Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Tin Compounds”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 523 records · Page 29Linked to original sources
PubMed1996

Pilot study on the contamination of drinking water by organotin compounds from PVC materials.

Raw and treated water samples and tap water samples from four to six houses located on distribution lines where PVC pipe/tubing had been recently installed were collected in five Canadian municipalities for the analysis of organotin compounds. After derivatisation with sodium tetraethylborate the ethylated organotin compounds were extracted with hexane and analysed by gas chromatography-microwave induced plasma atomic emission spectrometry using a wavelength (326.234 nm) specific for tin. Organotin compounds, mainly methyltin and dimethyltin at concentrations ranging respectively from 0.5 to 257 ng Sn/L and from 0.5 to 6.5 ng Sn/L, were detected in samples from ten of the twenty-two houses. No organotin compounds were detected in raw water or treated water leaving the treatment plant, indicating that the organotin compounds were leaching into the water from some component of the distribution system.

Borates↗
PubMed1999

Characterization and preliminary evaluation of ester-modified technetium-99m SNS/S mixed ligand complexes as potential brain perfusion agents.

Two novel [99mTc](SNS/S) mixed ligand complexes carrying a pendant ester function on the monothiolate coligand were synthesized. The corresponding oxorhenium and [99gTc]oxotechnetium complexes prepared at the macroscopic level and chemically characterized were used for structure assignment of [99mTc](SNS/S) complexes prepared at the nanomolar level. Enzymatic hydrolysis of the pendant ester group of [99mTc](SNS/S) mixed ligand complexes by esterase was investigated in vitro and compared with that of the ethyl cysteinate dimer, [99mTc]ECD. Preliminary biodistribution data in mice shows that the complexes are lipophilic and exhibit significant initial uptake in rodent brain.

Animals↗
PubMed2005

Metal-assembling dendrimers with a triarylamine core and their application to a dye-sensitized solar cell.

A series of charge-separable and hole-transporting phenylazomethine dendrimers with a triarylamine core are prepared and evaluated for use as a charge separator in dye-sensitized solar cells (DSSCs). Triphenylamine with dendric phenylazomethine (TPA-DPA) is prepared by synthesizing up to five generations of dendrons using a convergent method. The resultant dendrimer has a rigid sphere structure similar to globular protein, with a hydrodynamic radius of 2.43 nm. Electrochemical oxidation of the TPA core reveals that the dendron units in the dendrimer have 0.35 of the attenuation factor (beta) in the electron transfer. Complexation of TPA-DPA with SnCl2 proceeds in stepwise fashion from the core to the terminal imine following the basicity gradient among imine groups in each dendron shell. DSSCs prepared by casting these dendrimers onto dye-sensitized TiO2 film exhibited a higher open-circuit voltage than the bare film through the suppression of back electron transfer. The generational growth of dendrons increases the radius of the dendrimer, resulting in a stronger association with I3- and higher open-circuit voltage with an increasing number of generations. Complexation with SnCl2 reduces the resistance of TPA-DPA and improves the fill factor. The energy conversion efficiency of the DSSC prepared using fifth-generation TPA-DPA is 21% higher than that for the bare film and, when complexed with SnCl2, provides a 34% improvement.

Aniline Compounds↗
PubMed2002

A short synthesis of (+)-narciclasine via a strategy derived from stereocontrolled epoxide formation and SnCl(4)-catalyzed arene-epoxide coupling.

A facile construction of the typical framework of narcissus alkaloids has been realized by virtue of the development of a practical route involving stereocontrolled epoxide formation and SnCl(4)-catalyzed arene-epoxide coupling. To achieve this goal, it proved to be necessary to devise a strategy that would enable chemical transformations to install an epoxy moiety in a congested environment. The successful preparation of a hindered epoxide from O-isopropylidene-protected 4-aminocyclohexenol required three steps consisting principally of controlled bromohydration and base-promoted closure and N-alkylation. It was found that a catalytic amount of SnCl(4) not only maintained the catalytic cycle but also effected clean arylation to form a fused BC ring system. Several tactics that ultimately proved to be unsatisfactory are also discussed in an effort to set important boundary limits on arene-epoxide coupling. The requisite enantiopure 4-aminocyclohexenol was available via an asymmetric cycloaddition of diene to camphor-based chloronitroso. The total synthesis of (+)-narciclasine was realized in nine steps with an overall yield of 19%.

Alkaloids↗
PubMed1994

Discordant uptake of Tc-99m DTPA-galactosyl human serum albumin and Tc-99m Sn colloid in a patient with severe acute hepatitis.

A patient with recently diagnosed severe acute hepatitis underwent serial liver scintigraphy with Tc-99m Sn colloid and Tc-99m DTPA-galactosyl human serum albumin. In initial studies, radionuclide distribution on Tc-99m DTPA-galactosyl human serum albumin scintigraphy was completely discrepant to that on Tc-99m Sn colloid scintigraphy. In a follow-up study 1 month later, the distribution of both radionuclides in the liver appeared relatively homogeneous. The uptake of Tc-99m DTPA-galactosyl human serum albumin and Tc-99m Sn colloid reflects the function of hepatocytes and Kupffer cells, respectively. Both kinds of scintigraphic study may be helpful to assess histopathologic change of different hepatic tissue architectures.

Acute Disease↗
PubMed2004

Comparative chemistry of isolable divalent compounds of silicon, germanium, and tin.

Recent studies of the synthesis, structures, spectroscopic properties, and reactions of a series of isolable metallylenes (R2E:, E = Si (1), Ge (2), and Sn (3); R2 = 1,1,4,4-tetrakis(trimethylsilyl)butane-1,4-diyl) are summarized. Because these group-14 metallylenes bear the same helmet-like ligand, a straightforward discussion of the element-dependence of the intrinsic properties of the group-14 element divalent compounds is possible. All these metallylenes were monomeric both in solution and in the solid state, indicating the effective steric protection by the ligand against dimerization. A small sigma-pi conjugation between C-Si(substituent) sigma orbitals and the vacant npz orbitals of divalent atoms in R2E: exists and the extent decreases in the order E = Si > Ge > Sn, as evidenced by UV-vis and NMR spectroscopies and X-ray crystallography. However, the extent of the sigma-pi conjugation in metallylenes 1-3 was much smaller than the electron-donating effects of neighboring nitrogen atoms in known stable cyclic diamino-substituted metallylenes, and hence metallylenes 1-3 are regarded as the least electronically perturbed. Comparative studies of the unique reactions among these metallylenes are also discussed.

Butanes↗
PubMed2006

Studies on photodegradation of two commercial dyes in aqueous phase using different photocatalysts.

The present study involves the photocatalytic degradation of Methyl Orange (MO) and Rhodamine 6G (R6G), employing heterogeneous photocatalytic process. Photocatalytic activity of various semiconductors such as titanium dioxide (TiO(2)), zinc oxide (ZnO), stannic oxide (SnO(2)), zinc sulphide (ZnS) and cadmium sulphide (CdS) has been investigated. An attempt has been made to study the effect of process parameters viz., amount of catalyst, concentration of dye and pH on photocatalytic degradation of MO and R6G. The experiments were carried out by irradiating the aqueous solutions of dyes containing photocatalysts with UV and solar light. The rate of decolorization was estimated from residual concentration spectrophotometrically. Similar experiments were carried out by varying pH (2-10), amount of catalyst (0.25-2.0g/l) and initial concentration of dye (5-200mg/l). The experimental results indicated that the maximum decolorization (more than 90%) of dyes occurred with ZnO catalyst and at basic pH and the maximum adsorption of MO was noticed at pH 4 and of R6G at pH 10. The percentage reduction of MO and R6G was estimated under UV/solar system and it was found that COD reduction takes place at a faster rate under solar light as compared to UV light. In case of R6G, highest decolorizing efficiency was achieved with lower dose of catalyst (0.5g/l) than MO (1g/l) under similar conditions. The performance of photocatalytic system employing ZnO/solar light was observed to be better than ZnO/UV system.

Adsorption↗
PubMed2006

Characterization of proton transport across a waveguide-supported lipid bilayer.

Cellular energy transduction processes are often driven by transmembrane ion gradients, and numerous artificial biomembrane systems have been developed that allow for chemically or light-induced charge transport into/out of liposomes. Liposomal architectures, however, are not readily interfaced to a solid-state transducer. Formation of an ion gradient across a planar-supported membrane, "wired" to a substrate electrode, may ultimately allow utilization of the potential energy to drive other electrochemical processes. Described here is a novel conductive polymer/planar waveguide assembly that provides for highly sensitive transduction of proton transport across a planar-supported lipid bilayer (PSLB). A quinone proton shuttle is embedded in the PSLB, which is coupled to the planar optical waveguide electrode through a pH-sensitive, self-assembled conductive polymer film. Interfacial potential and absorbance changes in the conductive polymer film provide for sensitive characterization of transmembrane proton transport. The general and flexible nature of this architecture makes it adaptable to many different types of transmembrane transport chemistries, particularly light-activated systems.

Acrylic Resins↗
PubMed2006

SnO2 nanoparticle-functionalized boron nitride nanotubes.

Boron nitride nanotubes (BNNTs) were synthesized by a carbon-free chemical vapor deposition method using boron and metal oxide as reactants. Then SnO(2) nanoparticles were functionalized on them via a simple wet chemistry method. Detailed transmission electron microscopy (TEM) observations reveal that SnO(2) nanoparticles may cover the tube surface or be encapsulated in tube channels. The lattice distances of both BNNT and SnO(2) have been changed due to the strong interactions between them. The band gap energy of SnO(2) particles is found enlarged due to the size effect and interaction with BNNTs.

Boron Compounds↗
PubMed1996

99mTc-dextran-antibody conjugates. Labelling procedures.

Dextran forms stable chelates with 99mTc, a radionuclide with ideal properties for planar scintigraphic and tomographic imaging. This study investigates some of the factors of importance to the formation of 99mTc-dextran. The complex was used for the technetium labelling of a monoclonal antibody. Two radiolabelling methods were studied: direct dextran labelling with the reductant dissolved in HCI and labelling via a weak 'transfer' chelator (tartaric acid) with the reductant dissolved in ethanol. Different conditions during the labelling reaction were studied. Finally, dextran was coupled to a monoclonal anticytokeratin antibody and the conjugate was subsequently radiolabelled with 99mTc. Gel filtration (GFR) and thin layer chromatography (TLC) were compared as methods for estimation of the labelling efficiency. When using 10-500 microM of ligand, 5-100 microM SnCl2 with 10-500 MBq of technetium at pH 7 incubated for 10-15 min, the radiolabelling seemed optimal (70-75% labelling efficiency). It was found that 100 microM tartaric acid used as a weak intermediate chelator with SnCl2 dissolved in ethanol improved the reproducibility of the labelling. The labelling efficiency was not affected by either the presence of oxygen or the addition of an oxygen scavenger during the labelling incubation. In general, TLC showed higher labelling efficiencies than GFR, indicating inadequate separation of the different moieties.

Antibodies, Monoclonal↗
PubMed1996

Speciation of mercury, platinum and tin - focus of research and future developments.

A discussion about the elements mercury, platinum and tin and their organometallic compounds, with special attention to important aspects like anthropogenic emissions, use in industry, agriculture and medicine, toxicities, biogeochemical cycles, highlights the necessity of speciation analysis. Methods frequently used to speciate mercury, platinum and tin compounds in different matrices are summarized. Future trends are indicated in order to give an impression about the importance of metal speciation and its increasing impact on some key disciplines.

Journal Article↗