organism lives in a constant environment. Based on classical studies in molecular biology, many have viewed microbes as following strict rules for shifting their metabolic activities when prevailing conditions change. For example, students learn that the bacterium Escherichia coli makes proteins for digesting lactose only when lactose is available and glucose, a better sugar, is not. However, recent studies, including three PLOS Biology papers examining sugar utilization in the budding yeast Saccharomyces cerevisiae, show that considerable heterogeneity in response to complex environments exists within and between populations. These results join similar recent results in other organisms that suggest that microbial populations anticipate predictable environmental changes and hedge their bets against unpredictable ones. The classical view therefore represents but one special case in a range of evolutionary adaptations to environmental changes that all organisms face. PMID:25688600

  19. Shifting Sugars and Shifting Paradigms

    PubMed Central

    Siegal, Mark L.

    2015-01-01

    No organism lives in a constant environment. Based on classical studies in molecular biology, many have viewed microbes as following strict rules for shifting their metabolic activities when prevailing conditions change. For example, students learn that the bacterium Escherichia coli makes proteins for digesting lactose only when lactose is available and glucose, a better sugar, is not. However, recent studies, including three PLOS Biology papers examining sugar utilization in the budding yeast Saccharomyces cerevisiae, show that considerable heterogeneity in response to complex environments exists within and between populations. These results join similar recent results in other organisms that suggest that microbial populations anticipate predictable environmental changes and hedge their bets against unpredictable ones. The classical view therefore represents but one special case in a range of evolutionary adaptations to environmental changes that all organisms face. PMID:25688600

  20. U. S. VETERINARY IMMUNE REAGENTS NETWORK: PROGRESS WITH POULTRY IMMUNE REAGENTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This poster will present a progress report on the CSREES-funded NRI grant to support a broad community approach to systematically address the immunological reagent gap for the US veterinary immunology research community including for the following groups: ruminants (concentrating on cattle but inclu...

  1. Electrodialytic reagent introduction in flow systems.

    PubMed

    Mishra, Santosh K; Dasgupta, Purnendu K

    2010-05-15

    We report on electrodialytic introduction of ionizable molecules of significant size (e.g., 4-(2-pyridyl(azo) resorcinol, PAR)) in capillary scale flow systems. Such reagent introduction can be conducted without volumetric dilution, easily programmed through current control and with excellent mixing characteristics. Electrodialytic transport of large hydrophobic aromatic ions through conventional aromatic ion exchangers is inefficient. Such ions are strongly retained by hydrophobic and pi-pi interactions. An external electric field cannot modulate this retention. We show that the electrodialytic introduction of aromatic dye anions is readily possible through both unmodified cellulose dialysis membranes and through cellulose membranes modified with methacrylate skeleton anion exchangers. The applied electrodialysis current conveniently controls the reagent flux. Although the applied voltage is sufficient to cause electrolytic production of hydrogen and oxygen; the gases are generated outside the flowstream of interest. The present device was constructed with a sub-microliter internal volume. We show capillary scale trace analysis of transition metals. A limit of detection of 0.5 fmol Zn (S/N = 3) is demonstrated with a capillary scale flow injection system with a simple light emitting diode based detector. PMID:20423104

  2. Isotope Shifts

    NASA Astrophysics Data System (ADS)

    Zamick, Larry

    2010-11-01

    A three parameter formula (3P) for isotope shifts r^2(n)= n C +n)n-1)/2A+[n/2]B is related to he staggering parameter G= 2 [r^2(n+1)-r^2(n)]/[r^(n+2)-r^2(n)] If A+B=0 then G=1 (no staggering). If A=0 there is no n dependence to the staggering.One can get G to almost be plus or minus infinity for certain n,but this does not necessarily mean that there are major changes in the nuclear structure. We consider Potassium and Argon isotopes. We also consider quadrupole and monopole core polarization with a delta interaction. We vary the oscillator length parameter of the valence particle but keep the core values fixed. We find for both modes the amount of core polarization decreases as we increase the radius of the valence particle relative to that of the core (for small deviations from the case where the core and valence length parameters are the same).

  3. Liquid-Phase Oxidation of Organic Reagents in Inorganic Analysis

    Microsoft Academic Search

    V. P. Zhivopistsev; A. S. Aramelev

    2001-01-01

    It was shown that the sensitivity of analytical procedures using organic reagents can be significantly increased if a poorly soluble complex of an element with an analytical reagent is oxidized to the products of complete oxidation of organic compounds (CO2?, H2O, and NH3or N2for nitrogen-containing reagents). Knowing the amount of the consumed oxidant, one can easily determine the amount of

  4. Allylic Functionalization of Unactivated Olefins with Grignard Reagents

    PubMed Central

    Bao, Hongli; Bayeh, Liela; Tambar, Uttam K.

    2014-01-01

    Allylic functionalization of unactivated olefins with carbon nucleophiles is a powerful strategy for converting olefins into complex products. We report a general method for functionalizing olefins with aromatic, aliphatic, and vinyl Grignard reagents. In a one-pot process, olefins are oxidized by a commercially available reagent to allylic electrophiles, which undergo selective Cu-catalyzed allylic alkylation with Grignard reagents. Products are formed in high yield and regioselectivity. PMID:24458538

  5. Inactivation of MS2 coliphage by Fenton's reagent

    Microsoft Academic Search

    Jee Yeon Kim; Changha Lee; David L. Sedlak; Jeyong Yoon; Kara L. Nelson

    2010-01-01

    Fenton's reagent (i.e., Fe[II]\\/H2O2) is known to generate strong oxidants capable of oxidizing a broad spectrum of organic compounds in aqueous solution. This study demonstrates the successful inactivation of MS2 coliphage (MS2) by the oxidants produced from Fenton's reagent. The inactivation process of MS2 by Fenton's reagent was found to proceed in two distinct stages. The first stage inactivation, which

  6. New quinolone-based thiol-reactive lanthanide luminescent probes

    PubMed Central

    Wirpsza, Laura; Krasnoperov, Lev; Mustaev, Arkady

    2013-01-01

    Luminescent lanthanide ion complexes are distinguished by unique light emitting properties that enable both highly sensitive detection of lanthanide labels attached to biomolecules and contrast imaging of various micro objects (cells, nanoparticles, etc.). Previously, we synthesized amine-reactive cs124-based luminescent lanthanide chelates with improved brightness and metal retention. Here we report the synthesis of new thiol-reactive derivatives of the same compounds including bromoacetamido-, and maleimido- forms of cs124 and cs124CF3 fluorophores. Maleimido-compounds displayed exceptional reactivity instantaneously coupling to thiols at physiological conditions at micromolar probes concentrations. Surprisingly, they displayed strong quenching by adjacent maleimido-group, which was completely eliminated after reaction with thiols, thereby enabling their simple detection by monitoring the light emission of the reaction mixture. This reaction can be used for hyper-sensitive determination of biologically important sulphydryl compounds (e.g. glutathione, co-enzyme A, etc.) in time-resolved mode. PMID:23833545

  7. Mixed lanthanide oxide nanoparticles as dual imaging agent in biomedicine

    PubMed Central

    Xu, Wenlong; Bony, Badrul Alam; Kim, Cho Rong; Baeck, Jong Su; Chang, Yongmin; Bae, Ji Eun; Chae, Kwon Seok; Kim, Tae Jeong; Lee, Gang Ho

    2013-01-01

    There is no doubt that the molecular imaging is an extremely important technique in diagnosing diseases. Dual imaging is emerging as a step forward in molecular imaging technique because it can provide us with more information useful for diagnosing diseases than single imaging. Therefore, diverse dual imaging modalities should be developed. Molecular imaging generally relies on imaging agents. Mixed lanthanide oxide nanoparticles could be valuable materials for dual magnetic resonance imaging (MRI)-fluorescent imaging (FI) because they have both excellent and diverse magnetic and fluorescent properties useful for dual MRI-FI, depending on lanthanide ions used. Since they are mixed nanoparticles, they are compact, robust, and stable, which is extremely useful for biomedical applications. They can be also easily synthesized with facile composition control. In this study, we explored three systems of ultrasmall mixed lanthanide (Dy/Eu, Ho/Eu, and Ho/Tb) oxide nanoparticles to demonstrate their usefulness as dual T2 MRI–FI agents. PMID:24220641

  8. Ultrasensitive DNAzyme beacon for lanthanides and metal speciation.

    PubMed

    Huang, Po-Jung Jimmy; Lin, Jenny; Cao, Jing; Vazin, Mahsa; Liu, Juewen

    2014-02-01

    Metal-ion detection and speciation analysis is crucial for environmental monitoring. Despite the importance of lanthanides, few sensors are available for their detection. DNAzymes have been previously used to detect divalent metals, while no analytical work was carried out for trivalent and tetravalent ions. Herein, in vitro selection was performed using a Ce(4+) salt as the target metal, and a new DNAzyme (named Ce13) with a bulged hairpin structure was isolated and characterized. Interestingly, Ce13 has almost no activity with Ce(4+) but is highly active with all trivalent lanthanides and Y(3+), serving as a general probe for rare earth metals (omitting Sc). A DNAzyme beacon was engineered detecting down to 1.7 nM Ce(3+) (240 parts per trillion), and other lanthanides showed similar sensitivity. The feasibility of metal speciation analysis was demonstrated by measuring the reduction of Ce(4+) to Ce(3+). PMID:24383540

  9. Enhancing luminescence in lanthanide-doped upconversion nanoparticles.

    PubMed

    Han, Sanyang; Deng, Renren; Xie, Xiaoji; Liu, Xiaogang

    2014-10-27

    The enthusiasm for research on lanthanide-doped upconversion nanoparticles is driven by both a fundamental interest in the optical properties of lanthanides embedded in different host lattices and their promise for broad applications ranging from biological imaging to photodynamic therapy. Despite the considerable progress made in the past decade, the field of upconversion nanoparticles has been hindered by significant experimental challenges associated with low upconversion conversion efficiencies. Recent experimental and theoretical studies on upconversion nanoparticles have, however, led to the development of several effective approaches to enhancing upconversion luminescence, which could have profound implications for a range of applications. Herein we present the underlying principles of controlling energy transfer through lanthanide doping, overview the major advances and key challenging issues in improving upconversion luminescence, and consider the likely directions of future research in the field. PMID:25204638

  10. Plasma mass filtering for separation of actinides from lanthanides

    NASA Astrophysics Data System (ADS)

    Gueroult, R.; Fisch, N. J.

    2014-06-01

    Separating lanthanides from actinides is a key process in reprocessing nuclear spent fuel. Plasma mass filters, which operate on dissociated elements, offer conceptual advantages for such a task as compared with conventional chemical methods. The capabilities of a specific plasma mass filter concept, called the magnetic centrifugal mass filter, are analyzed within this particular context. Numerical simulations indicate separation of americium ions from a mixture of lanthanides ions for plasma densities of the order of 1012 cm-3, and ion temperatures of about 10 eV. In light of collision considerations, separating small fractions of heavy elements from a larger volume of lighter ones is shown to enhance the separation capabilities.

  11. Lattice dynamics of the lanthanides: Samarium at high pressure

    NASA Astrophysics Data System (ADS)

    Olijnyk, H.; Jephcoat, A. P.

    2005-02-01

    Sm was studied by Raman spectroscopy at pressures up to 20 GPa. The Raman-active phonon modes, both of the Sm-type phase and the dhcp phase, show a frequency decrease as pressure increases. There is evidence that the entire structural sequence hcp ? Sm-type ? dhcp ? fcc under pressure for the individual regular lanthanides is associated with softening of certain acoustic and optical-phonon modes as well as elastic anomalies. Comparison is made to corresponding transitions between close-packed lattices in other metals and possible relations to the lanthanide's electronic structure are addressed.

  12. Method for extracting lanthanides and actinides from acid solutions

    DOEpatents

    Horwitz, E. Philip (Naperville, IL); Kalina, Dale G. (Naperville, IL); Kaplan, Louis (Lombard, IL); Mason, George W. (Clarendon Hills, IL)

    1985-01-01

    A process for the recovery of actinide and lanthanide values from aqueous acidic solutions with an organic extractant having the formula: ##STR1## where .phi. is phenyl, R.sup.1 is a straight or branched alkyl or alkoxyalkyl containing from 6 to 12 carbon atoms and R.sup.2 is an alkyl containing from 3 to 6 carbon atoms. The process is suitable for the separation of actinide and lanthanide values from fission product values found together in high level nuclear reprocessing waste solutions.

  13. Method for providing oxygen ion vacancies in lanthanide oxides

    DOEpatents

    Kay, D. Alan R. (4305 Lakeshore Rd., Burlington, CA); Wilson, William G. (820 Harden Dr., Pittsburgh, PA 15229)

    1989-12-05

    A method for desulfurization of fuel gases resulting from the incomplete combustion of sulfur containing hydrocarbons whereby the gases are treated with lanthanide oxides containing large numbers of oxygen-ion vacancies providing ionic porosity which enhances the ability of the lanthanide oxides to react more rapidly and completely with the sulfur in the fuel gases whereby the sulfur in such gases is reduced to low levels suitable for fuels for firing into boilers of power plants generating electricity with steam turbine driven generators, gas turbines, fuel cells and precursors for liquid fuels such as methanol and the like.

  14. The 3-(bromoacetamido)-propylamine hydrochloride: A novel sulfhydryl reagent and its future potential in the configurational study of S1-myosin

    NASA Technical Reports Server (NTRS)

    Sharma, Prasanta; Cheung, Herbert C.

    1989-01-01

    Configurational study of S1-Myosin is an important step towards understanding force generation in muscle contraction. Previously reported NMR studies were corroborated. A new compound was synthesized, 3-(Bromoacetamido)-propylamine hydrochloride. Its potential as a sulfhydryl reagent provides an indirect but elegant approach towards future structural elucidation of S1-Myosin. The preliminary investigation has shown that this compound, BAAP, reacted with S1 in the absence of MgADP. The modified enzyme had a 2-fold increase in CaATPase activity and no detectable K-EDTA ATPase activity. Reaction of BAAP with S1 in the presence of MgADP resulted in a modified enzyme which retained a Ca-ATPase activity that was about 60 percent of the unmodified S1 and had essentially zero K-EDTA ATPase activity. Sulfhydryl titration indicated that about 1.5 and 3.5 SH groups per S1 molecule were blocked by BAAP in the absence and presence of MgADP, respectively. When coupled to a carboxyl group of EDTA, the resulting reagent could become a useful SH reagent in which chelated paramagnetic or luminescent lanthanide ions can be exploited to probe S1 conformation.

  15. Prussian Blue as a Prebiotic Reagent

    NASA Astrophysics Data System (ADS)

    Ruiz-Bermejo, M.; Menor-Salván, C.; Osuna-Esteban, S.; Veintemillas-Verdaguer, S.

    2009-12-01

    Ferrocyanide has been proposed as a potential prebiotic reagent and the complex salt Prussian Blue, Fe4[Fe(CN)6]3, might be an important reservoir of HCN, in the early Earth. HCN is considered the main precursor of amino acids and purine and pyrimidine bases under prebiotic conditions. Recently, we observed the formation of Prussian Blue in spark discharge experiments using saline solutions of ferrous chloride, FeCl2. Using Prussian Blue as starting material in ammonium suspensions, we obtained organic compounds containing nitrogen. These results seem to indicate that Prussian Blue could have been first, a sink of HCN, and then in subsequent reactions, triggered by pH fluctuations, it might have lead to organic life precursors.

  16. Using lanthanide ions to align troponin complexes in solution: Order of lanthanide occupancy in cardiac troponin C

    PubMed Central

    Gay, Grant L.; Lindhout, Darrin A.; Sykes, Brian D.

    2004-01-01

    The potential for using paramagnetic lanthanide ions to partially align troponin C in solution as a tool for the structure determination of bound troponin I peptides has been investigated. A prerequisite for these studies is an understanding of the order of lanthanide ion occupancy in the metal binding sites of the protein. Two-dimensional {1H, 15N} HSQC NMR spectroscopy has been used to examine the binding order of Ce3+, Tb3+, and Yb3+ to both apo- and holo-forms of human cardiac troponin C (cTnC) and of Ce3+ to holo-chicken skeletal troponin C (sTnC). The disappearance of cross-peak resonances in the HSQC spectrum was used to determine the order of occupation of the binding sites in both cTnC and sTnC by each lanthanide. For the lanthanides tested, the binding order follows that of the net charge of the binding site residues from most to least negative; the N-domain calcium binding sites are the first to be filled followed by the C-domain sites. Given this binding order for lanthanide ions, it was demonstrated that it is possible to create a cTnC species with one lanthanide in the N-domain site and two Ca2+ ions in the C-domain binding sites. By using the species cTnC•Yb3+•2 Ca2+ it was possible to confer partial alignment on a bound human cardiac troponin I (cTnI) peptide. Residual dipolar couplings (RDCs) were measured for the resonances in the bound 15N-labeled cTnI129–148 by using two-dimensional {1H, 15N} inphase antiphase (IPAP) NMR spectroscopy. PMID:14978304

  17. Using lanthanide ions to align troponin complexes in solution: order of lanthanide occupancy in cardiac troponin C.

    PubMed

    Gay, Grant L; Lindhout, Darrin A; Sykes, Brian D

    2004-03-01

    The potential for using paramagnetic lanthanide ions to partially align troponin C in solution as a tool for the structure determination of bound troponin I peptides has been investigated. A prerequisite for these studies is an understanding of the order of lanthanide ion occupancy in the metal binding sites of the protein. Two-dimensional [(1)H, (15)N] HSQC NMR spectroscopy has been used to examine the binding order of Ce(3+), Tb(3+), and Yb(3+) to both apo- and holo-forms of human cardiac troponin C (cTnC) and of Ce(3+) to holo-chicken skeletal troponin C (sTnC). The disappearance of cross-peak resonances in the HSQC spectrum was used to determine the order of occupation of the binding sites in both cTnC and sTnC by each lanthanide. For the lanthanides tested, the binding order follows that of the net charge of the binding site residues from most to least negative; the N-domain calcium binding sites are the first to be filled followed by the C-domain sites. Given this binding order for lanthanide ions, it was demonstrated that it is possible to create a cTnC species with one lanthanide in the N-domain site and two Ca(2+) ions in the C-domain binding sites. By using the species cTnC.Yb(3+).2 Ca(2+) it was possible to confer partial alignment on a bound human cardiac troponin I (cTnI) peptide. Residual dipolar couplings (RDCs) were measured for the resonances in the bound (15)N-labeled cTnI(129-148) by using two-dimensional [(1)H, (15)N] inphase antiphase (IPAP) NMR spectroscopy. PMID:14978304

  18. Design of resolving reagents: p-substituted mandelic acids as resolving reagents for 1-arylalkylamines

    Microsoft Academic Search

    Kazushi Kinbara; Kenichi Sakai; Yukihiko Hashimoto; Hiroyuki Nohira; Kazuhiko Saigo

    1996-01-01

    The resolution of 1-arylalkylamines 2–10 by mandelic acid 1 was studied. It was found that a substituent, which elongated the molecular length of the amines, diminished the resolution efficiency. On the basis of these results, (S)-p-methylmandelic acid (S)-11 and (R)-p-methoxymandelic acid (R)-12 were selected as new resolving reagents for the 1-arylalkylamines; these acids were found to have a higher resolving

  19. THE U.S. VETERINARY IMMUNE REAGENTS NETWORK

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As stated at USDA http://www.csrees.usda.gov, “a major obstacle to advances in veterinary immunology and disease control is the lack of sufficient immunological reagents specific for ruminants, swine, poultry, equine and aquaculture species”. Sets of reagents, i.e., monoclonal (mAb) and polyclonal a...

  20. Redox mediation and hydrogen-generation with bipyridinium reagents

    DOEpatents

    Wrighton, Mark S. (Winchester, MA); Bookbinder, Dana C. (East Greenwich, RI); Bruce, James A. (Somerville, MA); Dominey, Raymond N. (Pensacola, FL); Lewis, Nathan S. (Palo Alto, CA)

    1984-03-27

    A variety of redox mediating agents employing bipyridinium reagents and such reagents in conjunction with dispersed noble metals, such as platinium, are disclosed as coatings for substrates and electrodes. The agents may be charged by an applied voltage or by photoelectric effects or may be equilibrated with hydrogen. The agents are useful in reducing biological materials and electrolytic hydrogen production.

  1. EFFECT OF FENTON'S REAGENT ON SUBSURFACE MICROBIOLOGY AND BIODEGRADATION CAPACITY

    EPA Science Inventory

    Microcosm studies were conducted to determine the effect of Fenton's reagent on subsurface microbiology and biodegradation capacity in a DNAPL (PCE/TCE) contaminated aquifer previously treated with the reagent. Groundwater pH declined from 5 to 2.4 immediately after the treatmen...

  2. Polyaminocarboxylic acids as potential candidates for trivalent actinide/lanthanide separations

    NASA Astrophysics Data System (ADS)

    Kissel, Daniel S.

    Nuclear energy, which has historically been considered an alternative energy solution in the United States, is regaining support as an efficient means of energy production. The viability of nuclear energy for the future, however, will remain suspect until issues involving the waste created are fully addressed in the next generation of advanced nuclear fuel cycles. The TALSPEAK process, developed at Oak Ridge National Laboratory, is a classic solvent extraction technique that employs a series of analytical separations in an effort to remove radioactive contaminants from spent nuclear fuel (SNF) and recover uranium in high purity. This separation utilizes a polyaminocarboxylic acid and a phosphorous extractant to separate trivalent actinides (An(III)s) from trivalent lanthanides (Ln(III)s). Conversely, issues with these reagents have hampered TALSPEAK's implementation as an industrial scale solution. The process requires a high concentration of lactic acid to facilitate phase separations, and the An(III)/Ln(III) separation factor is too low to achieve the purity required for artificial transmutation. Artificial transmutation involves steady neutron irradiation, which is impossible in the presence of Ln(III)s because of large neutron capture cross-sections. It is therefore critical to develop superior solvent extractants that effectively separate An(III)s from Ln(III)s. The present study focuses on the design, synthesis, characterization and analysis of advanced polyaminocarboxylic acids and their metal complexes in an effort to identify potential TALSPEAK-type extractants with superior separation properties. A facile, higher yield synthesis of these ligands and their complexation of trivalent metal ions (Co(III), Al(III), Ga(III), and In(III)), and selected lanthanides are reported. The polyaminocarboxylic acids and their trivalent metal complexes were characterized by elemental analysis, mass spectrometry, IR spectroscopy and NMR spectroscopy. Quantum mechanical calculations were performed to obtain the relative stabilities of the three possible geometric isomers for pseudo-octahedral polyaminocarboxylate metal complexes in solution. The calculations were supported by X-ray crystallographic data obtained for different Co(III) and Ga(III) polyaminocarboxylate complexes. Advanced 2D NOESY and classic 1D NMR spectroscopy were used to differentiate experimentally between cis- (C1 symmetry) and both trans- (C2 symmetry) isomers. IR spectroscopy was used to investigate the nature of carboxylate binding for metal complexes isolated in the solid state.

  3. Recovery of lanthanides from Abu Tartur phosphate rock, Egypt

    Microsoft Academic Search

    Monir M Aly; Nabawia A Mohammed

    1999-01-01

    In the present work, a process for the treatment of Abu Tartur phosphate rock for the recovery of lanthanides without interfering with the normal route proposed for fertilizer production, is proposed using HNO3 as a leaching agent. Further, an attempt was made to defluorinate the leach solution in order to upgrade the fertilizer and, at the same time, recover the

  4. Lanthanide template synthesis of a molecular trefoil knot.

    PubMed

    Ayme, Jean-François; Gil-Ramírez, Guzmán; Leigh, David A; Lemonnier, Jean-François; Markevicius, Augustinas; Muryn, Christopher A; Zhang, Gen

    2014-09-24

    We report on a complex featuring three 2,6-pyridinedicarboxamide ligands entwined around a lanthanide (Ln(3+)) ion. The ligand strands can be cyclized by ring-closing olefin metathesis to form a molecular trefoil knot in 58% yield. Demetalation with tetraethylammonium fluoride quantitatively generates the wholly organic 81-atom-loop trefoil knot. PMID:25198065

  5. Spotlights on Recent JACS Publications FLUORESCENT LANTHANIDES TRIGGERED BY

    E-print Network

    Leigh, David A.

    a lanthanide complex bound to a precursor of the light-absorbing molecule coumarin, and a caging, or masking, group prevents the precursor from forming the coumarin structure. This masking group is selected so that it will be unmasked in the presence of the desired analyte; the analyte causes the precursor to react to form coumarin

  6. Detection of Bacterial Spores with Lanthanide-Macrocycle Binary Complexes

    PubMed Central

    Cable, Morgan L.; Kirby, James P.; Levine, Dana J.; Manary, Micah J.; Gray, Harry B.; Ponce, Adrian

    2009-01-01

    The detection of bacterial spores via dipicolinate-triggered lanthanide luminescence has been improved in terms of detection limit, stability, and susceptibility to interferents by use of lanthanide-macrocycle binary complexes. Specifically, we compared the effectiveness of Sm, Eu, Tb and Dy complexes with the macrocycle 1,4,7,10-tetraazacyclododecane-1,7-diacetate (DO2A) to the corresponding lanthanide aquo ions. The Ln(DO2A)+ binary complexes bind dipicolinic acid (DPA), a major constituent of bacterial spores, with greater affinity and demonstrate significant improvement in bacterial spore detection. Of the four luminescent lanthanides studied, the terbium complex exhibits the greatest dipicolinate binding affinity (100-fold greater than Tb3+ alone, and 10-fold greater than other Ln(DO2A)+ complexes) and highest quantum yield. Moreover, the inclusion of DO2A extends the pH range over which Tb-DPA coordination is stable, reduces the interference of calcium ions nearly 5-fold, and mitigates phosphate interference 1000-fold compared to free terbium alone. In addition, detection of Bacillus atrophaeus bacterial spores was improved by the use of Tb(DO2A)+, yielding a 3-fold increase in the signal-to-noise ratio over Tb3+. Out of the eight cases investigated, the Tb(DO2A)+ binary complex is best for the detection of bacterial spores. PMID:19537757

  7. On the suitability of lanthanides as actinide analogs

    SciTech Connect

    Raymond, Kenneth; Szigethy, Geza [Chemistry Department, University of California, Berkeley, CA, 94720-1460 (United States)

    2008-07-01

    With the current level of actinide materials used in civilian power generation and the need for safe and efficient methods for the chemical separation of these species from their daughter products and for long-term storage requirements, a detailed understanding of actinide chemistry is of great importance. Due to the unique bonding properties of the f-elements, the lanthanides are commonly used as structural and chemical models for the actinides, but differences in the bonding between these 4f and 5f elements has become a question of immediate applicability to separations technology. This brief overview of actinide coordination chemistry in the Raymond group at UC Berkeley/LBNL examines the validity of using lanthanide analogs as structural models for the actinides, with particular attention paid to single crystal X-ray diffraction structures. Although lanthanides are commonly accepted as reasonable analogs for the actinides, these comparisons suggest the careful study of actinide materials independent of their lanthanide analogs to be of utmost importance to present and future efforts in nuclear industries. (authors)

  8. Enhancement of Anion Binding in Lanthanide Optical Sensors

    PubMed Central

    Cable, Morgan L.; Kirby, James P.; Gray, Harry B.; Ponce, Adrian

    2013-01-01

    In the design of molecular sensors, researchers exploit binding interactions that are usually defined in terms of topology and charge complementarity. The formation of complementary arrays of highly cooperative, noncovalent bonding networks facilitates protein-ligand binding, leading to motifs such as the ‘lock-and-key.’ Synthetic molecular sensors often employ metal complexes as key design elements as a way to construct a binding site with the desired shape and charge to achieve target selectivity. In transition metal complexes, coordination number, structure and ligand dynamics are governed primarily by a combination of inner-sphere covalent and outer-sphere noncovalent interactions. These interactions provide a rich variable space that researchers can use to tune structure, stability and dynamics. In contrast, lanthanide(III)-ligand complex formation and ligand-exchange dynamics are dominated by reversible electrostatic and steric interactions, because the unfilled f shell is shielded by the larger, filled d shell. Luminescent lanthanides such as terbium, europium, dysprosium and samarium display many photophysical properties that make them excellent candidates for molecular sensor applications. Complexes of lanthanide ions act as receptors that exhibit a detectable change in metal-based luminescence upon binding of an anion. In our work on sensors for detection of dipicolinate, the unique biomarker of bacterial spores, we discovered that the incorporation of an ancillary ligand (AL) can enhance binding constants of target anions to lanthanide ions by as much as two orders of magnitude. In this Account, we show that selected ALs in lanthanide/anion systems greatly improve sensor performance for medical, planetary science and biodefense applications. We suggest that the observed anion binding enhancement could result from an AL-induced increase in positive charge at the lanthanide ion binding site. This effect depends on lanthanide polarizability, which can be established from the ionization energy of Ln3+ ? Ln4+. These results account for the order Tb3+ > Dy3+ > Eu3+ ? Sm3+. As with many lanthanide properties, ranging from hydration enthalpy to vaporization energy, this AL-induced enhancement shows a large discrepancy between Tb3+ and Eu3+ despite their similarity in size, a phenomenon known as the ‘gadolinium break.’ This discrepancy, based on the unusual stabilities of the Eu2+ and Tb4+ oxidation states, results from the half-shell effect, as both of these ions have half-filled 4f-shells. The high polarizability of Tb3+ explains the extraordinarily large increase in the binding affinity of anions for terbium compared to other lanthanides. We recommend that researchers consider this AL-induced enhancement when designing lanthanide-macrocycle optical sensors. Ancillary ligands also can reduce the impact of interfering species such as phosphate) commonly found in environmental and physiological samples. PMID:24032446

  9. Enhancement of anion binding in lanthanide optical sensors.

    PubMed

    Cable, Morgan L; Kirby, James P; Gray, Harry B; Ponce, Adrian

    2013-11-19

    In the design of molecular sensors, researchers exploit binding interactions that are usually defined in terms of topology and charge complementarity. The formation of complementary arrays of highly cooperative, noncovalent bonding networks facilitates protein-ligand binding, leading to motifs such as the "lock-and-key". Synthetic molecular sensors often employ metal complexes as key design elements as a way to construct a binding site with the desired shape and charge to achieve target selectivity. In transition metal complexes, coordination number, structure and ligand dynamics are governed primarily by a combination of inner-sphere covalent and outer-sphere noncovalent interactions. These interactions provide a rich variable space that researchers can use to tune structure, stability, and dynamics. In contrast, lanthanide(III)-ligand complex formation and ligand-exchange dynamics are dominated by reversible electrostatic and steric interactions, because the unfilled f shell is shielded by the larger, filled d shell. Luminescent lanthanides such as terbium, europium, dysprosium, and samarium display many photophysical properties that make them excellent candidates for molecular sensor applications. Complexes of lanthanide ions act as receptors that exhibit a detectable change in metal-based luminescence upon binding of an anion. In our work on sensors for detection of dipicolinate, the unique biomarker of bacterial spores, we discovered that the incorporation of an ancillary ligand (AL) can enhance binding constants of target anions to lanthanide ions by as much as two orders of magnitude. In this Account, we show that selected ALs in lanthanide/anion systems greatly improve sensor performance for medical, planetary science, and biodefense applications. We suggest that the observed anion binding enhancement could result from an AL-induced increase in positive charge at the lanthanide ion binding site. This effect depends on lanthanide polarizability, which can be established from the ionization energy of Ln(3+) ? Ln(4+). These results account for the order Tb(3+) > Dy(3+) > Eu(3+) ? Sm(3+). As with many lanthanide properties, ranging from hydration enthalpy to vaporization energy, this AL-induced enhancement shows a large discrepancy between Tb(3+) and Eu(3+) despite their similarity in size, a phenomenon known as the "gadolinium break". This discrepancy, based on the unusual stabilities of the Eu(2+) and Tb(4+) oxidation states, results from the half-shell effect, as both of these ions have half-filled 4f-shells. The high polarizability of Tb(3+) explains the extraordinarily large increase in the binding affinity of anions for terbium compared to other lanthanides. We recommend that researchers consider this AL-induced enhancement when designing lanthanide-macrocycle optical sensors. Ancillary ligands also can reduce the impact of interfering species such as phosphate commonly found in environmental and physiological samples. PMID:24032446

  10. Lanthanide sorption on smectitic clays in presence of cement leachates

    NASA Astrophysics Data System (ADS)

    Galunin, Evgeny; Alba, María D.; Santos, Maria J.; Abrão, Taufik; Vidal, Miquel

    2010-02-01

    Due to their potential retention capacity, clay minerals have been proposed for use in the engineered barriers for the storage of high-level radioactive actinides in deep geological waste repositories. However, there is still a lack of data on the sorption of actinides in clays in conditions simulating those of the repositories. The present article examines the sorption of two lanthanides (actinide analogues) in a set of smectitic clays (FEBEX bentonite, MX80 bentonite, hectorite, saponite, Otay montmorillonite, and Texas montmorillonite). Distribution coefficients ( Kd) were determined in two media: water and 0.02 mol L -1 Ca, the latter representing the cement leachates that may modify the chemical composition of the water in contact with the clay. The Kd values of the lanthanides used in the experiments (La and Lu) varied greatly (25-50 000 L kg -1) depending on the ionic medium (higher values in water than in the Ca medium), the initial lanthanide concentration (up to three orders of magnitude decrease inversely with lanthanide concentration), and the examined clay (up to one order of magnitude for the same lanthanide and sorption medium). Freundlich and Langmuir isotherms were used to fit sorption data to allow comparison of the sorption parameters among smectites. The model based on the two-site Langmuir isotherms provided the best fit of the sorption data, confirming the existence of sorption sites with different binding energies. The sites with higher sorption affinity were about 6% of the total sorption capacity in the water medium, and up to 17% in the Ca medium, although in this latter site sorption selectivity was lower. The wide range of Kd values obtained regarding the factors examined indicated that the retention properties of the clays should also be considered when selecting a suitable clay for engineered barriers.

  11. Spectroscopic studies on the lanthanide sensitized luminescence and chemiluminescence properties of fluoroquinolone with different structure

    NASA Astrophysics Data System (ADS)

    Sun, Chunyan; Ping, Hong; Zhang, Minwei; Li, Hongkun; Guan, Fengrui

    2011-11-01

    Lanthanide sensitized luminescence and chemiluminescence (CL) are of great importance because of the unique spectral properties, such as long lifetime, large Stokes shifts, and narrow emission bands characteristic to lanthanide ions (Ln 3+). With the fluoroquinolone (FQ) compounds including enoxacin (ENX), norfloxacin (NFLX), lomefloxacin (LMFX), fleroxacin (FLRX), ofloxacin (OFLX), rufloxacin (RFX), gatifloxacin (GFLX) and sparfloxacin (SPFX), the luminescence and CL properties of Tb 3+-FQ and Eu 3+-FQ complexes have been investigated in this contribution. Ce 4+-SO 32- in acidic conditions was taken as the CL system and sensitized CL intensities of Tb 3+-FQ and Eu 3+-FQ complexes were determined by flow-injection analysis. The luminescence and CL spectra of Tb 3+-FQ complexes show characteristic peaks of Tb 3+ at 490 nm, 545 nm, 585 nm and 620 nm. Complexes of Tb 3+-ENX, Tb 3+-NFLX, Tb 3+-LMFX and Tb 3+-FLRX display relatively strong emission intensity compared with Tb 3+-OFLX, Tb 3+-RFX, Tb 3+-GFLX and Tb 3+-SPFX. Quite weak peaks with unique characters of Eu 3+ at 590 nm and 617 nm appear in the luminescence and CL spectra of Eu 3+-ENX, but no notable sensitized luminescence and CL of Eu 3+ could be observed when Eu 3+ is added into other FQ. The distinct differences on emission intensity of Tb 3+-FQ and Eu 3+-FQ might originate from the different energy gap between the triplet levels of FQ and the excited levels of the Ln 3+. The different sensitized luminescence and CL signals among Tb 3+-FQ complexes could be attributed to different optical properties and substituents of these FQ compounds. The detailed mechanism involved in the luminescence and CL properties of Tb 3+-FQ and Eu 3+-FQ complexes has been investigated by analyzing the luminescence and CL spectra, quantum yields, and theoretical calculation results.

  12. Feasibility of the electrochemical way in molten fluorides for separating thorium and lanthanides and extracting lanthanides from the solvent

    NASA Astrophysics Data System (ADS)

    Chamelot, P.; Massot, L.; Hamel, C.; Nourry, C.; Taxil, P.

    2007-01-01

    An alternative way of reprocessing nuclear fuel by hydrometallurgy could be using treatment with molten salts, particularly fluoride melts. Moreover, one of the six concepts chosen for GEN IV nuclear reactors (Technology Roadmap - http://gif.inel.gov/roadmap/) is the molten salt reactor (MSR). The originality of the concept is the use of molten salts as liquid fuel and coolant. During the running of the reactor, fission products, particularly lanthanides, accumulate in the melt and have to be eliminated to optimise reactor operation. This study concerns the feasibility of the separation actinides-lanthanides-solvent by selectively electrodepositing the elements to be separated on an inert (Mo, Ta) or a reactive (Ni) cathodic substrate in molten fluoride media. The main results of this work lead to the conclusions that: The solvents to be used for efficient separation must be fluoride media containing lithium as cation. Inert substrates are suitable for actinide/lanthanide separation; nickel substrate is more suitable for the extraction of lanthanides from the solvent, owing to the depolarisation occurring in the cathodic process through alloy formation.

  13. Hypervalent Iodine Reagents Very Important Paper DOI: 10.1002/anie.201310897

    E-print Network

    Müller, Peter

    Hypervalent Iodine Reagents Very Important Paper DOI: 10.1002/anie.201310897 Structural Reevaluation of the Electrophilic Hypervalent Iodine Reagent for Trifluoromethylthiolation Supported* Abstract: Hypervalent iodine l3 -benziodoxoles are common electrophilic transfer reagents known

  14. Chiral Shift Reagent Analysis of Enantioselectivity in Baker's Yeast Reductions of Ethylacetoacetate.

    ERIC Educational Resources Information Center

    Lipkowitz, K. B.; Mooney, J. L.

    1987-01-01

    Described is a laboratory exercise that uses nuclear magnetic resonance to monitor enantiomeric excess in asymmetric reductions. The laboratory exercise has been used successfully with undergraduate organic chemistry students. (RH)

  15. Synthesis, Characterization, and Use of a Cobalt(II) Complex as an NMR Shift Reagent.

    ERIC Educational Resources Information Center

    Goff, Harold M.; And Others

    1982-01-01

    Describes procedures for preparing acetylacetonate complex of cobalt(II), followed by spectrophotometric analysis to characterize the material, with additional characterization methods supplied by students to provide open-ended dimension for the experiment. (SK)

  16. Isoquinoline-based lanthanide complexes: bright NIR optical probes and efficient MRI agents.

    PubMed

    Caillé, Fabien; Bonnet, Célia S; Buron, Frédéric; Villette, Sandrine; Helm, Lothar; Petoud, Stéphane; Suzenet, Franck; Tóth, Eva

    2012-02-20

    In the objective of developing ligands that simultaneously satisfy the requirements for MRI contrast agents and near-infrared emitting optical probes that are suitable for imaging, three isoquinoline-based polyaminocarboxylate ligands, L1, L2 and L3, have been synthesized and the corresponding Gd(3+), Nd(3+) and Yb(3+) complexes investigated. The specific challenge of the present work was to create NIR emitting agents which (i) have excitation wavelengths compatible with biological applications and (ii) are able to emit a sufficient number of photons to ensure sensitive NIR detection for microscopic imaging. Here we report the first observation of a NIR signal arising from a Ln(3+) complex in aqueous solution in a microscopy setup. The lanthanide complexes have high thermodynamic stability (log K(LnL) =17.7-18.7) and good selectivity for lanthanide ions versus the endogenous cations Zn(2+), Cu(2+), and Ca(2+) thus preventing transmetalation. A variable temperature and pressure (17)O NMR study combined with nuclear magnetic relaxation dispersion measurements yielded the microscopic parameters characterizing water exchange and rotation. Bishydration of the lanthanide cation in the complexes, an important advantage to obtain high relaxivity for the Gd(3+) chelates, has been demonstrated by (17)O chemical shifts for the Gd(3+) complexes and by luminescence lifetime measurements for the Yb(3+) analogues. The water exchange on the three Gd(3+) complexes is considerably faster (k(ex)(298) = (13.9-15.4) × 10(6) s(-1)) than on commercial Gd(3+)-based contrast agents and proceeds via a dissociative mechanism, as evidenced by the large positive activation volumes for GdL1 and GdL2 (+10.3 ± 0.9 and +10.6 ± 0.9 cm(3) mol(-1), respectively). The relaxivity of GdL1 is doubled at 40 MHz and 298 K in fetal bovine serum (r(1) = 16.1 vs 8.5 mM(-1) s(-1) in HEPES buffer), due to hydrophobic interactions between the chelate and serum proteins. The isoquinoline core allows for the optimization of the optical properties of the luminescent lanthanide complexes in comparison to the pyridinic analogues and provides significant shifts of the excitation energies toward lower values which therefore become more adapted for biological applications. L2 and L3 bear two methoxy substituents on the aromatic core in ortho and para positions, respectively, that further modulate their electronic structure. The Nd(3+) and Yb(3+) complexes of the ligand L3, which incorporates the p-dimethoxyisoquinoline moiety, can be excited up to 420 nm. This wavelength is shifted over 100 nm toward lower energy in comparison to the pyridine-based analogue. The luminescence quantum yields of the Nd(3+) (0.013-0.016%) and Yb(3+) chelates (0.028-0.040%) are in the range of the best nonhydrated complexes, despite the presence of two inner sphere water molecules. More importantly, the 980 nm NIR emission band of YbL3 was detected with a good sensitivity in a proof of concept microscopy experiment at a concentration of 10 ?M in fetal bovine serum. Our results demonstrate that even bishydrated NIR lanthanide complexes can emit a sufficient number of photons to ensure sensitive detection in practical applications. In particular, these ligands containing an aromatic core with coordinating pyridine nitrogen can be easily modified to tune the optical properties of the NIR luminescent lanthanide complexes while retaining good complex stability and MRI characteristics for the Gd(3+) analogues. They constitute a highly versatile platform for the development of bimodal MR and optical imaging probes based on a simple mixture of Gd(3+) and Yb(3+)/Nd(3+) complexes using an identical chelator. Given the presence of two inner sphere water molecules, important for MRI applications of the corresponding Gd(3+) analogues, this result is particularly exciting and opens wide perspectives not only for NIR imaging based on Ln(3+) ions but also for the design of combined NIR optical and MRI probes. PMID:22233349

  17. Toward mechanistic understanding of nuclear reprocessing chemistries by quantifying lanthanide solvent extraction kinetics via microfluidics with constant interfacial area and rapid mixing.

    PubMed

    Nichols, Kevin P; Pompano, Rebecca R; Li, Liang; Gelis, Artem V; Ismagilov, Rustem F

    2011-10-01

    The closing of the nuclear fuel cycle is an unsolved problem of great importance. Separating radionuclides produced in a nuclear reactor is useful both for the storage of nuclear waste and for recycling of nuclear fuel. These separations can be performed by designing appropriate chelation chemistries and liquid-liquid extraction schemes, such as in the TALSPEAK process (Trivalent Actinide-Lanthanide Separation by Phosphorus reagent Extraction from Aqueous Komplexes). However, there are no approved methods for the industrial scale reprocessing of civilian nuclear fuel in the United States. One bottleneck in the design of next-generation solvent extraction-based nuclear fuel reprocessing schemes is a lack of interfacial mass transfer rate constants obtained under well-controlled conditions for lanthanide and actinide ligand complexes; such rate constants are a prerequisite for mechanistic understanding of the extraction chemistries involved and are of great assistance in the design of new chemistries. In addition, rate constants obtained under conditions of known interfacial area have immediate, practical utility in models required for the scaling-up of laboratory-scale demonstrations to industrial-scale solutions. Existing experimental techniques for determining these rate constants suffer from two key drawbacks: either slow mixing or unknown interfacial area. The volume of waste produced by traditional methods is an additional, practical concern in experiments involving radioactive elements, both from disposal cost and experimenter safety standpoints. In this paper, we test a plug-based microfluidic system that uses flowing plugs (droplets) in microfluidic channels to determine absolute interfacial mass transfer rate constants under conditions of both rapid mixing and controlled interfacial area. We utilize this system to determine, for the first time, the rate constants for interfacial transfer of all lanthanides, minus promethium, plus yttrium, under TALSPEAK process conditions, as a first step toward testing the molecular mechanism of this separation process. PMID:21888347

  18. Oxidation of hydroxymethanesulfonic acid by Fenton's reagent

    NASA Astrophysics Data System (ADS)

    Martin, L. R.; Easton, M. P.; Foster, J. W.; Hill, M. W.

    We have studied the oxidation of hydroxymethanesulfonic acid (HSMA) in Fenton's reagent (hydrogen peroxide and ferrous ion), and we have used a relative rate method to estimate the absolute rate constant for oxidation of HSMA by OH radicals. We conclude that the atmospheric oxidation of HMSA by OH is slow if Fenton's-type reactions are the only source of OH, but other sources of OH may be present. Fenton's reaction in the absence of other reactants is a weak source of OH radicals at atmospheric concentrations of hydrogen peroxide and iron. On the other hand, the estimate of the absolute reaction rate, based on the rate relative to the oxidation of pinacol by OH, is 1.25 ±0.25 × 10 9M-1s-1. This rate implies that HMSA can be oxidized fairly rapidly by OH in atmospheric aerosols, based on present models for the OH concentration in atmospheric aerosols. We also measured the rate of decomposition of HMSA and the acetaldehyde-bisulfite complex, HESA. The rate of decomposition of HESA at pH 2 is 300 times faster than that of HMSA, and on this basis we believe that HESA would not be very effective at protecting sulfur (IV) from oxidation in the atmosphere.

  19. Immunomicrospheres - Reagents for cell labeling and separation

    NASA Technical Reports Server (NTRS)

    Rembaum, A.; Dreyer, W. J.

    1980-01-01

    Immunomicrospheres are specially designed microscopic particles that have antibodies or similar molecules chemically bound to their surfaces. The antibody-coated microspheres react in a highly specific way with target cells, viruses, or other antigenic agents. Immunomicrospheres may be synthesized so that they incorporate compounds that are highly radioactive, intensely fluorescent, magnetic, electron opaque, highly colored, or pharmacologically active. These various types of microspheres may be coated with pure, highly specific monoclonal antibodies obtained by the new hybridoma cell cloning techniques or with conventional antibody preparations. Some of the many present and potential applications for these new reagents are (1) new types of radioimmune or immunofluorescent assays, (2) improved fluorescence microscopy, (3) separation of cells on the basis of the fluorescent, electrophoretic, or magnetic properties of bound immunomicrospheres, (4) markers for use in several types of electron or standard light microscopy, and (5) delivery of lethal compouds to specific undesirable living cells. The combination of the various new types of synthetic microspheres and the newly available homogeneous antibodies offers new opportunities in research, diagnosis, and therapy.

  20. Reactivity of chemiluminescence reagents toward oxidants

    SciTech Connect

    Khevelev, M.; Weinstein-Loyd, J.B. [State Univ. of New York, Old Westbury, NY (United States)

    1996-10-01

    Hydroperoxyl radical (HO{sub 2}) and its conjugate base, superoxide radical (O{sub 2}{sup -}) are important chemical intermediates. O{sub 2}{sup -} is ubiquitous in aerobic cells and has been implicated in arthritis, cancer, and aging, among other biological processes. HO{sub 2} plays a central role in atmospheric photochemistry. Because of their short lifetime, there are few reliable analytical methods for the detection of HO{sub 2}/O{sub 2}{sup -}. In a number of recent publications, the chemiluminescence reagent CLA has been exploited as a specific marker for these species. Using UV/visible spectroscopy, we have investigated the stability of CLA and several of its analogs in the presence of oxidants, including O{sub 2}, H{sub 2}O{sub 2}, OH and HO{sub 2}/O{sub 2}{sup -}. The spectral changes observed suggest that the reaction with HO{sub 2}/O{sub 2}{sup -} is rather nonspecific.

  1. Arithmetic shift operators

    Microsoft Academic Search

    Stuart Sutherland

    \\u000a Verilog-1995 provides two simple shift operators: The >> token represents a bitwise shift-right operation. The << token represents\\u000a a bitwise shift-left operation. Both shift operators will shift the bits in the first operand the number of times indicated\\u000a by the value in the second operand. The bits which are vacated by the shift are always zero filled.

  2. [Production of a new monoclonal anti-AB reagent].

    PubMed

    Habti, N; Tissent, A; Benchemsi, N

    2003-09-01

    Techniques of monoclonal antibodies production have well progressed in the developed countries. But, they are still absent in the third world. In this report, the murine hybridoma technology was performed to produce anti-ABH monoclonal antibodies. The anti-AB specificity of several hybridomas was determined by agglutination techniques using phenotyped red cells panels. An anti-AB monoclonal antibody was selected and compared to other reagents for its use as a blood grouping reagent. Its characteristics were in accordance with the international standards. Hybridoma establishment to produce a good monoclonal reagent is henceforth possible in Morocco. PMID:14563419

  3. Hypersensitivity pneumonitis in a technician using Pauli's reagent.

    PubMed Central

    Evans, W V; Seaton, A

    1979-01-01

    A technician working in a medical laboratory used a spray of sodium diazobenzenesulphate (Pauli's reagent) in chromatography. She developed a respiratory illness with both airways obstruction and radiographic and physiological evidence of interstitial pneumonitis. An occupational type of challenge test was followed by both immediate and late bronchial obstructive responses, by a fall in arterial oxygen tension, and by increased radiographic shadowing. Histology of a lung biopsy specimen, a low serum C3, and a postive skin prick test to the reagent suggested that the illness was a hypersensitivity reaction to Pauli's reagent. Images PMID:542917

  4. Comparison of amino acid derivatization reagents for LC-ESI-MS analysis. Introducing a novel phosphazene-based derivatization reagent.

    PubMed

    Rebane, Riin; Oldekop, Maarja-Liisa; Herodes, Koit

    2012-09-01

    Amino acid analysis with high performance liquid chromatography with electrospray ionization mass spectrometry (LC-ESI-MS) is an emerging method. For more sensitive analysis, derivatization is used and next to commercially available derivatization reagents such as dansyl chloride (DNS), 9-fluorenylmethyl chloroformate (FMOC-Cl) and diethyl ethoxymethylenemalonate (DEEMM), new derivatization reagents are designed specially for LC-ESI-MS, like p-N,N,N-trimethylammonioanilyl N'-hydroxysuccinimidyl carbamate iodide (TAHS) which provides very low limits of detection. In this work, a novel phosphazene based derivatization reagent (FOSF) that provides comparable limits of quantitation (LoQ) to TAHS is introduced. Moreover, a thorough comparison between FOSF, TAHS, DNS, FMOC-Cl and DEEMM is carried out for 7 different amino acids - Arg, Asp, Gly, ?-Ala, Pro, Trp and Phe. This is a first time that thorough comparison is carried out on the same instrument for amino acid derivatization reagents. Results on the same instrument for five amino acid derivatization reagents show that novel reagents are sensitive with LoQ values around 80 fmol but have disadvantages such as problematic chromatographic separation. Next to novel reagents, DEEMM offers very good LoQ-s (average of 150 fmol) and wide dynamic linear range. PMID:22889992

  5. Effects of a novel cell stabilizing reagent on DNA amplification by PCR as compared to traditional stabilizing reagents.

    PubMed

    Das, Kausik; Fernando, M Rohan; Basiaga, Sara; Wigginton, Stephanie M; Williams, Tom

    2014-01-01

    Stabilization of nucleated blood cells by cell stabilizing reagent (BCT reagent) present in the Cell-Free DNA BCT blood collection device and consequent prevention of cell-free DNA contamination by cellular DNA during sample storage and shipping have previously been reported. This study was conducted to investigate the effect of this novel cell stabilizing reagent on DNA amplification by PCR as compared to traditional cell stabilizing reagents, formaldehyde and glutaraldehyde. A 787 bp long DNA fragment from human glyceraldehydes-3-phosphate dehydrogenase (GAPDH) gene was amplified by PCR and used as model system. DNA samples and blood samples were treated with BCT reagent, 0.1% formaldehyde or 0.1% glutaraldehyde at room temperature. DNA amplification was studied using conventional and real-time quantitative PCR. Results indicate that exposure of DNA to the BCT reagent for up to 14 days had no effect on DNA amplification by PCR as compared to the untreated control DNA. However, there was statistically significant decrease in DNA amplification in the DNA samples treated with formaldehyde and glutaraldehyde. We conclude that the BCT reagent used in Cell-Free DNA BCT blood collection device to prevent cell-free DNA contamination by cellular DNA had no effect on DNA amplification by PCR. PMID:23810682

  6. Lanthanide-containing polycations for monitoring polyplex dynamics via lanthanide resonance energy transfer.

    PubMed

    Kelkar, Sneha S; Xue, Lian; Turner, S Richard; Reineke, Theresa M

    2014-05-12

    Theranostic nanomaterials have emerged in the past decade that combine therapeutic delivery and diagnostic imaging into one package. Such materials offer the opportunity to aid diagnosis, track therapeutic biodistribution, and monitor drug release. We have developed a series of nucleic acid delivery polymers containing oligoethylene amines that are able to be protonated at physiological pH (for binding/compacting pDNA) and a lanthanide-chelating domain, which imparts diagnostic functionality. Diamine monomers (containing between 3 and 6 Boc-protected ethyleneamines) were prepared via a multistep procedure involving the selective protection and deprotection of primary and secondary amines. The polymer structures were then synthesized by step-growth polymerization of the oligoethylene diamines with a bisanhydride of diethylenetriamine pentaacetic acid (DTPA-BA), yielding degrees of polymerization between 18 and 24. Chelation of the polymers with gadolinium and terbium was performed to offer MRI contrast agent and luminescence properties, respectively. All of the polymer chelates were found to house approximately one water coordination site, as calculated by the Horrock's equation and possess longitudinal relaxivities (r1, on a per Gd basis) at least twice that of Magnevist, a clinical contrast agent. All the structures formed polyplexes with pDNA with highly positive zeta potentials and hydrodynamic diameters around 50-80 nm. Lanthanide resonance energy transfer (LRET) was used to monitor polyplex association and dissociation. Polyplexes were formed using the donor-acceptor pair comprising of terbium-chelated polymer with five ethyleneamines within the repeat unit (6c-Tb) and tetramethyl rhodamine (TMR)-labeled pDNA. Association/dissociation in the presence of heparin and NaCl was monitored. The effect of amine number along the polymer backbone on transfection efficiency and cytotoxicity was also investigated. None of the polymers revealed cytotoxic effects with cultured cells; however, the polymer with six ethyleneamines clearly offered the highest transfection efficiency. This preliminary study offers insight into the development of materials with the ability to monitor polyplex unpackaging over time within the cellular environment. PMID:24611467

  7. Dynamic tests for actinide/lanthanide separation by CMPO solvent in fluorinated diluents

    SciTech Connect

    Tkachenko, L.; Babain, V.; Alyapyshev, M.; Vizniy, A.; Il'in, A. [V. G. Khlopin Radium Institute, 2nd Murinskiy Ave 28., St. Petersburg 194021 (Russian Federation); Shadrin, A. [A.A. Bochvar High-technology Research Institute of Inorganic Materials, 5-a, Rogova str., Moscow 123098 (Russian Federation)

    2013-07-01

    Actinide and lanthanide extraction by new solvent: 0.2 M phenyl-octyl-N,N-diiso-butylcarbamoyl-phosphine oxide (CMPO) + 30% TBP + formal of octafluoro-pentanol was studied. A dynamic test with this solvent was performed. It was shown that americium and lanthanides are effectively extracted from PUREX process raffinate. The separation of americium from light lanthanides was confirmed in the modified SETFICS flowsheet with this new solvent. (authors)

  8. Spectroscopic properties and luminescence enhancement of lanthanide mixed complexes Ln? 3L in zirconia glasses

    Microsoft Academic Search

    R. Reisfeld; J. Legendziewicz; M. Puchalska; T. Saraidarov

    2004-01-01

    The search for new compounds sensitizing lanthanides emission is of growing interest. Lanthanide mixed chelates of the type Ln?3L (L-Lewis base; 2,2?-bipyridine, 1.10-phenanthroline) seem to be promising in this area. In this work the new types of the lanthanide mixed chelates with phosphoro-azo-derivatives of ?-diketonates and 2,2?-bipyridine were incorporated in zirconia glasses by the sol–gel techniques. The thin zirconia films

  9. Praseodymium Nitrate and Neodymium Complexation with Organophosphorus Reagents in Supercritical Carbon Dioxide Solvent

    SciTech Connect

    Robert V. Fox; R. Duane Ball; Peter de B. Harrington; Harry W. Rollins; John G. Jolley; Chien M. Wai

    2004-11-01

    Complex formation reactions of praseodymium nitrate hexahydrate, and neodymium nitrate hexahydrate salts with tri-n-butyl phosphate (TBP) and several other neutral organophosphorus reagents were investigated in supercritical carbon dioxide. The concentration of the metal complexes in the supercritical fluid (SCF) phase was determined using UV-Vis and luminescence spectroscopies. The stoichiometry of the complexes was determined using the mole-ratio method. Extraction equilibrium constants were calculated from the spectral data using least-squares regression and hard-equilibria models. UV-Vis absorbance data indicate that praseodymium nitrate and neodymium nitrate both form 1:4 lanthanide–tributyl phosphate complexes in supercritical carbon dioxide at 308 K. The conditional extraction coefficients for those two systems were calculated to be log Kex=7.45±0.06 for the praseodymium system and log Kex=7.52±0.03 for the neodymium system. For comparison, neodymium nitrate complexation reactions with tri-n-butyl phosphate and tributyl phosphite (TBPO3) were studied in hexane under ambient conditions. UV-Vis data indicate that a 1:4 neodymium–tributyl phosphate complex is formed in hexane with a conditional extraction coefficient of log Kex=3.4±0.2. Tributyl phosphite forms a 1:8 complex with neodymium in hexane with a conditional extraction coefficient of log Kex=11.0±0.1. Neodymium nitrate was titrated with other organophosphorus reagents, tributyl phosphite and tributyl phosphine oxide (TBPO), in supercritical carbon dioxide to investigate differences between neutral oxygen donor ligands and neutral phosphorus donor ligands. UV-Vis and luminescence data indicate that neodymium nitrate forms a 1:8 complex with tributyl phosphite and a 1:5 complex with tributyl phosphine oxide, compared to a 1:4 complex with tri-n-butyl phosphate. The conditional extraction coefficient for the 1:8 neodymium–tributyl phosphite system was calculated as log Kex=21.4±0.2 from UV-Vis data, and log Kex=19.8±0.2 from luminescence data. The conditional extraction coefficient for the 1:5 neodymium–tributyl phosphine oxide complex was calculated as log Kex=7.83±0.05.

  10. Polymeric Microspheres as Protein Transduction Reagents*

    PubMed Central

    Nagel, David; Behrendt, Jonathan M.; Chimonides, Gwen F.; Torr, Elizabeth E.; Devitt, Andrew; Sutherland, Andrew J.; Hine, Anna V.

    2014-01-01

    Discovering the function of an unknown protein, particularly one with neither structural nor functional correlates, is a daunting task. Interaction analyses determine binding partners, whereas DNA transfection, either transient or stable, leads to intracellular expression, though not necessarily at physiologically relevant levels. In theory, direct intracellular protein delivery (protein transduction) provides a conceptually simpler alternative, but in practice the approach is problematic. Domains such as HIV TAT protein are valuable, but their effectiveness is protein specific. Similarly, the delivery of intact proteins via endocytic pathways (e.g. using liposomes) is problematic for functional analysis because of the potential for protein degradation in the endosomes/lysosomes. Consequently, recent reports that microspheres can deliver bio-cargoes into cells via a non-endocytic, energy-independent pathway offer an exciting and promising alternative for in vitro delivery of functional protein. In order for such promise to be fully exploited, microspheres are required that (i) are stably linked to proteins, (ii) can deliver those proteins with good efficiency, (iii) release functional protein once inside the cells, and (iv) permit concomitant tracking. Herein, we report the application of microspheres to successfully address all of these criteria simultaneously, for the first time. After cellular uptake, protein release was autocatalyzed by the reducing cytoplasmic environment. Outside of cells, the covalent microsphere–protein linkage was stable for ?90 h at 37 °C. Using conservative methods of estimation, 74.3% ± 5.6% of cells were shown to take up these microspheres after 24 h of incubation, with the whole process of delivery and intracellular protein release occurring within 36 h. Intended for in vitro functional protein research, this approach will enable study of the consequences of protein delivery at physiologically relevant levels, without recourse to nucleic acids, and offers a useful alternative to commercial protein transfection reagents such as Chariot™. We also provide clear immunostaining evidence to resolve residual controversy surrounding FACS-based assessment of microsphere uptake. PMID:24692642

  11. The lanthanides and yttrium in minerals of the apatite group; a review

    USGS Publications Warehouse

    Fleischer, Michael; Altschuler, Z.S.

    1982-01-01

    More than 1000 analyses have been tabulated of the distribution of the lanthanides and yttrium in minerals of the apatite group, recalculated to atomic percentages. Average compositions have been calculated for apatites from 14 types of rocks. These show a progressive change of composition from apatites of granitic pegmatites, highest in the heavy lanthanides and yttrium, to those from alkalic pegmatites, highest in the light lanthanides and lowest in yttrium. This progression is clearly shown in plots of S (= at % La+Ce+Pr) vs the ratio La/Nd and of S vs the ratio 100Y/(Y+Ln), where Ln is the sum of the lanthanides. Apatites of sedimentary phosphorites occupy a special position, being relatively depleted in Ce and relatively enriched in yttrium and the heavy lanthanides, consequences of deposition from sea water. Apatites associated with iron ores are close in composition to apatites of carbonatites, alkalic ultramafic, and ultramafic rocks, being enriched in the light lanthanides and depleted in the heavy lanthanides. Their compositions do not support the hypothesis of Parak that the Kiruna-type ores are of sedimentary origin. Table 9 and Figures 1-3 show the dependence of lanthanide distribution on the nature of the host rock. Although a given analysis of the lanthanides does not unequivocally permit certain identification of the host rock, it can indicate a choice of highly probable host rocks.

  12. 21 CFR 866.3035 - Arizona spp. serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...serological reagents. 866.3035 Section 866.3035 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...microorganisms. Arizona spp. can cause gastroenteritis (food poisoning) and sepsis (blood poisoning). (b)...

  13. 21 CFR 866.3630 - Serratia spp. serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...serological reagents. 866.3630 Section 866.3630 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...are occasionally associated with gastroenteritis (food poisoning) and wound infections. (b)...

  14. 21 CFR 866.3035 - Arizona spp. serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...serological reagents. 866.3035 Section 866.3035 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...microorganisms. Arizona spp. can cause gastroenteritis (food poisoning) and sepsis (blood poisoning). (b)...

  15. 21 CFR 866.3630 - Serratia spp. serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...serological reagents. 866.3630 Section 866.3630 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...are occasionally associated with gastroenteritis (food poisoning) and wound infections. (b)...

  16. 21 CFR 866.3630 - Serratia spp. serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...serological reagents. 866.3630 Section 866.3630 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...are occasionally associated with gastroenteritis (food poisoning) and wound infections. (b)...

  17. 21 CFR 866.3035 - Arizona spp. serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...serological reagents. 866.3035 Section 866.3035 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...microorganisms. Arizona spp. can cause gastroenteritis (food poisoning) and sepsis (blood poisoning). (b)...

  18. 21 CFR 866.3035 - Arizona spp. serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...serological reagents. 866.3035 Section 866.3035 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...microorganisms. Arizona spp. can cause gastroenteritis (food poisoning) and sepsis (blood poisoning). (b)...

  19. 21 CFR 864.4020 - Analyte specific reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Identification. Analyte specific reagents (ASR's) are antibodies, both polyclonal and monoclonal, specific receptor...Manufacture and Clinical Evaluation of In Vitro Tests to Detect Antibodies to the Human Immunodeficiency Virus, Type I” (54 FR...

  20. Generation, structure and reactivity of tertiary organolithium reagents.

    PubMed

    Perry, Matthew A; Rychnovsky, Scott D

    2015-03-25

    Covering: up to 2014Tertiary alkyllithium reagents are very useful intermediates in synthesis. Alkyllithium reagents with adjacent heteroatoms may be formed stereoselectively or may react stereoselectively, and have been used in the synthesis of alkaloids, C-glycosides and spirocycles. An overview of the generation, reactivity and stereochemistry of tertiary alkyllithium reagents will be presented, as well as examples of their use in organic synthesis. The discussion will be focused on a conceptual understanding of the generation and reactivity of these intermediates. The reactions described herein generate fully substituted carbon atoms, and the forces driving stereoselectivity will be discussed in detail. Where appropriate, computational results will be introduced to provide a better understanding for the structure and reactivity of tertiary alkyllithium reagents. PMID:25475042

  1. 21 CFR 866.3240 - Equine encephalomyelitis virus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3240 Section 866.3240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  2. 21 CFR 866.3850 - Trichinella spiralis serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3850 Section 866.3850 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  3. 21 CFR 866.3145 - Coxsackievirus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3145 Section 866.3145 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  4. 21 CFR 866.3490 - Rhinovirus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3490 Section 866.3490 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  5. 21 CFR 866.3035 - Arizona spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3035 Section 866.3035 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  6. 21 CFR 866.3360 - Lymphocytic choriomeningitis virus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3360 Section 866.3360 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  7. 21 CFR 866.3700 - Staphylococcus aureus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3700 Section 866.3700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  8. 21 CFR 866.3405 - Poliovirus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3405 Section 866.3405 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  9. 21 CFR 866.3510 - Rubella virus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3510 Section 866.3510 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  10. 21 CFR 866.3460 - Rabiesvirus immuno-fluorescent reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3460 Section 866.3460 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  11. 21 CFR 866.3660 - Shigella spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3660 Section 866.3660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  12. 21 CFR 866.3135 - Coccidioides immitis serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3135 Section 866.3135 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  13. 21 CFR 866.3340 - Klebsiella spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3340 Section 866.3340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  14. 21 CFR 866.3120 - Chlamydia serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3120 Section 866.3120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  15. 21 CFR 866.3205 - Echovirus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3205 Section 866.3205 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  16. 21 CFR 866.3415 - Pseudomonas spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3415 Section 866.3415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  17. 21 CFR 866.3330 - Influenza virus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3330 Section 866.3330 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  18. 21 CFR 866.3040 - Aspergillus spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3040 Section 866.3040 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  19. 21 CFR 866.3630 - Serratia spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3630 Section 866.3630 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  20. 21 CFR 866.3370 - Mycobacterium tuberculosis immunofluorescent reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3370 Section 866.3370 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  1. 21 CFR 866.3400 - Parainfluenza virus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3400 Section 866.3400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  2. 21 CFR 866.3220 - Entamoeba histolytica serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3220 Section 866.3220 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  3. 21 CFR 866.3350 - Leptospira spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3350 Section 866.3350 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  4. 21 CFR 866.3520 - Rubeola (measles) virus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3520 Section 866.3520 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  5. 21 CFR 866.3060 - Blastomyces dermatitidis serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3060 Section 866.3060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  6. 21 CFR 866.3140 - Corynebacterium spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    21 Food and Drugs 8 2010-04-01 2010-04-01... 866.3140 Section 866.3140 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents §...

  7. Lithium Reagents DOI: 10.1002/anie.200603038

    E-print Network

    Collum, David B.

    Lithium Reagents DOI: 10.1002/anie.200603038 Lithium Diisopropylamide: Solution Kinetics Keywords: kinetics · lithium diisopropylamide · metalation · solvent effects · synthesis design D. B: lithium diiso- propylamide (LDA). LDA has played a profound role in organic synthesis, serving as the base

  8. Characterizing fluidic seals for on-board reagent delivery

    NASA Astrophysics Data System (ADS)

    Inamdar, Tejas; Anthony, Brian W.

    2013-03-01

    The reagent delivery mechanism in a point-of-care, HIV diagnostic, microfluidic device is studied. Reagents held in an aluminum blister pack are released on the opening of a fluidic seal. The fluidic seals, controlling the flow of reagents, are characterized to reduce anomalies in the desired flow pattern. The findings of this research can be divided into three categories - 1) bonding phenomenon 2) influence of seal pattern on flow and rupture mechanics and 3) process parameters which minimize flow anomalies. Four seal patterns - line hemisphere, line flat, chevron hemisphere and chevron flat were created and tested for reagent delivery using a flow sensor and a force gauge. Experiments suggest that one of the patterns - line-flat - inducted the fewest flow anomalies. A parameter scoping exercise of the seal manufacturing process parameters (temperature, time, pressure) was performed for the line flat seal. Temperature, time, pressure / gap and distance settings which minimize flow anomalies were found.

  9. 21 CFR 864.4020 - Analyte specific reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...and monoclonal, specific receptor proteins, ligands, nucleic acid sequences, and similar reagents which, through...February 28, 1994. 4. “Draft Review Criteria for Nucleic Acid Amplification-Based In Vitro Diagnostic Devices...

  10. 21 CFR 864.4020 - Analyte specific reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...and monoclonal, specific receptor proteins, ligands, nucleic acid sequences, and similar reagents which, through...February 28, 1994. 4. “Draft Review Criteria for Nucleic Acid Amplification-Based In Vitro Diagnostic Devices...

  11. 21 CFR 864.4020 - Analyte specific reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...and monoclonal, specific receptor proteins, ligands, nucleic acid sequences, and similar reagents which, through...February 28, 1994. 4. “Draft Review Criteria for Nucleic Acid Amplification-Based In Vitro Diagnostic Devices...

  12. 21 CFR 864.4020 - Analyte specific reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...and monoclonal, specific receptor proteins, ligands, nucleic acid sequences, and similar reagents which, through...February 28, 1994. 4. “Draft Review Criteria for Nucleic Acid Amplification-Based In Vitro Diagnostic Devices...

  13. Oxidation of p-hydroxybenzoic acid by Fenton's reagent

    Microsoft Academic Search

    Francisco J. Rivas; Fernando J. Beltrán; Jesús Frades; Paco Buxeda

    2001-01-01

    Fenton's reagent has been shown to be a feasible technique to treat phenolic-type compounds present in a variety of food processing industry wastewaters. A model compound, p-hydroxybenzoic acid was oxidised by continuously pumping two solutions of ferrous iron and hydrogen peroxide. Typical operating variables like reagent feeding concentrations and flowrate, temperature and pH were studied. A mechanism of reactions based

  14. Gel-forming reagents and uses thereof for preparing microarrays

    DOEpatents

    Golova, Julia (Burr Ridge, IL); Chernov, Boris (Burr Ridge, IL); Perov, Alexander (Woodridge, IL)

    2010-11-09

    New gel-forming reagents including monomers and cross-linkers, which can be applied to gel-drop microarray manufacturing by using co-polymerization approaches are disclosed. Compositions for the preparation of co-polymerization mixtures with new gel-forming monomers and cross-linker reagents are described herein. New co-polymerization compositions and cross-linkers with variable length linker groups between unsaturated C.dbd.C bonds that participate in the formation of gel networks are disclosed.

  15. The first quaternary lanthanide(III) nitride iodides: NaM{sub 4}N{sub 2}I{sub 7} (M=La-Nd)

    SciTech Connect

    Schurz, Christian M. [Institut fuer Anorganische Chemie, Universitaet Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart (Germany); Schleid, Thomas, E-mail: schleid@iac.uni-stuttgart.d [Institut fuer Anorganische Chemie, Universitaet Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart (Germany)

    2010-10-15

    In attempts to synthesize lanthanide(III) nitride iodides with the formula M{sub 2}NI{sub 3} (M=La-Nd), moisture-sensitive single crystals of the first quaternary sodium lanthanide(III) nitride iodides NaM{sub 4}N{sub 2}I{sub 7} (orthorhombic, Pna2{sub 1}; Z=4; a=1391-1401, b=1086-1094, c=1186-1211 pm) could be obtained. The dominating structural features are {sup 1}{sub {infinity}}{l_brace}[NM{sub 4/2}{sup e}]{sup 3+}{r_brace} chains of trans-edge linked [NM{sub 4}]{sup 9+} tetrahedra, which run parallel to the polar 2{sub 1}-axis [001]. Between the chains, direct bonding via special iodide anions generates cages, in which isolated [NaI{sub 6}]{sup 5-} octahedra are embedded. The IR spectrum of NaLa{sub 4}N{sub 2}I{sub 7} recorded from 100 to 1000 cm{sup -1} shows main bands at {upsilon}=337, 373 and 489 cm{sup -1}. With decreasing radii of the lanthanide trications these bands, which can be assigned as an influence of the vibrations of the condensed [NM{sub 4}]{sup 9+} tetrahedra, are shifted toward higher frequencies for the NaM{sub 4}N{sub 2}I{sub 7} series (M=La-Nd), following the lanthanide contraction. - Abstract: View at the main structural features of the NaM{sub 4}N{sub 2}I{sub 7} series (M=La-Nd): The {sup 1}{sub {infinity}}{l_brace}[NM{sub 4/2}{sup e}]{sup 3+}{r_brace} chains, consisting of trans-edge connected [NM{sub 4}]{sup 9+} tetrahedra, and the special kind of iodide anions, namely (I7){sup -}, form cages, in which isolated [NaI{sub 6}]{sup 5-} octahedra are embedded.

  16. Lanthanide complexes of triethylenetetramine tetra-, penta-, and hexaacetamide ligands as paramagnetic chemical exchange-dependent saturation transfer contrast agents for magnetic resonance imaging: nona- versus decadentate coordination.

    PubMed

    Burdinski, Dirk; Pikkemaat, Jeroen A; Lub, Johan; de Peinder, Peter; Nieto Garrido, Lidia; Weyhermüller, Thomas

    2009-07-20

    The solid state and solution structure of a series of lanthanide complexes of the decadentate ligand triethylenetetramine-N,N,N',N'',N''',N'''-hexaacetamide, (ttham), its two decadentate derivatives di-tert-butyl N,N,N''',N'''-tetra(carbamoylmethyl)-triethylenetetramine-N',N''-diacetate (Bu(2)ttha-tm) and N,N,N''',N'''-tetra(carbamoylmethyl)-triethylenetetramine-N',N''-diacetic acid (H(2)ttha-tm), and its two nonadentate derivatives N-benzyl-triethylenetetramine-N,N',N'',N''',N'''-pentaacetamide (1bttpam) and N'-benzyl-triethylenetetramine-N,N,N'',N''',N'''-pentaacetamide (4bttpam) have been investigated by infrared and Raman spectroscopy, X-ray crystallography, cyclovoltammetry, and NMR spectroscopy. In these mononuclear lanthanide complexes, the first coordination sphere is generally saturated by four amine nitrogens of the triethylenetetramine ligand backbone and five or six carbonyl oxygen atoms of the pendent amide or acetate donor groups. In the [Ln(ttham)](3+) complex series, a switch from a decadentate to a nonadentate coordination occurs between [Er(ttham)](3+) and [Tm(ttham)](3+). This switch in coordination mode, which is caused by decreasing metal ion radii going from lanthanum to lutetium (lanthanide contraction), has no significant effect on the T(1)-relaxivity of these complexes. It is shown that the T(1)-relaxivity is dominated by second coordination sphere interactions, with an ascendant contribution of the classical dipolar relaxation mechanism for the earlier (Ce-Sm) and very late (Tm, Yb) lanthanides, and a prevailing Curie relaxation mechanism for most of the remaining paramagnetic lanthanide ions. In chemical exchange-dependent saturation transfer (CEST) (1)H NMR experiments, most of the above complexes exhibit multiple strong CEST peaks of the paramagnetically shifted amide protons spread over a >100 ppm chemical shift range. The effective CEST effect of the studied thulium complexes strongly depends on temperature and pH. The pH at which the CEST effect maximizes (generally between pH 7 and 8) is determined by the overall charge of the complex. Depending on the used saturation frequency offset, the temperature-dependence varies between the extremes of strongly linearly dependent and fully independent in the case of [Tm(ttham)](3+). In combination with the strong pH-dependence of the CEST effect at the latter frequency offset, this complex is highly suitable for simultaneous temperature and pH mapping using magnetic resonance imaging. PMID:19507818

  17. Lanthanides caged by the organic chelates; structural properties

    NASA Astrophysics Data System (ADS)

    Smentek, Lidia

    2011-04-01

    The structure, in particular symmetry, geometry and morphology of organic chelates coordinated with the lanthanide ions are analyzed in the present review. This is the first part of a complete presentation of a theoretical description of the properties of systems, which are widely used in technology, but most of all, in molecular biology and medicine. The discussion is focused on the symmetry and geometry of the cages, since these features play a dominant role in the spectroscopic activity of the lanthanides caged by organic chelates. At the same time, the spectroscopic properties require more formal presentation in the language of Racah algebra, and deserve a separate analysis. In addition to the parent systems of DOTA, DOTP, EDTMP and CDTMP presented here, their modifications by various antennas are analyzed. The conclusions that have a strong impact upon the theory of the energy transfer and the sensitized luminescence of these systems are based on the results of numerical density functional theory calculations.

  18. Photoluminescence and electroluminescence of new lanthanide-(methyoxybenzoyl)benzoate complexes

    NASA Astrophysics Data System (ADS)

    Edwards, A.; Claude, C.; Sokolik, I.; Chu, T. Y.; Okamoto, Y.; Dorsinville, R.

    1997-08-01

    New luminescent thermally stable lanthanide-organic complexes, namely europium tris(4-methoxy benzoylbenzoate), Eu(MeOBB)3, and terbium tris(4-methoxy benzoylbenzoate), Tb(MeOBB)3, were synthesized and characterized. The UV absorption bands in these compounds are attributed to the ligand while the emission originates from the lanthanide ions' electronic transitions. The quantum efficiency of photoluminescence, ?, measured in 5×10-4 M methylene chloride solutions is relatively large in both compounds: ?=0.27 for Tb(MeOBB)3 and ?=0.16 for Eu(MeOBB)3. The narrow-band electroluminescence from these complexes is studied by fabricating and characterizing single- and multi-layer organic light emitting diodes. Energy transfer between the organic components of these devices is also discussed.

  19. A TRUEX-based separation of americium from the lanthanides

    SciTech Connect

    Bruce J. Mincher; Nicholas C. Schmitt; Mary E. Case

    2011-03-01

    Abstract: The inextractability of the actinide AnO2+ ions in the TRUEX process suggests the possibility of a separation of americium from the lanthanides using oxidation to Am(V). The only current method for the direct oxidation of americium to Am(V) in strongly acidic media is with sodium bismuthate. We prepared Am(V) over a wide range of nitric acid concentrations and investigated its solvent extraction behavior for comparison to europium. While a separation is achievable in principal, the presence of macro amounts of cerium competes for the sparingly soluble oxidant and the oxidant itself competes for CMPO complexation. These factors conspire to reduce the Eu/Am separation factor from ~40 using tracer solutions to ~5 for extractions from first cycle raffinate simulant solution. To separate pentavalent americium directly from the lanthanides using the TRUEX process, an alternative oxidizing agent will be necessary.

  20. Practical Synthesis of Cytidine-5-Carboxamide-Modified Nucleotide Reagents

    PubMed Central

    Rohloff, John C.; Fowler, Catherine; Ream, Brian; Carter, Jeffrey D.; Wardle, Greg; Fitzwater, Tim

    2015-01-01

    Chemically-modified derivatives of cytidine, bearing a 5-(N-substituted-carboxamide) functional group, are new reagents for use in aptamer discovery via the SELEX process (Systematic Evolution of Ligands by EXponential enrichment). Herein, we disclose a practical synthesis of 5-(N-benzylcarboxamide)-2?-deoxycytidine, and the corresponding 5-(N-1-naphthylmethylcarboxamide)- and 5-(N-3-phenylpropylcarboxamide)-2?-deoxycytidine analogs, as both the suitably-protected 3?-O-cyanoethylphosphoramidite reagents (CEP; gram scale) and the 5?-O-triphosphate reagents (TPP; milligram-scale). The key step in the syntheses is a mild, palladium(0)-catalyzed carboxyamidation of an unprotected 5-iodo-cytidine. Use of the CEP reagents for solid-phase oligonucleotide synthesis was demonstrated and incorporation of the TPP reagents by KOD polymerase in a primer extension assay confirmed the utility of these reagents for SELEX. Finally, the carboxyamidation reaction was also used to prepare the nuclease-resistant sugar-variants: 5-(N-benzylcarboxamide)-2?-O-methyl-cytidine and 5-(N-3-phenylpropylcarboxamide)-2?-deoxy-2?-fluoro-cytidine. PMID:25710355

  1. Practical synthesis of cytidine-5-carboxamide-modified nucleotide reagents.

    PubMed

    Rohloff, John C; Fowler, Catherine; Ream, Brian; Carter, Jeffrey D; Wardle, Greg; Fitzwater, Tim

    2015-03-01

    Chemically-modified derivatives of cytidine, bearing a 5-(N-substituted-carboxamide) functional group, are new reagents for use in aptamer discovery via the SELEX process (Systematic Evolution of Ligands by EXponential enrichment). Herein, we disclose a practical synthesis of 5-(N-benzylcarboxamide)-2'-deoxycytidine, and the corresponding 5-(N-1-naphthylmethylcarboxamide)- and 5-(N-3-phenylpropylcarboxamide)-2'-deoxycytidine analogs, as both the suitably-protected 3'-O-cyanoethylphosphoramidite reagents (CEP; gram scale) and the 5'-O-triphosphate reagents (TPP; milligram-scale). The key step in the syntheses is a mild, palladium(0)-catalyzed carboxyamidation of an unprotected 5-iodo-cytidine. Use of the CEP reagents for solid-phase oligonucleotide synthesis was demonstrated and incorporation of the TPP reagents by KOD polymerase in a primer extension assay confirmed the utility of these reagents for SELEX. Finally, the carboxyamidation reaction was also used to prepare the nuclease-resistant sugar-variants: 5-(N-benzylcarboxamide)-2'-O-methyl-cytidine and 5-(N-3-phenylpropylcarboxamide)-2'-deoxy-2'-fluoro-cytidine. PMID:25710355

  2. EQUILIBRIUM OF SOLVENT EXTRACTION OF LANTHANIDE IONS WITH DIDODECYLPHOSPHORIC ACID

    Microsoft Academic Search

    Kazuo Kondo; Koji Momota; Funiyuki Nakashio

    1989-01-01

    Measurement of the extraction equilibrium of europium by didodecylphosphoric acid dissolved in toluene diluent vas carried out at 303 K. From vapor-phase osmometry, it was found that the extractant (HR) is apt to diaerize in toluene diluent. It vas clarified that the lanthanide ion (Ln) is extracted according to the following equation.The extraction equilibrium constant of the metal vas obtained.The

  3. Complexes of Alkyl Esters of Ethylidenediphosphonic Acids with Lanthanide Nitrates

    Microsoft Academic Search

    Vladislav Arabadzhiev; Jordanka Petrova; Erhard T. K. Haupt; Jürgen Kopf; Isabelle Nevoigt

    2008-01-01

    The lanthanide complexes LnL2(NO3)33a?c and 5a?c, where Ln is La, Ce and Sm and L are tetraethyl esters of ethylidenediphosphonic acid 1 (for complexes 3) and tetraisopropyl esters of ethylidenediphosphonic acid 4 (for complexes 5) were synthesized and characterized by elemental analysis, IR and NMR spectroscopy. The crystal structure of DyL2(NO3)37 (L is tetraisopropyl ester of methylenediphosphonic acid) was determined

  4. Oxidative Injury in the Brain of mice Caused by Lanthanid

    Microsoft Academic Search

    Haiquan Zhao; Zhe Cheng; Renping Hu; Jie Chen; Mengmeng Hong; Min Zhou; Xiaolan Gong; Ling Wang; Fashui Hong

    2011-01-01

    The organ toxicity of lanthanides (Ln) on organisms had been recognized, but very little is known about the oxidative injury\\u000a of brain caused by Ln. In order to study the mechanisms underlying the effects of Ln on the brain, ICR mice were injected\\u000a with a single 20 mg\\/kg body weight dose of LaCl3, CeCl3, and NdCl3 into the abdominal cavity daily

  5. Thermal Decomposition of Lanthanide, Yttrium, and Scandium Oxalates and Carbonates

    NASA Astrophysics Data System (ADS)

    Sharov, Vyacheslav A.; Bezdenezhnykh, G. V.

    1981-07-01

    Data concerning the thermal decomposition of lanthanide, yttrium, and scandium oxalates and carbonates are surveyed. The complexity of the process, the large number of stages involved, and the dependence of the composition of the intermediates in the thermal transformations on the experimental conditions is noted. Certain process characteristics have been discovered and it is concluded that the decomposition process depends on the ionic radius of the metal. The bibliography includes 83 references.

  6. A Revised Periodic Table: With the Lanthanides Repositioned

    Microsoft Academic Search

    Michael Laing

    2005-01-01

    The lanthanide elements from lanthanum to lutetium inclusive are incorporated into the body of the periodic table. They are\\u000a subdivided into three sub-groups according to their important oxidation states: La to Sm, Eu to Tm, Yb and Lu, so that Eu\\u000a and Yb fall directly below Ba; La, Gd, Lu form a column directly below Y; Ce and Tb fall

  7. Characterization and Classification of Lanthanides by Multivariate-Analysis Methods

    NASA Astrophysics Data System (ADS)

    Horovitz, Ossi; Sârbu, Costel

    2005-03-01

    A chemometric study was conducted on a data set consisting of 18 characteristics, mainly physical properties of the 14 lanthanides and lanthanum, including Sc and Y. Classical methods of multivariate analysis, namely, principal component analysis (PCA) and cluster analysis (CA) were applied. The results obtained by using the Statistica software package are presented and discussed concerning the correlations between the properties and those between the elements themselves. The discussion and findings are based on the tables of correlation, the eigenvectors and eigenvalues of PCA, the 2D- and 3D-representations of the loadings of variables and scores of the elements corresponding to the first principal components, including also the dendrograms obtained by using CA. Loadings scatterplots are used as a display tool for examining the relationships between properties, looking for trends, grouping, or outliers. In the same way, the scatterplots of scores emphasized the difference between La and the lanthanides on the one side and Sc and Y on the other and support setting Lu as their homologue, rather than La. On the basis of these findings, a ”periodic system“ of the lanthanides is suggested that agrees well with chemical intuition.

  8. Magnetic Relaxation Mechanisms in Lanthanide Single Molecule Magnets

    NASA Astrophysics Data System (ADS)

    Chibotaru, Liviu; Ungur, Liviu; McInnes, Eric; Winpenny, Richard

    2013-03-01

    Ab initio investigation of multiplet spectrum of lanthanides in archetypal coordination geometries shows an unexpected regular structure consisting of (i) mirror symmetry of anisotropic magnetic properties of doublet states, (ii) high magnetic axiality of low-lying and high-lying doublets, comparable to complexes with ideal axial symmetry, and (iii) the strong rotation of the anisotropy axes of individual doublets [1]. The obtained high axiality of the ground doublet states explains the SMM behaviour of low-symmetry lanthanide complexes. Ab initio calculations predict that depending on the relative orientation of anisotropy axes in different doublet states, the relaxation can proceed via the first or the second excited state. Here we report new lanthanide cage complexes where two competing relaxation pathways through the first and second excited states are observed, leading to very high energy barriers for loss of magnetisation [2]. [1] L. Ungur, L.F. Chibotaru, P.C.C.P., 2011, 13, 20086--20090. [2] R.J. Blagg, L. Ungur, F. Tuna, D. Collison, E.J.L. McInnes L.F. Chibotaru, R.E.P. Winpenny,. Nat. Chem., submitted.

  9. Semiempirical quantum chemistry model for the lanthanides: RM1 (Recife Model 1) parameters for dysprosium, holmium and erbium.

    PubMed

    Filho, Manoel A M; Dutra, José Diogo L; Rocha, Gerd B; Simas, Alfredo M; Freire, Ricardo O

    2014-01-01

    Complexes of dysprosium, holmium, and erbium find many applications as single-molecule magnets, as contrast agents for magnetic resonance imaging, as anti-cancer agents, in optical telecommunications, etc. Therefore, the development of tools that can be proven helpful to complex design is presently an active area of research. In this article, we advance a major improvement to the semiempirical description of lanthanide complexes: the Recife Model 1, RM1, model for the lanthanides, parameterized for the trications of Dy, Ho, and Er. By representing such lanthanide in the RM1 calculation as a three-electron atom with a set of 5 d, 6 s, and 6 p semiempirical orbitals, the accuracy of the previous sparkle models, mainly concentrated on lanthanide-oxygen and lanthanide-nitrogen distances, is extended to other types of bonds in the trication complexes' coordination polyhedra, such as lanthanide-carbon, lanthanide-chlorine, etc. This is even more important as, for example, lanthanide-carbon atom distances in the coordination polyhedra of the complexes comprise about 30% of all distances for all complexes of Dy, Ho, and Er considered. Our results indicate that the average unsigned mean error for the lanthanide-carbon distances dropped from an average of 0.30 Å, for the sparkle models, to 0.04 Å for the RM1 model for the lanthanides; for a total of 509 such distances for the set of all Dy, Ho, and Er complexes considered. A similar behavior took place for the other distances as well, such as lanthanide-chlorine, lanthanide-bromine, lanthanide, phosphorus and lanthanide-sulfur. Thus, the RM1 model for the lanthanides, being advanced in this article, broadens the range of application of semiempirical models to lanthanide complexes by including comprehensively many other types of bonds not adequately described by the previous models. PMID:24497945

  10. Semiempirical Quantum Chemistry Model for the Lanthanides: RM1 (Recife Model 1) Parameters for Dysprosium, Holmium and Erbium

    PubMed Central

    Filho, Manoel A. M.; Dutra, José Diogo L.; Rocha, Gerd B.; Simas, Alfredo M.; Freire, Ricardo O.

    2014-01-01

    Complexes of dysprosium, holmium, and erbium find many applications as single-molecule magnets, as contrast agents for magnetic resonance imaging, as anti-cancer agents, in optical telecommunications, etc. Therefore, the development of tools that can be proven helpful to complex design is presently an active area of research. In this article, we advance a major improvement to the semiempirical description of lanthanide complexes: the Recife Model 1, RM1, model for the lanthanides, parameterized for the trications of Dy, Ho, and Er. By representing such lanthanide in the RM1 calculation as a three-electron atom with a set of 5 d, 6 s, and 6 p semiempirical orbitals, the accuracy of the previous sparkle models, mainly concentrated on lanthanide-oxygen and lanthanide-nitrogen distances, is extended to other types of bonds in the trication complexes’ coordination polyhedra, such as lanthanide-carbon, lanthanide-chlorine, etc. This is even more important as, for example, lanthanide-carbon atom distances in the coordination polyhedra of the complexes comprise about 30% of all distances for all complexes of Dy, Ho, and Er considered. Our results indicate that the average unsigned mean error for the lanthanide-carbon distances dropped from an average of 0.30 Å, for the sparkle models, to 0.04 Å for the RM1 model for the lanthanides; for a total of 509 such distances for the set of all Dy, Ho, and Er complexes considered. A similar behavior took place for the other distances as well, such as lanthanide-chlorine, lanthanide-bromine, lanthanide, phosphorus and lanthanide-sulfur. Thus, the RM1 model for the lanthanides, being advanced in this article, broadens the range of application of semiempirical models to lanthanide complexes by including comprehensively many other types of bonds not adequately described by the previous models. PMID:24497945

  11. Preparation and luminescence properties of lanthanide (Eu3+, Sm3+) complexes and their hectorite-based composites.

    PubMed

    Ma, Jun; Jia, Yongzhong; Jing, Yan; Sun, Jinhe; Yao, Ying; Wang, Xiaohua

    2010-02-01

    The complexes of europium and samarium with phthalates ligands were synthesized and characterized. The luminescence behaviors of the lanthanide complexes as well as their hectorite-based composites were investigated by fluorescence spectra. The results indicated that the lanthanide complexes showed slightly lower intensities in hectorite matrix than that of corresponding pure complexes. The lanthanide ion relative fluorescence intensity (LRFI) was enhanced when the lanthanide complexes were doped into hectorite. PMID:20036189

  12. Preparation and luminescence properties of lanthanide (Eu 3+, Sm 3+) complexes and their hectorite-based composites

    NASA Astrophysics Data System (ADS)

    Ma, Jun; Jia, Yongzhong; Jing, Yan; Sun, Jinhe; Yao, Ying; Wang, Xiaohua

    2010-02-01

    The complexes of europium and samarium with phthalates ligands were synthesized and characterized. The luminescence behaviors of the lanthanide complexes as well as their hectorite-based composites were investigated by fluorescence spectra. The results indicated that the lanthanide complexes showed slightly lower intensities in hectorite matrix than that of corresponding pure complexes. The lanthanide ion relative fluorescence intensity (LRFI) was enhanced when the lanthanide complexes were doped into hectorite.

  13. Selective removal of lanthanides from natural waters, acidic streams and dialysate

    PubMed Central

    Yantasee, Wassana; Fryxell, Glen E.; Addleman, R. Shane; Wiacek, Robert J.; Koonsiripaiboon, View; Pattamakomsan, Kanda; Sukwarotwat, Vichaya; Xu, Jide; Raymond, Kenneth N.

    2009-01-01

    The increased demand for the lanthanides in commercial products result in increased production of lanthanide containing ores, which increases public exposure to the lanthanides, both from various commercial products and from production wastes/effluents. This work investigates lanthanide (La, Ce, Pr, Nd, Eu, Gd and Lu) binding properties of self-assembled monolayers on mesoporous silica supports (SAMMS™), that were functionalized with diphosphonic acid (DiPhos), acetamide phosphonic acid (AcPhos), propionamide phosphonic acid (Prop-Phos), and 1-hydroxy-2-pyridinone (1,2-HOPO), from natural waters (river, ground and sea waters), acid solutions (to mimic certain industrial process streams), and dialysate. The affinity, capacity, and kinetics of the lanthanide sorption, as well as regenerability of SAMMS materials were investigated. Going from the acid side over to the alkaline side, the AcPhos- and DiPhos-SAMMS maintain their outstanding affinity for lanthanides, which enable the use of the materials in the systems where the pH may fluctuate. In acid solutions, Prop-Phos- and 1,2-HOPO-SAMMS have differing affinity along the lanthanide series, suggesting their use in chromatographic lanthanide separation. Over 95% of 100 µg/L of Gd in dialysate was removed by the Prop-Phos-SAMMS after 1 min and 99% over 10 min. SAMMS can be regenerated with an acid wash (0.5 M HCl) without losing the binding properties. Thus, they have a great potential to be used as in large-scale treatment of lanthanides, lanthanide separation prior to analytical instruments, and in sorbent dialyzers for treatment of acute lanthanide poisoning. PMID:19345006

  14. Lanthanide tris(?-diketonates) as useful probes for chirality determination of biological amino alcohols in vibrational circular dichroism: ligand to ligand chirality transfer in lanthanide coordination sphere.

    PubMed

    Miyake, Hiroyuki; Terada, Keiko; Tsukube, Hiroshi

    2014-06-01

    A series of lanthanide tris(?-diketonates) functioned as useful chirality probes in the vibrational circular dichroism (VCD) characterization of biological amino alcohols. Various chiral amino alcohols induced intense VCD signals upon ternary complexation with racemic lanthanide tris(?-diketonates). The VCD signals observed around 1500 cm(-1) (?-diketonate IR absorption region) correlated well with the stereochemistry and enantiomeric purity of the targeted amino alcohol, while the corresponding monoalcohol, monoamine, and diol substrates induced very weak VCD signals. The high-coordination number and dynamic property of the lanthanide complex offer an effective chirality VCD probing of biological substrates. PMID:24733785

  15. Gear shift control mechanism

    SciTech Connect

    Janson, D.A.

    1987-03-10

    A gear shift control mechanism is described comprising: multiple shift rods directed substantially parallel to one another, each rod carrying a shift fork for axial movement; a shift lever supported for pivotal movement about a first axis directed parallel to the axes of the shift rods and for pivotal movement about a second axis directed substantially perpendicular to the axes of the shift rods. The lever is moveable about the first axis and the second axis into engagement with a selected shift fork; interlock means located on each lateral side of the shift lever and mounted for pivotal movement about the first axis for blocking engagement with the shift forks; detent means for holding the shift lever in multiple predetermined angular positions about the second axis; and spring means located on a lateral side of the shift lever and mounted for pivotal movement about the first axis into interference contact with the shift forks for producing a force tending to resiliently bias the shift lever out of engagement with the selected shift fork.

  16. Oxygen-induced magnetic surface states on the ,,0001... surfaces of heavy lanthanide metals C. Schuler-Langeheine,1

    E-print Network

    Grigoriev, Alexei

    Oxygen-induced magnetic surface states on the ,,0001... surfaces of heavy lanthanide metals C. Schu adsorption on the close-packed surfaces of trivalent heavy lanthanide metals leads to the formation of well, resembling the surface states of the clean metal surfaces. For the magnetic lanthanides, these states exhibit

  17. IUPAC-NIST Solubility Data Series. 85. Transition and 12-14 Main Group Metals, Lanthanide, Actinide, and Ammonium Halates

    NASA Astrophysics Data System (ADS)

    Miyamoto, Hiroshi

    2008-06-01

    This paper is the fourth and final volume in the halate solubility series. The solubility data for halates of transition metals, lanthanides, actinides, ammonium, and metallic elements of the main groups 12-14 are reviewed. Where appropriate, binary, ternary, and multicomponent systems are critically evaluated. Most of the solubility results were obtained in water or aqueous solutions of electrolytes. The solubility in organic solvents and aqueous-organic solvent mixtures is also collected in this volume. All these data were critically examined for their reliability. The best values were selected on the basis of critical evaluations and presented in tabular form. Fitting equations and graphical plots are also provided. When numerical data were not reported in an original publication, they were read out from figures and digitized by the compilers. The quantities, units, and symbols used in this volume are in accord with IUPAC recommendations. We always reported the original data and, if necessary, transferred them into the IUPAC recommended units and symbols. The literature on the solubility data was researched through 2002. The halates of these metals play a role in industrial processes. For example, some halates are essential as catalysts, heat stabilizers, and blanching reagents for manufacturing polymer products such as textiles and resins. Some iodates are used in pyrotechnic compounds for weather modification and colored smoke generation. The nonlinear halate crystals are important in construction of optical devices.

  18. Column leaching of lanthanides from Abu Tartur phosphate ore with kinetic study

    Microsoft Academic Search

    A. T. Kandil; M. M. Aly; E. M. Moussa; A. M. Kamel; M. M. Gouda; M. N. Kouraim

    2010-01-01

    The dynamic leaching of lanthanides from a west desert phosphate ore, Egypt (Abu Tartur) by hydrochloric acid, nitric acid and sulfuric acid solutions was investigated in this study as a function of acid concentration, flow rate and the presence of some additives such as boric acid. Also the kinetics of leaching of lanthanides was investigated as a function of temperature.

  19. Lanthanide-Sensitized Luminescence as a Promising Tool in Clinical Analysis

    Microsoft Academic Search

    A. Ruiz-Medina; E. J. Llorent-Martínez; P. Ortega-Barrales; M. L. Fernández-De Córdova

    2011-01-01

    The recent applications and novelties of lanthanide-sensitized luminescence (LSL) as detection technique in clinical analysis are here reviewed. In LSL, lanthanide ions form complexes with organic compounds; in these complexes, the energy absorbed by the organic chromophore (usually, the analyte) at its characteristic excitation wavelength is transferred to a triplet state of the molecule and then transferred to a resonance

  20. Lanthanides in metallic nuclear fuels: Their behavior and methods for their control

    NASA Astrophysics Data System (ADS)

    Mariani, R. D.; Porter, D. L.; O'Holleran, T. P.; Hayes, S. L.; Kennedy, J. R.

    2011-12-01

    The thermodynamic and experimental basis is given for using dopant additives to bind lanthanides as intermetallic compounds in metallic nuclear fuels. Lanthanide fission products are a major factor in limiting the lifetime of the fuel, because they migrate to the fuel slug peripheral surface where they participate in fuel-cladding chemical interactions (FCCI) with the D9 or HT9 steel cladding. Lanthanide carryover in recycled metal fuels can accelerate FCCI, as recycled lanthanides would likely segregate from the fuel phase, putting the lanthanides in prompt contact with the cladding. In out-of-pile tests, the use of palladium was examined for binding the lanthanides, with palladium selected because of its known metallurgical properties in fuel-related systems and because of its known behavior in irradiated Experimental Breeder Reactor-II (EBR-II) fuels. Initial results confirmed that palladium may be expected to mitigate FCCI arising from lanthanides, and it has been recommended for in-pile tests. Transport phenomena responsible for lanthanide migration were also evaluated, and liquid-like behaviors were identified as being dominant. Liquid-like behaviors include transport with liquid metals, liquid metal solutions, and rapid surface transport of alloys/metals near their melting temperatures. The analysis led to establishing general criteria for selecting dopant additives and identifying tin, antimony, and tellurium as alternates for further testing.

  1. Periodic Properties of Force Constants of Small Transition-Metal and Lanthanide Clusters

    E-print Network

    Lombardi, John R.

    Periodic Properties of Force Constants of Small Transition-Metal and Lanthanide Clusters John R 2. Silver 2440 3. Gold 2441 J. Group 12 2441 1. Zinc/Cadmium/Mercury 2441 IV. Transition-Metal. Trimers 2448 VII. Higher Clusters 2450 A. Transition Metals 2450 B. Higher Lanthanide Clusters 2452 VIII

  2. Lanthanides in Metallic Nuclear Fuels: Their Behavior and Methods for Their Control

    SciTech Connect

    Robert D. Mariani; Douglas L. Porter; Thomas P. O'Holleran; Steven L. Hayes; J. Rory Kennedy

    2011-12-01

    The thermodynamic and experimental basis is given for using dopant additives to bind lanthanides as intermetallic compounds in metallic nuclear fuels. Lanthanide fission products are a major factor in limiting the lifetime of the fuel, because they migrate to the fuel slug peripheral surface where they participate in fuel-cladding chemical interactions (FCCI) with the steel cladding. Lanthanide carryover in recycled metal fuels can accelerate FCCI, as recycled lanthanides would likely segregate from the fuel phase, putting the lanthanides in prompt contact with the cladding. In out-of-pile tests we examined the use of Pd for binding the lanthanides, with Pd selected because of its known metallurgical properties in fuel related systems and because of its known behavior in irradiated EBR-II fuels. Initial results confirmed that palladium may be expected to mitigate FCCI arising from lanthanides, and it has been recommended for in-pile tests. We also evaluated transport phenomena responsible for lanthanide migration, and identified liquid-like behaviors as being dominant. Liquid-like behaviors include transport with liquid metals, liquid metal solutions, and rapid surface transport of alloys/metals near their melting temperatures. The analysis led to establishing general criteria for selecting alternate dopant additives, and identifying Sn, Sb, and Te as alternates for further testing.

  3. New reagents for coal desulfurization. Final technical report, September 1, 1990--August 31, 1991

    SciTech Connect

    Buchanan, D.H.; Kalembasa, S.; Olson, D.; Wang, S.; Warfel, L.

    1991-12-31

    The primary goal of this project was development and exploration of potential new desulfurization reagents for the removal of ``organic sulfur`` from Illinois coals by mild chemical methods. Potential new desulfurization reagents were investigated using organic sulfur compounds of the types thought to be present in coals. Reagents included low-valent metal complexes based on nickel and on iron as well as possible Single Electron Transfer reagents. Soluble coal extracts served as second generation model compounds during this reagent development project.

  4. Detection of lanthanides and actinides in solutions based on laser-induced luminescence and chemiluminescence

    NASA Astrophysics Data System (ADS)

    Izosimov, I. N.; Firsin, N. G.; Gorshkov, N. G.; Nekhoroshkov, S. N.

    2014-06-01

    This work is devoted to applications of the time-resolved laser- induced luminescence spectroscopy and time-resolved laser-induced chemiluminescence spectroscopy for detection of lanthanides and actinides. The limit of detection (LOD) of some lanthanides and actinides in solutions by the time-resolved laser luminescence spectroscopy is up to 10-13 mole/liter. Unfortunately, Pu, Np, and some U compounds do not produce luminescence in solutions, but when excited by laser radiation, they can induce chemiluminescence. The characteristics of chemiluminescence induced by excited lanthanide and actinide complexes in solutions are considered. A key problem of chemiluminescence application for lanthanide and actinide detection in solutions is the increase of the detection selectivity. This problem can be solved by using the multistep schemes of chemiluminescence excitation. It is shown that the time-resolved luminescence laser spectroscopy and chemiluminescence laser spectroscopy can be successfully used for detection of lanthanides and actinides in solutions.

  5. A peptidomimetic siRNA transfection reagent forhighly effectivegene silencing

    SciTech Connect

    Utku, Yeliz; Dehan, Elinor; Ouerfelli, Ouathek; Piano, Fabio; Zuckermann, Ronald N.; Pagano, Michele; Kirshenbaum, Kent

    2006-05-17

    RNA interference (RNAi) techniques hold forth great promisefor therapeutic silencing of deleterious genes. However, clinicalapplications of RNAi require the development of safe and efficientmethods for intracellular delivery of small interfering RNA (siRNA)oligonucleotides specific to targeted genes. We describe the use of alipitoid, a cationic oligopeptoid phospholipid conjugate, for non-viraltransfection of synthetic siRNA oligos in cell culture. Thispeptidomimetic delivery vehicle allows for efficient siRNA transfectionin a variety of human cell lines with negligible toxicity and promotesextensive downregulation of the targeted genes at both the protein andthe mRNA level. We compare the lipitoid reagent to a standard commercialtransfection reagent. The lipitoid is highly efficient even in primaryIMR-90 human lung fibroblasts in which other commercial reagents aretypically ineffective.

  6. Evaluation of novel derivatisation reagents for the analysis of oxysterols.

    PubMed

    Crick, Peter J; Aponte, Jennifer; Bentley, T William; Matthews, Ian; Wang, Yuqin; Griffiths, William J

    2014-04-11

    Oxysterols are oxidised forms of cholesterol that are intermediates in the synthesis of bile acids and steroid hormones. They are also ligands to nuclear and G protein-coupled receptors. Analysis of oxysterols in biological systems is challenging due to their low abundance coupled with their lack of a strong chromophore and poor ionisation characteristics in mass spectrometry (MS). We have previously used enzyme-assisted derivatisation for sterol analysis (EADSA) to identify and quantitate oxysterols in biological samples. This technique relies on tagging sterols with the Girard P reagent to introduce a charged quaternary ammonium group. Here, we have compared several modified Girard-like reagents and show that the permanent charge is vital for efficient MS(n) fragmentation. However, we find that the reagent can be extended to include sites for potential stable isotope labels without a loss of performance. PMID:24525124

  7. Reagents for the preparation of two oligonucleotides per synthesis (TOPS).

    PubMed Central

    Hardy, P M; Holland, D; Scott, S; Garman, A J; Newton, C R; McLean, M J

    1994-01-01

    In order to increase the efficiency of use of automated DNA synthesizers (i.e. the number of oligomers prepared per day), we have devised and prepared novel phosphoramidite reagents that contain a linking group which, while stable under the normal synthesis conditions, is cleaved under basic conditions. When one of these linkers is introduced at the desired position in the synthesis of an oligonucleotide, subsequent detritylation enables the synthesis of a second oligonucleotides sequence upon the first. During deprotection of the oligonucleotide with ammonium hydroxide, the chain is cleaved at either side of the points of introduction of the novel reagent, generating two oligonucleotides free in solution. These reagents are of particular use in applications where oligomers are used in pairs (such as PCR, chemical synthesis of genes etc.) and means that an automated synthesis facility can be used more efficiently, without the need for operator intervention, after the working day is over. Images PMID:8065912

  8. Evaluation of novel derivatisation reagents for the analysis of oxysterols

    PubMed Central

    Crick, Peter J.; Aponte, Jennifer; Bentley, T. William; Matthews, Ian; Wang, Yuqin; Griffiths, William J.

    2014-01-01

    Oxysterols are oxidised forms of cholesterol that are intermediates in the synthesis of bile acids and steroid hormones. They are also ligands to nuclear and G protein-coupled receptors. Analysis of oxysterols in biological systems is challenging due to their low abundance coupled with their lack of a strong chromophore and poor ionisation characteristics in mass spectrometry (MS). We have previously used enzyme-assisted derivatisation for sterol analysis (EADSA) to identify and quantitate oxysterols in biological samples. This technique relies on tagging sterols with the Girard P reagent to introduce a charged quaternary ammonium group. Here, we have compared several modified Girard-like reagents and show that the permanent charge is vital for efficient MSn fragmentation. However, we find that the reagent can be extended to include sites for potential stable isotope labels without a loss of performance. PMID:24525124

  9. Stereospecific synthesis of alkylidenecyclopropanes via sequential cyclopropene carbomagnesation/1,3-carbon shift

    PubMed Central

    Xie, Xiaocong; Yang, Zhe; Fox, Joseph M.

    2010-01-01

    Alkylidenecyclopropanes can be synthesized from enantiomerically enriched cyclopropene derivatives with >99% stereotransfer and good to excellent yield. The protocol comprises the stereoselective reaction of Grignard reagents with 1-alkoxymethyl-3-hydroxymethyl cyclopropenes and a stereospecific [1,3] carbon shift reaction. PMID:20462206

  10. Luminescent hybrid lanthanide sulfates and lanthanide sulfonate-carboxylates with 1,10-phenanthroline involving in-situ oxidation of 2-mercaptonbenzoic acid

    NASA Astrophysics Data System (ADS)

    Zhong, Jie-Cen; Wan, Fang; Sun, Yan-Qiong; Chen, Yi-Ping

    2015-01-01

    A series of lanthanide sulfates and lanthanide sulfonate-carboxylates, [Ln2(phen)2(SO4)3(H2O)2]n (I:Ln=Nd(1a), Sm(1b), Eu(1c), phen=1,10-phenanthroline) and [Ln(phen)(2-SBA)(BZA)]n (II: Ln=Sm(2a), Eu(2b), Dy(2c), 2-SBA=2-sulfobenzoate, BZA=benzoate) have been hydrothermally synthesized from lanthanide oxide, 2-mercaptonbenzoic acid with phen as auxiliary ligand and characterized by single-crystal X-ray diffraction, elemental analyses, IR spectra, TG analyses and luminescence spectroscopy. Interestingly, SO4 2 - anions in I came from the in situ deep oxidation of thiol groups of 2-mercaptonbenzoic acid while 2-sulfobenzoate and benzoate ligands in II from the middle oxidation and desulfuration reactions of 2-mercaptonbenzoic acid. Compounds I are organic-inorganic hybrid lanthanide sulfates, which have rare one-dimensional column-like structures. Complexes II are binuclear lanthanide sulfonate-carboxylates with 2-sulfobenzoate and benzoate as bridges and 1,10-phenanthroline as terminal. Photoluminescence studies reveal that complexes I and II exhibit strong lanthanide characteristic emission bands in the solid state at room temperature.

  11. Noninvasive MR thermometry using paramagnetic lanthanide complexes of 1,4,7,10-tetraazacyclodoecane-alpha,alpha',alpha'',alpha'''-tetramethyl-1,4,7,10-tetraacetic acid (DOTMA4-).

    PubMed

    Hekmatyar, S K; Hopewell, Paige; Pakin, Sait Kubilay; Babsky, Andriy; Bansal, Navin

    2005-02-01

    Noninvasive techniques to monitor temperature have numerous useful biomedical applications. However, MR thermometry techniques based on the chemical shift, relaxation rates, and molecular diffusion rate of the water 1H signal suffer from poor thermal resolution. The feasibility of MR thermometry based on the strong temperature dependence of the hyperfine-shifted 1H signal from the paramagnetic lanthanide complex thulium-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate (TmDOTA-) was recently demonstrated. The use of paramagnetic lanthanide complexes for MR thermometry can be further enhanced by improving the signal-to-noise ratio (SNR) of the observed signal. In this study, the use of lanthanide complexes of a methyl-substituted analog of DOTA4-, 1,4,7,10-tetramethyl 1,4,7,10-tetra azacyclodoecane-1,4,7,10-tetraacetic acetate (DOTMA4-) was evaluated. DOTMA4- complexes have 12 magnetically equivalent methyl protons, which provide an intense and sharper resonance compared to the corresponding DOTA- complexes. Experiments with paramagnetic Pr3+, Yb3+, Tb3+, Dy3+, and Tm3+ complexes of DOTMA4- showed that the Tm3+ complex is most favorable for MR thermometery because of the high temperature dependence of its chemical shift and its relatively narrow linewidth. The chemical shift of the methyl 1H signal from TmDOTMA- was approximately 60 times more sensitive to temperature than the water 1H shift and was insensitive to changes in concentration, pH, [Ca2+], or the presence of other ions and macromolecules. The application of TmDOTMA- for measuring temperature in a subcutaneously implanted tumor model was demonstrated. Lastly, the feasibility of obtaining 3D images from the methyl 1H resonance of TmDOTMA- was demonstrated in phantom and live animal experiments. Overall, TmDOTMA- appears to be a promising probe for MR thermometry in vivo. PMID:15678553

  12. Lanthanides inhibit the human noradrenaline, 5-hydroxytryptamine and dopamine transporters.

    PubMed

    Bryan-Lluka, L J; Bönisch, H

    1997-06-01

    Transporters for the monoamine neurotransmitters, including noradrenaline, 5-hydroxytryptamine [5-HT] and dopamine, have twelve transmembrane spanning regions and cotransport Na+ and Cl- ions. Another family of Na(+)-dependent transporters is that containing the Na+/glucose and Na+/proline cotransporters that are found in the epithelial cells of renal and intestinal brush border membranes. It has been shown that various trivalent lanthanides can substitute for Na+ for transport of glucose and proline. The aim of this study was to determine the effects of lanthanides on the activities of the human noradrenaline, 5-HT and dopamine transporters. Cultured cells were incubated for 2 min with 10 nM 3H-noradrenaline (SK-N-SH-SY5Y human neuroblastoma cells), 3H-5-HT (JAR human placental choriocarcinoma cells) or 3H-dopamine (COS-7 cells transfected with the cDNA of the human dopamine transporter). Specific amine uptake was determined as the difference between accumulation of the amine in the cells in the absence and presence of a corresponding uptake inhibitor. Under both isotonic (150 mM NaCl or LiCl or 90 mM lanthanide salt) and hypertonic (150 mM NaCl +100 mM LiCl, 250 mM LiCl or 150 mM lanthanide salt) conditions, replacement of Na+ by Li+, La3+, Eu3+ or Sm3+ abolished the specific uptake of noradrenaline in SK-N-SH-SY5Y cells and replacement of Na+ by Li+ or Eu3+ decreased the specific uptake of 5-HT in JAR cells by 94-100% and that of dopamine in transfected COS-7 cells by 95-99%. The direct effects of Eu3+ (with Na+ present) on the human noradrenaline transporter in SK-N-SH-SY5Y cells were also examined. Eu3+ inhibited noradrenaline uptake into the cells (IC50 2.6 mM) and nisoxetine binding to crude membranes of SK-N-SH-SY5Y cells (IC50 4.7 mM) with similar potencies. Further experiments showed that 4.5 mM EuCl3 in the presence of 150 mM Na+ caused a 3.5-fold increase in the K(m) of noradrenaline and no change in the maximal rate of noradrenaline uptake. EuCl3 (4.5 mM) also caused a pronounced inhibition of the Na(+)-dependent stimulation of noradrenaline uptake by SK-N-SH-SY5Y cells. It can be concluded from these data that, in contrast with the Na+/glucose and Na+/proline cotransporters, the lanthanides cannot substitute for Na+ in the transport of substrates by the monoamine neurotransmitter transporters and that the lanthanides inhibit the latter transporters by interacting with sites of the transporters involved in amine and Na+ binding. PMID:9205953

  13. The low-temperature heat capacity of some lanthanide zirconates

    Microsoft Academic Search

    S. Lutique; R. J. M. Konings; J.-C. Krupa; A. C. G. van Genderen; J. C. van Miltenburg; F. Wastin

    2004-01-01

    The heat capacities of the lanthanide zirconates Gd2Zr2O7 and Eu2Zr2O7 with pyrochlore structure were measured by adiabatic calorimetry and the hybrid adiabatic relaxation method in the temperature range (0.3 to 400) K. A thermal anomaly was observed for Gd2Zr2O7 below T=15 K. From the measurements the thermodynamic functions of Gd2Zr2O7 and Eu2Zr2O7 were determined. By combining our results with the

  14. Centrifugal atomization of lanthanide materials for cryogenic coolers

    SciTech Connect

    Osborne, M.G.

    1994-01-04

    Until recently, Pb was the preferred heat exchanger matrix material used in low temperature cryocoolers; however, the heat capacity of Pb drops drastically below {approximately}15K and new matrix materials based on the lanthanide elements have been developed. These materials magnetically order at low temperatures and the entropy change associated with ordering contributes to the materials` heat capacities. The drawback to widespread use of lanthanide intermetallic compounds in cryocoolers has been the difficulty in manufacturing high-quality particulates. The purpose of this project was to develop a technique for producing high-quality powders of lanthanide metals and lanthanide intermetallic compounds for use in cryocooler heat exchangers. A series of atomization experiments was performed using Er{sub 3}Ni, Nd, Nd{sub 3}Ni, and (Er{sub 0.5}Nd{sub 0.5}){sub 3}Ni. Atomization of these materials resulted in particles ranging from mostly spherical to extremely flattened. Analyses of size distributions for the experiments indicate that increased atomization disk speed and superheat result in smaller mean particle diameters and narrower size distributions. Chemical analyses of the atomized powders indicate that the CA/RQB technique produces particulate with much lower interstitial contamination than other techniques. The Er{sub 3}Ni and Nd{sub 3}Ni powders were predominantly of the desired phase and the (Er{sub 0.5}Nd{sub 0.5}){sub 3}Ni powder had one major and possibly three minor phases. The solidification morphology is typically fine dendritic or cellular with finer microstructure spacings near the particle surfaces. The Er{sub 3}Ni powders have higher heat capacities than gas atomized powders reported in literature. The heat capacity of Nd{sub 3}Ni has a peak which does not degrade dramatically with processing. The (Er{sub 0.5}Nd{sub 0.5}){sub 3}Ni material has a higher heat capacity compared to Er{sub 3}Ni, Nd{sub 3}Ni, and Nd at temperatures above 10K.

  15. A family of 13 tetranuclear zinc(II)-lanthanide(III) complexes of a [3+3] Schiff-base macrocycle derived from 1,4-diformyl-2,3-dihydroxybenzene.

    PubMed

    Feltham, Humphrey L C; Klöwer, Frederik; Cameron, Scott A; Larsen, David S; Lan, Yanhua; Tropiano, Manuel; Faulkner, Stephen; Powell, Annie K; Brooker, Sally

    2011-11-21

    A family of thirteen tetranuclear heterometallic zinc(II)-lanthanide(III) complexes of the hexa-imine macrocycle (L(Pr))(6-), with general formula Zn(II)(3)Ln(III)(L(Pr))(NO(3))(3)·xsolvents (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm or Yb), were prepared in a one-pot synthesis using a 3:1:3:3 reaction of zinc(II) acetate, the appropriate lanthanide(III) nitrate, the dialdehyde 1,4-diformyl-2,3-dihydroxybenzene (H(2)L(1)) and 1,3-diaminopropane. A hexanuclear homometallic zinc(II) macrocyclic complex [Zn(6)(L(Pr))(OAc)(5)(OH)(H(2)O)]·3H(2)O was obtained using a 2:0:1:1 ratio of the same reagents. A control experiment using a 1:0:1:1 ratio failed to generate the lanthanide-free [Zn(3)(L(Pr))] macrocyclic complex. The reaction of H(2)L(1) and zinc(II) acetate in a 1:1 ratio yielded the pentanuclear homometallic complex of the dialdehyde H(2)L(1), [Zn(5)(L(1))(5)(H(2)O)(6)]·3H(2)O. An X-ray crystal structure determination revealed [Zn(3)(II)Pr(III)(L(Pr))(NO(3))(2)(DMF)(3)](NO(3))·0.9DMF has the large ten-coordinate lanthanide(III) ion bound in the central O(6) site with two bidentate nitrate anions completing the O(10) coordination sphere. The three square pyramidal zinc(II) ions are in the outer N(2)O(2) sites with a fifth donor from DMF. Measurement of the magnetic properties of [Zn(II)(3)Dy(III)(L(Pr))(NO(3))(3)(MeOH)(3)]·4H(2)O with a weak external dc field showed that it has a frequency-dependent out-of-phase component of ac susceptibility, indicative of slow relaxation of the magnetization (SMM behaviour). Likewise, the Er and Yb analogues are field-induced SMMs; the latter is only the second example of a Yb-based SMM. The neodymium, ytterbium and erbium complexes are luminescent in the solid phase, but only the ytterbium and neodymium complexes show strong lanthanide-centred luminescence in DMF solution. PMID:21935549

  16. Thermodynamics and extraction modeling of trivalent lanthanides in the nuclear fuel cycle

    SciTech Connect

    Levitskaia, T.G.; Chatterjee, S.; Valerio, E.L.; Robinson, T.A. [Pacific Northwest National Laboratory, 902 Battelle Blvd, PO Box 999, MSIN P7-25 Richland, WA 99352 (United States)

    2013-07-01

    In this investigation, a combination of VPO (Vapor Pressure Osmometry) and water activity methods was applied to measure water activity and osmotic coefficients of binary lanthanide nitrate solutions at a temperature of 25 C. degrees. It was observed that the nature of the lanthanide nitrate has pronounced effect on the water activity in solution. In the solutions with the same Ln(NO{sub 3}){sub 3} molality, water activity is decreased in the order from the light to heavy lanthanides. This trend was explained by the contraction of the lanthanide ionic radii in the same order resulting in the [Ln(H{sub 2}O){sub n}]{sup 3+} (aq) hydration number of 9 for the early (La-Sm) and 8 for the late (Dy-Lu) lanthanides, with the intermediate metals exhibiting a mixture of eight and nine coordinate molecules. This results in the dissimilar effect of the light and heavy lanthanides on the water structure manifesting in the systematic changes of the water activity in the series of concentrated lanthanide solutions. Experimental water activity and osmotic coefficient data agree well with the literature for both 1:1 and 3:1 electrolyte systems. The Pitzer parameters obtained fitting these data are in an excellent agreement with the literature reported values for Ln(NO{sub 3}){sub 3} solutions.

  17. The Clinical Proteomic Technologies for Cancer | Reagent Opportunities

    Cancer.gov

    In efforts to provide an open data platform for affinity reagents NCI’s Antibody Characterization Program has begun to utilize Material Cooperative Research and Development Agreements (M-CRADAs) through SAIC-Frederick, Inc so that commercial vendors can use the antibody characterization pipeline.

  18. Glycosyl phenylthiosulfonates (Glyco-PTS): novel reagents for glycoprotein synthesis

    E-print Network

    Davis, Ben G.

    Glycosyl phenylthiosulfonates (Glyco-PTS): novel reagents for glycoprotein synthesis David P- thesis of glycoproteins offers certain key advantages,2 not least of which is more ready access to pure glycoprotein glycoforms.3 Several alternative and complementary strategies that provide access to pure

  19. Construction of oligonucleotide microarrays (biochip) using heterobifunctional reagents.

    PubMed

    Choithani, Jyoti; Vaijayanthi, B; Kumar, Pradeep; Gupta, Kailash Chand

    2007-01-01

    A number of hetero- and homobifunctional reagents have been reported to immobilize biomolecules on a variety of supports. However, efforts are on to search for a method, which is relatively simple, involving minimum of steps, cost effective, easy to reproduce, and that produces stable oligonucleotide arrays. Two new reagents, viz., [N-(2-trifluoroethanesulfonatoethyl)-N-(methyl)-triethoxysilylpropyl-3-amine], and [N-(3-trifluoroethanesulfonyloxypropyl)anthraquinone-2-carboxamide] have been designed considering the above points. These reagents contain different functional groups at their two ends. In [N-(2-trifluoroethanesulfonatoethyl)-N-(methyl)-triethoxysilylpropyl-3-amine], one end (triethoxysilyl) is capable of binding to the virgin glass surface and the other one consists of trifluoroethanesulfonate (tresyl) function specific toward aminoalkyl and mercaptoalkyl functionalities, which are easy to introduce at the 3'- or 5'-end of oligonucleotides. Likewise, in [N-(3-trifluoroethanesulfonyloxypropyl)anthraquinone-2-carboxamide], one end consists of photoactivatable moiety (anthraquinone) capable of reacting to a C-H containing surface and the tresyl function at the other end reacts specifically with aminoalkyl and mercaptoalkyl functionalities in modified oligonucleotides. These reagents have successfully been utilized to construct a number of oligonucleotide arrays and subsequently used for the detection of mismatches. PMID:17984518

  20. CPTC expand scope of Reagents and Resources Core

    Cancer.gov

    Whether in determining if a women is pregnant or not by measuring human chorionic gonadotropin or determining whether someone is HIV positive, antibodies and other affinity reagents play a key role both in diagnostic decision making and advancing the research field.

  1. Methods and reagents. Degraded DNA and gel tornados.

    PubMed

    Hengen, P N

    1997-04-01

    Methods and reagents is a unique monthly column that highlights current discussions in the newsgroup bionet.molbio.methds-reagnts, available on the Internet. This month's column discusses a case of inexplicable DNA degradation and tornados seen in agarose gels. For details on how to partake in the newsgroup, see the accompanying box. PMID:9149534

  2. Purification of lanthanides for double beta decay experiments

    SciTech Connect

    Polischuk, O. G. [Institute for Nuclear Research, MSP 03680 Kyiv, Ukraine and INFN, Section of Rome, La Sapienza, I-00185 Rome (Italy)] [Institute for Nuclear Research, MSP 03680 Kyiv, Ukraine and INFN, Section of Rome, La Sapienza, I-00185 Rome (Italy); Barabash, A. S. [Institute of Theoretical and Experimental Physics, 117259 Moscow (Russian Federation)] [Institute of Theoretical and Experimental Physics, 117259 Moscow (Russian Federation); Belli, P. [INFN, Section of Rome Tor Vergata, I-00133 Rome (Italy)] [INFN, Section of Rome Tor Vergata, I-00133 Rome (Italy); Bernabei, R. [INFN, Section of Rome Tor Vergata, I-00133 Rome, Italy and Department of Physics, University of Rome Tor Vergata, I-00133 Rome (Italy)] [INFN, Section of Rome Tor Vergata, I-00133 Rome, Italy and Department of Physics, University of Rome Tor Vergata, I-00133 Rome (Italy); Boiko, R. S.; Danevich, F. A.; Mokina, V. M.; Poda, D. V.; Tretyak, V. I. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine)] [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Cappella, F.; Incicchitti, A. [INFN, Section of Rome La Sapienza, I-00185 Rome, Italy and Department of Physics, University of Rome La Sapienza, I-00185 Rome (Italy)] [INFN, Section of Rome La Sapienza, I-00185 Rome, Italy and Department of Physics, University of Rome La Sapienza, I-00185 Rome (Italy); Cerulli, R.; Laubenstein, M.; Nisi, S. [INFN, Gran Sasso National Laboratories, I-67100 Assergi (Aq) (Italy)] [INFN, Gran Sasso National Laboratories, I-67100 Assergi (Aq) (Italy)

    2013-08-08

    There are several potentially double beta active isotopes among the lanthanide elements. However, even high purity grade lanthanide compounds contain {sup 238}U, {sup 226}Ra and {sup 232,228}Th typically on the level of ? (0.1 - 1) Bq/kg. The liquid-liquid extraction technique was used to remove traces of U, Ra and Th from CeO{sub 2}, Nd{sub 2}O{sub 3} and Gd{sub 2}O{sub 3}. The radioactive contamination of the samples before and after the purification was tested by using ultra-low-background HPGe ? spectrometry at the underground Gran Sasso National Laboratories of the INFN (Italy). After the purification the radioactive contamination of gadolinium oxide by Ra and Th was decreased at least one order of magnitude. The efficiency of the approach to purify cerium oxide from Ra was on same level, while the radioactive contamination of neodymium sample before and after the purification is below the sensitivity of analytical methods. The purification method is much less efficient for chemically very similar radioactive elements like lanthanum, lutetium and actinium. R and D of the methods to remove the pollutions with improved efficiency is in progress.

  3. Purification of lanthanides for double beta decay experiments

    NASA Astrophysics Data System (ADS)

    Polischuk, O. G.; Barabash, A. S.; Belli, P.; Bernabei, R.; Boiko, R. S.; Cappella, F.; Cerulli, R.; Danevich, F. A.; Incicchitti, A.; Laubenstein, M.; Mokina, V. M.; Nisi, S.; Poda, D. V.; Tretyak, V. I.

    2013-08-01

    There are several potentially double beta active isotopes among the lanthanide elements. However, even high purity grade lanthanide compounds contain 238U, 226Ra and 232,228Th typically on the level of ˜ (0.1 - 1) Bq/kg. The liquid-liquid extraction technique was used to remove traces of U, Ra and Th from CeO2, Nd2O3 and Gd2O3. The radioactive contamination of the samples before and after the purification was tested by using ultra-low-background HPGe ? spectrometry at the underground Gran Sasso National Laboratories of the INFN (Italy). After the purification the radioactive contamination of gadolinium oxide by Ra and Th was decreased at least one order of magnitude. The efficiency of the approach to purify cerium oxide from Ra was on same level, while the radioactive contamination of neodymium sample before and after the purification is below the sensitivity of analytical methods. The purification method is much less efficient for chemically very similar radioactive elements like lanthanum, lutetium and actinium. R&D of the methods to remove the pollutions with improved efficiency is in progress.

  4. Stabilization of actinides and lanthanides in unusually high oxidation states

    SciTech Connect

    Eller, P.G.; Penneman, R.A.

    1986-01-01

    Chemical environments can be chosen which stabilize actinides and lanthanides in unusually high or low oxidation states and in unusual coordination. In many cases, one can rationalize the observed species as resulting from strong charge/size influences provided by specific sites in host lattices (e.g., Tb(IV) in BaTbO/sub 3/ or Am(IV) in polytungstate anions). In other cases, the unusual species can be considered from an acid-base viewpoint (e.g., U(III) in AsF/sub 5//HF solution or Pu(VII) in Li/sub 5/PuO/sub 6/). In still other cases, an interplay of steric and redox effects can lead to interesting comparisons (e.g., instability of double fluoride salts of Pu(V) and Pu(VI) relative to U, Np, and Am analogues). Generalized ways to rationalize compounds containing actinides and lanthanides in unusual valences (particularly high valences), including the above and numerous other examples, will form the focus of this paper. Recently developed methods for synthesizing high valent f-element fluorides using superoxidizers and superacids at low temperatures will also be described. 65 refs., 8 figs., 9 tabs.

  5. Basic understanding of the lanthanide related upconversion emissions

    NASA Astrophysics Data System (ADS)

    Dong, Hao; Sun, Ling-Dong; Yan, Chun-Hua

    2013-06-01

    With abundant energy levels of 4f electron configurations, trivalent lanthanide ions (Ln3+) are endowed with unique and fascinating luminescent properties. Inheriting the native transition behaviour of the lanthanide ions, Ln3+ based nanomaterials have aroused great interest for a wide range of applications, including lighting and displays, optical fibers and amplifiers, responsive luminescent stains for biomedical analysis, in vivo and in vitro imaging, and enhancement for silicon solar cell devices. It should be noted that the application depends completely on the corresponding luminescent behaviour. To deepen the understanding of the luminescent mechanism is important for the developing of the field and the design of new Ln3+ based luminescent materials toward applications. In this review, we focused mainly on the recent developments on upconversion (UC) emission studies. Firstly, the emphasis was put on the introduction of basic luminescent properties of Ln3+ with f-f transitions, and then the corresponding mechanisms and properties of UC emission were discussed in detail, the potential researches with respect to UC mechanisms and properties were finally outlined.

  6. Synthesis and properties of mixed lanthanide chromite perovskites

    SciTech Connect

    Armstrong, T.R.; Stevenson, J.W.; Hasinska, Katarzyna; McCready, D.E. [Pacific Northwest National Lab., Richland, WA (United States). Materials and Chemical Sciences Dept.

    1998-12-01

    Calcium-substituted lanthanum chromites were synthesized using a mixed lanthanide precursor composed primarily of La, Nd, Ce, and Pr. The thermal and electrical properties of these materials were measured and compared to similar chromites synthesized with lanthanum nitrate. The presence of Nd and Pr in the chromite resulted in a lowering of the thermal expansion coefficient and an increase in the temperature necessary to attain full density. Arrhenius plots of electrical conductivity were nonlinear with an inflection at temperatures between 625 and 750 C, indicating an increase in the carrier concentration with temperature. The increase in carrier concentration was consistent with the reduction of Ce{sup 4+} to ce{sup 3+}, resulting in a corresponding increase in Cr{sup 4+} in order to preserve electrical neutrality. The presence of both tri- and tetravalent Ce was substantiated using dilatometry measurements and X-ray photoelectron spectroscopy. The mixed lanthanide precursor is a possible low cost alternative for the synthesis of rare earth chromites for applications such as interconnects in solid oxide fuel cells.

  7. Effective Atomic Numbers of Lanthanides with Gamma Radiation for Photon Energy Absorption

    NASA Astrophysics Data System (ADS)

    Shantappa, Anil; Hanagodimath, S. M.

    Effective atomic numbers for photon energy absorption, ZPEA,eff have been calculated for photon from 1 keV to 20 MeV for selected oxides of lanthanides, such as Lanthanum oxide, Cerium oxide, Samarium oxide, Europium oxide, Dysprosium oxide, Thulium oxide, Ytterbium oxide. The ZPEA,eff values then compared with ZPI,eff for photon interaction. The ZPEA,eff values have been found to change with energy and composition of selected lanthanides. Oxides of lanthanides are considered as better shielding materials to the exposure of gamma radiation. The values of effective atomic number for photon energy absorption help in the calculation of absorbed dose.

  8. Gadolinium chloride-induced shifts in intrahepatic distributions of liposomes.

    PubMed

    Lázár, G; van Galen, M; Scherphof, G L

    1989-05-10

    Intravenously administered gadolinium chloride caused only a slight decrease in the rate of elimination of small unilamellar liposomes from the blood and had no influence on the total hepatic uptake of these vesicles, but did alter their intrahepatic distribution substantially. Uptake by the non-parenchymal cells was substantially decreased, whereas uptake by the parenchymal cells showed a concomitant increase. Our earlier observations (Roerdink et al. (1981) Biochim. Biophys. Acta 677, 79-89) on the effect of lanthanides on the in vivo distribution of multilamellar liposomes have been extended, in that we demonstrate, in addition to the drop in elimination rate from the blood and in the over-all hepatic uptake, a shift of liposome distribution within the Kupffer cell population. While the larger Kupffer cells, which normally take up a major fraction of an injected liposome dose, were strongly inhibited in liposome uptake, the more numerous small macrophages showed a 3-4-fold increase in uptake. PMID:2713404

  9. Manufacturing of lab-on-a-chip devices : characterizing seals for on-board reagent delivery

    E-print Network

    Inamdar, Tejas Satish

    2013-01-01

    The reagent delivery mechanism in a point-of-care, HIV diagnostic, microfluidic device is studied. Reagents held in an aluminum pack are released on the opening of a fluidic seal. Fluidic seals, controlling the flow of ...

  10. 41 CFR 101-42.1102-5 - Drugs, biologicals, and reagents other than controlled substances.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...When surplus drugs, biologicals, and reagents are required...air and water pollution control authorities. (3...Destruction of surplus drugs, biologicals, and reagents shall...employees of the agency. The controls which the...

  11. A New Spray Reagent for Paper Chromatography of Polyols and Cetoses

    Microsoft Academic Search

    Paul Godin

    1954-01-01

    VARIOUS reagents for indicating polyols in paper chromatography have been proposed by Hough, Buchanan et al. and Hockenhull1. These reagents all have the disadvantage of reacting also with the sugars, not distinguishing them from the polyols.

  12. 21 CFR 866.3390 - Neisseria spp. direct serological test reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3390 Neisseria spp. direct serological test reagents. (a)...

  13. 21 CFR 866.3820 - Treponema pallidum non-treponemal test reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3820 Treponema pallidum non-treponemal test reagents. (a)...

  14. 21 CFR 866.3830 - Treponema pallidum tre-ponemal test reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3830 Treponema pallidum tre-ponemal test reagents. (a)...

  15. 21 CFR 866.3830 - Treponema pallidum tre-ponemal test reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3830 Treponema pallidum tre-ponemal test reagents. (a)...

  16. 21 CFR 866.3830 - Treponema pallidum tre-ponemal test reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3830 Treponema pallidum tre-ponemal test reagents. (a)...

  17. 27 CFR 20.117 - Reagent alcohol general-use formula.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... false Reagent alcohol general-use formula. 20.117 Section 20.117 Alcohol...DISTRIBUTION AND USE OF DENATURED ALCOHOL AND RUM Formulas and Statements of Process General-Use Formulas § 20.117 Reagent alcohol...

  18. 27 CFR 20.117 - Reagent alcohol general-use formula.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... false Reagent alcohol general-use formula. 20.117 Section 20.117 Alcohol...DISTRIBUTION AND USE OF DENATURED ALCOHOL AND RUM Formulas and Statements of Process General-Use Formulas § 20.117 Reagent alcohol...

  19. 27 CFR 20.117 - Reagent alcohol general-use formula.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... false Reagent alcohol general-use formula. 20.117 Section 20.117 Alcohol...DISTRIBUTION AND USE OF DENATURED ALCOHOL AND RUM Formulas and Statements of Process General-Use Formulas § 20.117 Reagent alcohol...

  20. 27 CFR 20.117 - Reagent alcohol general-use formula.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... false Reagent alcohol general-use formula. 20.117 Section 20.117 Alcohol...DISTRIBUTION AND USE OF DENATURED ALCOHOL AND RUM Formulas and Statements of Process General-Use Formulas § 20.117 Reagent alcohol...

  1. 27 CFR 20.117 - Reagent alcohol general-use formula.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... false Reagent alcohol general-use formula. 20.117 Section 20.117 Alcohol...DISTRIBUTION AND USE OF DENATURED ALCOHOL AND RUM Formulas and Statements of Process General-Use Formulas § 20.117 Reagent alcohol...

  2. Making Shifts toward Proficiency

    ERIC Educational Resources Information Center

    McGatha, Maggie B.; Bay-Williams, Jennifer M.

    2013-01-01

    The Leading for Mathematical Proficiency (LMP) Framework (Bay-Williams et al.) has three components: (1) The Standards for Mathematical Practice; (2) Shifts in classroom practice; and (3) Teaching skills. This article briefly describes each component of the LMP framework and then focuses more in depth on the second component, the shifts in…

  3. Shift work, cancer and \\

    Microsoft Academic Search

    Thomas C Erren

    2010-01-01

    This commentary intends to instigate discussions about upcoming epidemiologic research, and its interpretation, into putative links between shift work, involving circadian disruption or chronodisruption [CD], and the development of internal cancers. In 2007, the International Agency for Research on Cancer (IARC) convened an expert group to examine the carcinogenicity of shift work, inter alia characterized by light exposures at unusual

  4. Shifting scintillator neutron detector

    DOEpatents

    Clonts, Lloyd G; Cooper, Ronald G; Crow, Jr., Morris Lowell; Hannah, Bruce W; Hodges, Jason P; Richards, John D; Riedel, Richard A

    2014-03-04

    Provided are sensors and methods for detecting thermal neutrons. Provided is an apparatus having a scintillator for absorbing a neutron, the scintillator having a back side for discharging a scintillation light of a first wavelength in response to the absorbed neutron, an array of wavelength-shifting fibers proximate to the back side of the scintillator for shifting the scintillation light of the first wavelength to light of a second wavelength, the wavelength-shifting fibers being disposed in a two-dimensional pattern and defining a plurality of scattering plane pixels where the wavelength-shifting fibers overlap, a plurality of photomultiplier tubes, in coded optical communication with the wavelength-shifting fibers, for converting the light of the second wavelength to an electronic signal, and a processor for processing the electronic signal to identify one of the plurality of scattering plane pixels as indicative of a position within the scintillator where the neutron was absorbed.

  5. Modelling studies in aqueous solution of lanthanide (III) chelates designed for nuclear magnetic resonance biomedical applications

    NASA Astrophysics Data System (ADS)

    Henriques, E. S.; Geraldes, C. F. G. C.; Ramos, M. J.

    Molecular dynamics simulations and complementary modelling studies have been carried out for the [Gd(DOTA)·(H2O)]- and [Tm(DOTP)]5- chelates in aqueous media, to provide a better understanding of several structural and dynamical properties of these versatile nuclear magnetic resonance (NMR) probes, including coordination shells and corresponding water exchange mechanisms, and interactions of these complexes with alkali metal ions. This knowledge is of key importance in the areas of 1H relaxation and shift reagents for NMR applications in medical diagnosis. A new refinement of our own previously developed set of parameters for these Ln(III) chelates has been used, and is reported here. Calculations of water mean residence times suggest a reassessment of the characterization of the chelates' second coordination shell, one where the simple spherical distribution model is discarded in favour of a more detailed approach. Na+ probe interaction maps are in good agreement with the available site location predictions derived from 23Na NMR shifts.

  6. Lanthanide-Mediated Dephosphorylation Used for Peptide Cleavage during Solid Phase Peptide Synthesis

    PubMed Central

    Yoo, Byunghee; Pagel, Mark D.

    2014-01-01

    Lanthanide(III) ions can accelerate the hydrolysis of phosphomonoesters and phosphodiesters in neutral aqueous solution. In this paper, lanthanide-mediated dephosphorylation has been applied in aqueous media as an orthogonal cleavage condition that can be employed in conventional solid phase peptide synthesis (SPPS). A phosphorylated polymeric support for SPPS was developed using Boc chemistry. The cleavage of resin-bound phosphates was investigated with the addition of Eu(III), Yb(III), acid or base, a mixture of solvents or different temperatures. To demonstrate the utility of this approach for SPPS, a peptide sequence was synthesized on a phosphorylated polymeric support and quantitatively cleaved with lanthanide ions in neutral aqueous media. The protecting groups for side chains were retained during peptide cleavage using lanthanide ions. This new methodology provides a mild orthogonal cleavage condition of phosphoester as a linker during SPPS. PMID:23549296

  7. Lanthanide ecotoxicity: First attempt to measure environmental risk for aquatic organisms.

    PubMed

    González, Verónica; Vignati, Davide A L; Pons, Marie-Noelle; Montarges-Pelletier, Emmanuelle; Bojic, Clément; Giamberini, Laure

    2015-04-01

    The geochemical cycles of lanthanides are being disrupted by increasing global production and human use, but their ecotoxicity is not fully characterized. In this study, the sensitivity of Aliivibrio fischeri and Pseudokirchneriella subcapitata to lanthanides increased with atomic number, while Daphnia magna, Heterocypris incongruens, Brachionus calyciflorus and Hydra attenuata were equally sensitive to the tested elements. In some cases, a marked decrease in exposure concentrations was observed over test duration and duly considered in calculating effect concentrations and predicted no effect concentrations (PNEC) for hazard and risk assessment. Comparison of PNEC with measured environmental concentrations indicate that, for the present, environmental risks deriving from lanthanides should be limited to some hotspots (e.g., downstream of wastewater treatment plants). However, considering the increasing environmental concentrations of lanthanides, the associated risks could become higher in the future. Ecotoxicological and risk assessment studies, along with monitoring, are required for properly managing these emerging contaminants. PMID:25645063

  8. Engineering Encodable Lanthanide-Binding Tags (LBTs) into Loop Regions of Proteins

    E-print Network

    Barthelmes, Katja

    Lanthanide-binding tags (LBTs) are valuable tools for investigation of protein structure, function, and dynamics by NMR spectroscopy, X-ray crystallography, and luminescence studies. We have inserted LBTs into three different ...

  9. Structural and electronic analysis of lanthanide complexes: Reactivity may not necessarily be

    E-print Network

    Paris-Sud XI, Université de

    1 Structural and electronic analysis of lanthanide complexes: Reactivity may not necessarily suggest a significant, albeit indirect, contribution of f electrons to bonding. Relativistic effects were earth; complexes; catalysis; electronic structure; theory Received: Running title: Electronic structure

  10. NOVEL APPROACH TO METAL-HUMIC COMPLEXATION STUDIES BY LANTHANID ION PROBE SPECTROSCOPY

    EPA Science Inventory

    Naturally occurring humic substances are known to be potentially strong binders of metals in the environment. ensitive spectroscopic technique, based on the unique luminescence properties of the tripositive lanthanide metal ions, has been developed to selectively probe metal bind...

  11. Patterns in the stability of the lower oxidation states of the actinides and lanthanides

    SciTech Connect

    Mikheev, N.B.; Auerman, L.N.; Ionova, G.V.; Korshunov, B.G.; Spitsyn, V.I.

    1986-09-01

    The authors compare the first half of the lanthanides and the second half of the actinides by considering the specifics of the electronic structure of the valence atoms of the f-, d-, and s-orbitals, consisting of he following: The lanthanides from praseodymium to europium and from dysprosium to ytterbium, as well as the actinides from californium to nobelium, have the same electronic configuration f /SUP n/ s/sub 2/ in the state of free neutral atoms, which corresponds to their divalent state. On the basis of a consideration of the energy characteristics of the valence orbitals of the elements of the lanthanide and actinide famililies and as a result of an experimental determination of the standard oxidation potential of these elements, the authors consider the profound similarity between the elements of the first half of the lanthanide family and the second half of the actinide family to be established.

  12. 21 CFR 864.9225 - Cell-freezing apparatus and reagents for in vitro diagnostic use.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Cell-freezing apparatus and reagents for...Blood and Blood Products § 864.9225 Cell-freezing apparatus and reagents for in...diagnostic use. (a) Identification. Cell-freezing apparatus and reagents...

  13. 21 CFR 864.9225 - Cell-freezing apparatus and reagents for in vitro diagnostic use.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Cell-freezing apparatus and reagents for...Blood and Blood Products § 864.9225 Cell-freezing apparatus and reagents for in...diagnostic use. (a) Identification. Cell-freezing apparatus and reagents...

  14. 21 CFR 864.9225 - Cell-freezing apparatus and reagents for in vitro diagnostic use.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Cell-freezing apparatus and reagents for...Blood and Blood Products § 864.9225 Cell-freezing apparatus and reagents for in...diagnostic use. (a) Identification. Cell-freezing apparatus and reagents...

  15. 21 CFR 864.9225 - Cell-freezing apparatus and reagents for in vitro diagnostic use.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Cell-freezing apparatus and reagents for...Blood and Blood Products § 864.9225 Cell-freezing apparatus and reagents for in...diagnostic use. (a) Identification. Cell-freezing apparatus and reagents...

  16. 21 CFR 864.9225 - Cell-freezing apparatus and reagents for in vitro diagnostic use.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Cell-freezing apparatus and reagents for...Blood and Blood Products § 864.9225 Cell-freezing apparatus and reagents for in...diagnostic use. (a) Identification. Cell-freezing apparatus and reagents...

  17. Adding reagent to droplets with controlled rupture of encapsulated double emulsions

    PubMed Central

    Sciambi, Adam; Abate, Adam R.

    2013-01-01

    We present a method to add reagent to microfluidic droplets by enveloping them as a double emulsions in reagent-filled droplets and then rupturing them with an electric field. When the double emulsions rupture, they release their contents into the enveloping droplets, ensuring mixing with reagent while limiting cross-droplet contamination. PMID:24404045

  18. Swine Toolkit Plans and Progress for the US Veterinary Immune Reagent Network

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The US Veterinary Immune Reagent Network (http://www.umass.edu/vetimm/) was established to address the lack of immunological reagents specific for ruminant, porcine, poultry, equine and aquaculture species and accordingly has set a minimum goal of 20 reagents per species group. Current plans are to...

  19. Imipramine hydrochloride and desipramine hydrochloride as new reagents for detection of microamounts of blood in urine

    Microsoft Academic Search

    Akheel A Syed; Mohammed F Silwadi; Bibi A Khatoon

    2002-01-01

    Benzidine and o-tolidine, the hazardous carcinogens are still in use for the detection of blood in urine. Development of safer substitutes are of paramount importance. Unfortunately, the alternate available reagents lack specificity, sensitivity and reproducibility. Imipramine hydrochloride (IPH) and desipramine hydrochloride (DPH) are proposed as new reagents for the detection of blood in urine. Both the reagents impact to blood

  20. Environmental fate and ecotoxicity of lanthanides: are they a uniform group beyond chemistry?

    PubMed

    Gonzalez, Veronica; Vignati, Davide A L; Leyval, Corinne; Giamberini, Laure

    2014-10-01

    Lanthanides are a chemically uniform group of metals (La-Lu) that, together with yttrium (Y) and scandium (Sc), form the group of rare earth elements (REEs). Because of their many applications (e.g., agriculture, medicine, motor industry), their global production has increased exponentially in the last decades and their biogeochemical cycles are being disrupted by human uses (e.g., gadolinium anomalies in freshwater and tap water, REEs enrichment of soils as a consequence of agricultural practices). However, ecotoxicological effects and mechanism of action of these elements are still poorly understood. In particular, there is no consensus as to lanthanides showing a coherent and predictable pattern of (eco)toxicity in the same way as their atomic properties. For aquatic organisms, contradictory conclusions on this issue can be found in the bibliography. This review shows that the variable composition of culture media used in ecotoxicology, and the associated differences in lanthanide's speciation, are the most likely cause for such discrepancies. In particular, the formation of insoluble species in some highly complexing media likely leads to changes in the soluble concentration of lanthanide during some tests; with the potential for a generalized underestimation of their toxicity at the present state of knowledge. For terrestrial organisms, suitable studies to establish trends in lanthanides' toxicity are practically nonexistent; with most research focusing on the effects of REE mixtures. Molecular level studies to elucidate the mechanisms of action of lanthanides are essentially limited to La, pointing to the need for further research to identify common mechanisms of action or modes of action across lanthanides. Overall, agreement on the correct procedures to follow to obtain reliable and comparable data for individual lanthanide is the first action to take in order to arrive at a reliable risk assessment for this group of elements in both aquatic and terrestrial systems. PMID:25036616

  1. Rapid transdermal bloodless and reagent-free malaria detection

    NASA Astrophysics Data System (ADS)

    Lukianova-Hleb, Ekaterina Y.; Campbell, Kelly M.; Constantinou, Pamela E.; Braam, Janet; Olson, John S.; Ware, Russell E.; Sullivan, David S.; Lapotko, Dmitri

    2014-02-01

    Successful diagnosis, screening, and elimination of malaria critically depend on rapid and sensitive detection of this dangerous infection, preferably transdermally and without sophisticated reagents or blood drawing. Such diagnostic methods are not currently available. Here we show that the high optical absorbance and nanosize of endogenous heme nanoparticles called hemozoin, a unique component of all blood-stage malaria parasites, generate a transient vapor nanobubble around hemozoin in response to a short and safe near-infrared picosecond laser pulse. The acoustic signals of these malaria-specific nanobubbles provided the first transdermal non-invasive and rapid detection of a malaria infection as low as 0.00034% in animals without using any reagents or drawing blood. These on-demand transient events have no analogs among current malaria markers and probes, can detect and screen malaria in seconds and can be realized as a compact, easy to use, inexpensive and safe field technology.

  2. Liposomes as signal amplification reagents for bioassays in microfluidic channels.

    PubMed

    Locascio, Laurie E; Hong, Jennifer S; Gaitan, Michael

    2002-03-01

    Liposomes with encapsulated carboxyfluorescein were used in an affinity-based assay to provide signal amplification for small-volume fluorescence measurements. Microfluidic channels were fabricated by imprinting in a plastic substrate material, poly(ethylene terephthalate glycol) (PETG), using a silicon template imprinting tool. Streptavidin was linked to the surface through biotinylated-protein for effective immobilization with minimal nonspecific adsorption of the liposome reagent. Lipids derivatized with biotin were incorporated into the liposome membrane to make the liposomes reactive for affinity assays. Specific binding of the liposomes to microchannel walls, dependence of binding on incubation time, and nonspecific adsorption of the liposome reagent were evaluated. The results of a competitive assay employing liposomes in the microchannels are presented. PMID:11891714

  3. Microfluidic synthesis of rigid nanovesicles for hydrophilic reagents delivery.

    PubMed

    Zhang, Lu; Feng, Qiang; Wang, Jiuling; Sun, Jiashu; Shi, Xinghua; Jiang, Xingyu

    2015-03-23

    We present a hollow-structured rigid nanovesicle (RNV) fabricated by a multi-stage microfluidic chip in one step, to effectively entrap various hydrophilic reagents inside, without complicated synthesis, extensive use of emulsifiers and stabilizers, and laborious purification procedures. The RNV contains a hollow water core, a rigid poly (lactic-co-glycolic acid) (PLGA) shell, and an outermost lipid layer. The formation mechanism of the RNV is investigated by dissipative particle dynamics (DPD) simulations. The entrapment efficiency of hydrophilic reagents such as calcein, rhodamine?B and siRNA inside the hollow water core of RNV is ?90?%. In comparison with the combination of free Dox and siRNA, RNV that co-encapsulate siRNA and doxorubicin (Dox) reveals a significantly enhanced anti-tumor effect for a multi-drug resistant tumor model. PMID:25704675

  4. Development of new vaccines and diagnostic reagents against tuberculosis.

    PubMed

    Mustafa, Abu Salim

    2002-09-01

    Tuberculosis (TB) is a major infectious disease problem with one-third of the world population infected, 8 million people developing the active disease and 2 million dying of TB each year. The attenuated Mycobacterium bovis Bacillus Calmette Guerin (BCG) is the only available vaccine against TB. However, the trials conducted in different parts of the world have shown that this vaccine doe not provide consistent protection against TB. The purified protein derivative (PPD) of Mycobacterium tuberculosis is the commonly used reagent for the diagnosis of TB. However, PPD lacks specificity because of the presence of antigens crossreactive with M. bovis BCG and other mycobacteria. The studies to identify M. tuberculosis antigens and epitopes as candidates for new protective vaccines and specific diagnostic reagents against TB have led to the identification and characterization of several major antigens of M. tuberculosis including heat shock proteins (hsp) and secreted antigens present in the culture filtrate (CF) of M. tuberculosis. Some of these antigens have shown promise as new candidate vaccines (hsp60, Ag85 and ESAT-6, etc.) and specific diagnostic reagents (ESAT-6 and CFP10, etc.) for TB. Moreover, in the mouse model of TB, vaccination with DNA-hsp60 has immunotheraputic effects and helps in eradication of persisters. In addition, identification of proper adjuvant and delivery systems has shown the promise to overcome the problem of poor immunogenicity associated with subunit and peptide based vaccines. More recently, the comparison of the genome sequence of M. tuberculosis with M. bovis BCG and other mycobacteria has led to the identification of M. tuberculosis-specific genomic regions. Evaluation of these regions for encoding proteins with immunological reactivity can lead to the identification of additional antigens of M. tuberculosis useful as new vaccines and reagents for specific diagnosis of TB. PMID:12213334

  5. Reagent Selection Methodology for a Novel Explosives Detection Platform

    ScienceCinema

    None

    2012-12-31

    This video describes research being conducted by Dr. Marvin Warner, a research scientist at Pacific Northwest National Laboratory, in the individual pieces of antibodies used to set up a chemical reaction that will give off light just by mixing reagents together with a sample that contains an explosive molecule. This technology would help detect if explosives are present with just the use of a handheld system or container.

  6. A new reagent method for descaling heat-exchanging equipment

    Microsoft Academic Search

    L. A. Luchinina; T. D. Konovalova; F. K. Davlet'yarova

    1986-01-01

    Corrosion and electrochemical studies of metallic materials (steel, St2, 08Kh22N6T, 12KhI8NIOT, copper M3, brass L062~I, aluminum ADI, titanium VT-O) applicable fo~ fabrication of heat-exchanging equipment were made to explore the scope of industrial use of the new reagent method. The tests were carried out on a special setup (Fig. i). The extent of carbonate scale removal and the corrosion rate

  7. Behavior of a chlorinated ethene plume following source-area treatment with Fenton's reagent

    USGS Publications Warehouse

    Chapelle, F.H.; Bradley, P.M.; Casey, C.C.

    2005-01-01

    Monitoring data collected over a 6-year period show that a plume of chlorinated ethene-contaminated ground water has contracted significantly following treatment of the contaminant source area using in situ oxidation. Prior to treatment (1998), concentrations of perchloroethene (PCE) exceeded 4500 ??g/L in a contaminant source area associated with a municipal landfill in Kings Bay, Georgia. The plume emanating from this source area was characterized by vinyl chloride (VC) concentrations exceeding 800 ??g/L. In situ oxidation using Fenton's reagent lowered PCE concentrations in the source area below 100 ??g/L, and PCE concentrations have not rebounded above this level since treatment. In the 6 years following treatment, VC concentrations in the plume have decreased significantly. These concentration declines can be attributed to the movement of Fenton's reagent-treated water downgradient through the system, the cessation of a previously installed pump-and-treat system, and the significant natural attenuation capacity of this anoxic aquifer. While in situ oxidation briefly decreased the abundance and activity of microorganisms in the source area, this activity rebounded in <6 months. Nevertheless, the shift from sulfate-reducing to Fe(III)-reducing conditions induced by Fenton's treatment may have decreased the efficiency of reductive dechlorination in the injection zone. The results of this study indicate that source-area removal actions, particularly when applied to ground water systems that have significant natural attenuation capacity, can be effective in decreasing the areal extent and contaminant concentrations of chlorinated ethene plumes. Copyright ?? 2005 National Ground Water Association.

  8. Gold Coated Lanthanide Phosphate Nanoparticles for Targeted Alpha Generator Radiotherapy

    PubMed Central

    McLaughlin, Mark F.; Woodward, Jonathan; Boll, Rose A.; Wall, Jonathan S.; Rondinone, Adam J.; Kennel, Stephen J.; Mirzadeh, Saed; Robertson, J. David

    2013-01-01

    Targeted radiotherapies maximize cytotoxicty to cancer cells. In vivo ?-generator targeted radiotherapies can deliver multiple ? particles to a receptor site dramatically amplifying the radiation dose delivered to the target. The major challenge with ?-generator radiotherapies is that traditional chelating moieties are unable to sequester the radioactive daughters in the bioconjugate which is critical to minimize toxicity to healthy, non-target tissue. The recoil energy of the 225Ac daughters following ? decay will sever any metal-ligand bond used to form the bioconjugate. This work demonstrates that an engineered multilayered nanoparticle-antibody conjugate can deliver multiple ? radiations and contain the decay daughters of 225Ac while targeting biologically relevant receptors in a female BALB/c mouse model. These multi-shell nanoparticles combine the radiation resistance of lanthanide phosphate to contain 225Ac and its radioactive decay daughters, the magnetic properties of gadolinium phosphate for easy separation, and established gold chemistry for attachment of targeting moieties. PMID:23349921

  9. Supramolecular luminescent lanthanide dimers for fluoride sequestering and sensing.

    PubMed

    Liu, Tao; Nonat, Aline; Beyler, Maryline; Regueiro-Figueroa, Martín; Nchimi Nono, Katia; Jeannin, Olivier; Camerel, Franck; Debaene, François; Cianférani-Sanglier, Sarah; Tripier, Raphaël; Platas-Iglesias, Carlos; Charbonnière, Loïc J

    2014-07-01

    Lanthanide complexes (Ln=Eu, Tb, and Yb) that are based on a C2 -symmetric cyclen scaffold were prepared and characterized. The addition of fluoride anions to aqueous solutions of the complexes resulted in the formation of dinuclear supramolecular compounds in which the anion is confined into the cavity that is formed by the two complexes. The supramolecular assembly process was monitored by UV/Vis absorption, luminescence, and NMR spectroscopy and high-resolution mass spectrometry. The X-ray crystal structure of the europium dimer revealed that the architecture of the scaffold is stabilized by synergistic effects of the Eu?F?Eu bridging motive, ??stacking interactions, and a four-component hydrogen-bonding network, which control the assembly of the two [EuL] entities around the fluoride ion. The strong association in water allowed for the luminescence sensing of fluoride down to a detection limit of 24?nM. PMID:24909695

  10. Tetraanionic biphenyl lanthanide complexes as single-molecule magnets.

    PubMed

    Huang, Wenliang; Le Roy, Jennifer J; Khan, Saeed I; Ungur, Liviu; Murugesu, Muralee; Diaconescu, Paula L

    2015-03-01

    Inverse sandwich biphenyl complexes [(NN(TBS))Ln]2(?-biphenyl)[K(solvent)]2 [NN(TBS) = 1,1'-fc(NSi(t)BuMe2)2; Ln = Gd, Dy, Er; solvent = Et2O, toluene; 18-crown-6], containing a quadruply reduced biphenyl ligand, were synthesized and their magnetic properties measured. One of the dysprosium biphenyl complexes was found to exhibit antiferromagnetic coupling and single-molecule-magnet behavior with Ueff of 34 K under zero applied field. The solvent coordinated to potassium affected drastically the nature of the magnetic interaction, with the other dysprosium complex showing ferromagnetic coupling. Ab initio calculations were performed to understand the nature of magnetic coupling between the two lanthanide ions bridged by the anionic arene ligand and the origin of single-molecule-magnet behavior. PMID:25695369

  11. Gold Coated Lanthanide Phosphate Nanoparticles for Targeted Alpha Generator Radiotherapy

    SciTech Connect

    McLaughlin, Mark F [ORNL; Woodward, Jonathan [ORNL; Boll, Rose Ann [ORNL; Wall, Jonathan [University of Tennessee, Knoxville (UTK); Rondinone, Adam Justin [ORNL; Kennel, Steve J [ORNL; Mirzadeh, Saed [ORNL; Robertson, David J. [University of Missouri

    2013-01-01

    Targeted radiotherapies maximize cytotoxicty to cancer cells. In vivo generators such as 225Ac, which emits four particles in its decay chain, can significantly amplify the radiation dose delivered to the target site. However, renal dose from unbound 213Bi escaping during the decay process limits the dose of 225Ac that can be administered. Traditional chelating moieties are unable to sequester the radioactive daughters because of the high recoil energy from alpha particle emission. To counter this, we demonstrate that an engineered multilayered nanoparticle-antibody conjugate can both deliver radiation and contain the decay daughters of the in vivo -generator 225Ac while targeting biologically relevant receptors. These multi-shell nanoparticles combine the radiation resistance of crystalline lanthanide phosphate to encapsulate and contain 225Ac and its radioactive decay daughters, the magnetic properties of gadolinium phosphate for easy separation, and established surface chemistry of gold for attachment of nanoparticles to targeting antibodies.

  12. Solid-water detoxifying reagents for chemical and biological agents

    DOEpatents

    Hoffman, Dennis M. (Livermore, CA); Chiu, Ing Lap (Castro Valley, CA)

    2006-04-18

    Formation of solid-water detoxifying reagents for chemical and biological agents. Solutions of detoxifying reagent for chemical and biological agents are coated using small quantities of hydrophobic nanoparticles by vigorous agitation or by aerosolization of the solution in the presence of the hydrophobic nanoparticles to form a solid powder. For example, when hydrophobic fumed silica particles are shaken in the presence of IN oxone solution in approximately a 95:5-weight ratio, a dry powder results. The hydrophobic silica forms a porous coating of insoluble fine particles around the solution. Since the chemical or biological agent tends to be hydrophobic on contact with the weakly encapsulated detoxifying solution, the porous coating breaks down and the detoxifying reagent is delivered directly to the chemical or biological agent for maximum concentration at the point of need. The solid-water (coated) detoxifying solutions can be blown into contaminated ventilation ducting or other difficult to reach sites for detoxification of pools of chemical or biological agent. Once the agent has been detoxified, it can be removed by flushing the area with air or other techniques.

  13. Sulfhydryl reagents and energy-linked reactions in monocot thylakoids.

    PubMed

    Cohen, W S; Baxter, D R

    1990-07-01

    Monofunctional maleimides have been used to covalently modify the coupling factor protein of monocot thylakoid membranes. As with dicot thylakoids, incubation of the monocot thylakoids with maleimides in the light but not in the dark results in inhibition of both ATP synthesis and hydrolysis. In the dark, sites on the gamma and epsilon subunits of maize Zea mays coupling factor 1 are modified after incubation of maize mesophyll thylakoids with the fluorescent maleimide N-(anilinonaphthyl-4) maleimide. A light accessible site localized solely to the gamma subunit has also been demonstrated. In contrast to the case with dicot thylakoids (spinach [Spinacia oleracea] and pea [Pisum sativum]) treatment of monocot thylakoids (maize, barley [Hordeum vulgare], crabgrass [Digitaria sanguinalis]) with bifunctional maleimides or thiol oxidants in the light does not result in functional uncoupling, i.e the bifunctional reagents act more like energy transfer inhibitors. The lack of functional uncoupling could be due either to a failure of the reagents to cross-link key sulfhydryl residues in the gamma subunit or to the continued ability of the gamma subunit to gate proton movements through the chloroplast coupling factor complex even though its conformation has been altered by sulfhydryl reagents. PMID:16667548

  14. UV Decontamination of MDA Reagents for Single Cell Genomics

    SciTech Connect

    Lee, Janey; Tighe, Damon; Sczyrba, Alexander; Malmatrom, Rex; Clingenpeel, Scott; Malfatti, Stephanie; Rinke, Christian; Wang, Zhong; Stepanauskas, Ramunas; Cheng, Jan-Fang; Woyke, Tanja

    2011-03-18

    Single cell genomics, the amplification and sequencing of genomes from single cells, can provide a glimpse into the genetic make-up and thus life style of the vast majority of uncultured microbial cells, making it an immensely powerful and increasingly popular tool. This is accomplished by use of multiple displacement amplification (MDA), which can generate billions of copies of a single bacterial genome producing microgram-range DNA required for shotgun sequencing. Here, we address a key challenge inherent to this approach and propose a solution for the improved recovery of single cell genomes. While DNA-free reagents for the amplification of a single cell genome are a prerequisite for successful single cell sequencing and analysis, DNA contamination has been detected in various reagents, which poses a considerable challenge. Our study demonstrates the effect of UV irradiation in efficient elimination of exogenous contaminant DNA found in MDA reagents, while maintaining Phi29 activity. Consequently, we also find that increased UV exposure to Phi29 does not adversely affect genome coverage of MDA amplified single cells. While additional challenges in single cell genomics remain to be resolved, the proposed methodology is relatively quick and simple and we believe that its application will be of high value for future single cell sequencing projects.

  15. Facile sonochemical synthesis and photoluminescent properties of lanthanide orthophosphate nanoparticles

    SciTech Connect

    Yu Cuicui; Yu Min [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Department of Chemistry, Northeast Normal University, Changchun 130024 (China); Li Chunxia; Liu Xiaoming; Yang Jun; Yang Piaoping [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Lin Jun [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)], E-mail: jlin@ciac.jl.cn

    2009-02-15

    Uniform lanthanide orthophosphate LnPO{sub 4} (Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho) nanoparticles have been systematically synthesized via a facile, fast, efficient ultrasonic irradiation of inorganic salt aqueous solution under ambient conditions without any surfactant or template. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), photoluminescence (PL) spectra as well as kinetic decays were employed to characterize the samples. The SEM and the TEM images show that the hexagonal structured lanthanide orthophosphate LnPO{sub 4} (Ln=La, Ce, Pr, Nd, Sm, Eu, Gd) products have nanorod bundles morphology, while the tetragonal LnPO{sub 4} (Ln=Tb, Dy, Ho) samples prepared under the same experimental conditions are composed of nanoparticles. HRTEM micrographs and SAED results prove that these nanostructures are polycrystalline in nature. The possible formation mechanism for LnPO{sub 4} (Ln=La-Gd) nanorod bundles is proposed. Eu{sup 3+}-doped LaPO{sub 4} and Tb{sup 3+}-doped CePO{sub 4} samples were also prepared by using the same synthetic process, which exhibit an orange-red (Eu{sup 3+}:{sup 5}D{sub 0}-{sup 7}F{sub 1,2,3,4}) and green (Tb{sup 3+}, {sup 5}D{sub 4}-{sup 7}F{sub 3,4,5,6}) emission, respectively. - Graphical Abstract: Hexagonal LnPO{sub 4} (Ln=La, Ce, Pr, Nd, Sm, Eu, Gd) and tetragonal LnPO{sub 4} (Ln=Tb, Dy, Ho) nanoparticles have been synthesized by a simple and facile sonochemical method.

  16. Calculating Expectation Shift

    E-print Network

    Frey, Daniel

    2011-01-01

    This paper concerns the problem of calculating expectation shift due to variability which tends to occur whenever the function of a random variable is nonlinear and especially tends to occur in the neighborhood of a local ...

  17. Isotope Shift in Magnesium

    Microsoft Academic Search

    L. G. Mundie; K. W. Meissner

    1944-01-01

    The previous investigations concerning the isotope shift of magnesium have been repeated and extended by means of an improved atomic beam source and a Perot-Fabry interferometer. The values of Meissner have been checked to within experimental error in most cases. In addition, several new lines have been resolved, and their isotope shifts determined. The 31P-m1D series has been resolved from

  18. Inactivation of Viable Ascaris Eggs by Reagents during Enumeration

    PubMed Central

    Nelson, Kara L.; Darby, Jeannie L.

    2001-01-01

    Various reagents commonly used to enumerate viable helminth eggs from wastewater and sludge were evaluated for their potential to inactivate Ascaris eggs under typical laboratory conditions. Two methods were used to enumerate indigenous Ascaris eggs from sludge samples. All steps in the methods were the same except that in method I a phase extraction step with acid-alcohol (35% ethanol in 0.1 N H2SO4) and diethyl ether was used whereas in method II the extraction step was avoided by pouring the sample through a 38-?m-mesh stainless steel sieve that retained the eggs. The concentration of eggs and their viability were lower in the samples processed by method I than in the samples processed by method II by an average of 48 and 70%, respectively. A second set of experiments was performed using pure solutions of Ascaris suum eggs to elucidate the effect of the individual reagents and relevant combination of reagents on the eggs. The percentages of viable eggs in samples treated with acid-alcohol alone and in combination with diethyl ether or ethyl acetate were 52, 27, and 4%, respectively, whereas in the rest of the samples the viability was about 80%. Neither the acid nor the diethyl ether alone caused any decrease in egg viability. Thus, the observed inactivation was attributed primarily to the 35% ethanol content of the acid-alcohol solution. Inactivation of the eggs was prevented by limiting the direct exposure to the extraction reagents to 30 min and diluting the residual concentration of acid-alcohol in the sample by a factor of 100 before incubation. Also, the viability of the eggs was maintained if the acid-alcohol solution was replaced with an acetoacetic buffer. None of the reagents used for the flotation step of the sample cleaning procedure (ZnSO4, MgSO4, and NaCl) or during incubation (0.1 N H2SO4 and 0.5% formalin) inactivated the Ascaris eggs under the conditions studied. PMID:11722892

  19. [An evaluation of the China-made HIV antibody test reagents].

    PubMed

    Zheng, X W; Zhu, D

    1990-06-01

    This paper reports the results of the evaluation of the China-made HIV antibody screening test reagents, including the IF and IE reagents prepared by the Institute of Virology, CAPM, the ELISA reagent prepared by the Shanghai Institute of Biological Products. Based on the results, the sensitivities of the IF and IE are from 91.2% to 96.9%; the specificities, from 94.6% to 97.3%. Due to the low HIV prevalence in China, the predictive values of negative of these reagents are up to 100%; but the predictive values of positive are very low. It is suggested that these reagents can be used for HIV antibody screen testing in China. The package of some reagents should be improved, the price of some reagents should be decreased. PMID:2390778

  20. Methods and apparatuses for reagent delivery, reactive barrier formation, and pest control

    DOEpatents

    Gilmore, Tyler [Pasco, WA; Kaplan, Daniel I [Aiken, SC; Last, George [Richland, WA

    2002-07-09

    A reagent delivery method includes positioning reagent delivery tubes in contact with soil. The tubes can include a wall that is permeable to a soil-modifying reagent. The method further includes supplying the reagent in the tubes, diffusing the reagent through the permeable wall and into the soil, and chemically modifying a selected component of the soil using the reagent. The tubes can be in subsurface contact with soil, including groundwater, and can be placed with directional drilling equipment independent of groundwater well casings. The soil-modifying reagent includes a variety of gases, liquids, colloids, and adsorbents that may be reactive or non-reactive with soil components. The method may be used inter alia to form reactive barriers, control pests, and enhance soil nutrients for microbes and plants.