bluuebunny/crossref_metadata_2025_split huggingface dataset:
Elevated tri(n‐butyl)tin concentrations in shellfish and sediments from Suva Harbour, Fiji
Authors: Stewart C , De Mora S J 
Published: January 2005

AbstractTri(n‐butyl)tin (TBT) concentrations were determined in sediments and selected shellfish from Suva Harbour, Fiji. Sediments in the immediate vicinity of foreshore slipways and boatyards were exceedingly contaminated, with a maximum observed level of 38μ g−1 TBT‐Sn. Concentrations were much lower in surficial sediments from commercial docks and yacht mooring areas, namely 16–83 ng g−1 TBT‐Sn. Mangrove oysters (Crassostrea mordax), gastropods (Thais mancinella), and bivalves (Anadara scapha) were found to have accumulated TBT. Concentrations as high as 3180 ng g−1 TBT‐Sn were found in mangrove oysters. With respect to the mangrove oyster, its widespread distribution, abundance and proclivity to accumulate TBT suggest that it is likely to be the best bioindicator species of TBT contamination in Fijian coastal waters.
Spermatocyte chromosome alterations in truncatella subcylindrica (L., 1767) (Mollusca, Mesogastropoda) following exposure to dibutyltin(IV) and tributyltin(IV) chlorides
Authors: Vitturi R , Mansueto C , Catalano E , Pellerito L , Girasolo M A 
Published: January 2005

AbstractIn order to analyze chromosomes for possible numerical and structural alterations in response to exposure to organotin(IV) compounds, gastropod Truncatella subcylindrica specimens were treated with dibutyltin(IV) and tributyltin(IV) chloride solutions with different exposure times.Experimental evidence suggests that tributyltin(IV) chloride is more toxic to this organism than dibutyltin(IV) dichloride at low concentrations. Furthermore, the toxicity responses to these organotin(IV) derivatives seem to be proportional to both concentration and exposure time.The following structural lesions have been identified by comparative analysis of spermatocyte chromosomes from untreated specimens and specimens treated with organotin(IV) compounds: (1) breakages; (2) bridging; (3) irregular outline; and (4) light areas after staining with acetic orcein. In this respect, dibutyltin(IV) and tributyltin(IV) chlorides seem to have an effect similar to that of colchicine.
The determination of organotin compounds in fruit juices using gas chromatography‐atomic absorption spectrometry
Authors: Forsyth D S , Weber D , Barlow L 
Published: January 2005

AbstractA method for extracting butyl‐, cyclohexyl‐, octyland phenyl‐tin compounds in fruit juices was developed using 0.05% tropolone in 25% pentane/diethyl ether. Methyl derivatives formed by Grignard reaction were quantified by gas chromatography‐atomic absorption spectrometry. Several fruit juices contained low ng cm−3 levels of butyl‐ and octyl‐tins. Gas chromatography‐mass spectrometry, used for the confirmation of the butyl‐ and octyl‐tins, also detected phenyl‐ and cyclohexyl‐tin compounds at levels below the GC AA detection limits (0.03–0.05 ng Sn cm−3).
Synthesis and spectroscopic characterization of dicyclohexyltin derivatives of dipeptides, and in vitro effects against MDA‐MB 231 breast cancer cells: Crystal structures of dicyclohexyltin glycylglycinate and glycylalaninate
Authors: Huber Friedo , Vornefeld Michael , Preut Hans , von Angerer Erwin , Ruisi Giuseppe 
Published: January 2005

AbstractDicyclohexyltin derivatives Cy2SnL (Cy = cyclohexyl) of the dipeptides H2L, glycylglycine, glycylalanine, alanylglycine, glycylvaline, glycylmethionine, glycylphenylalanine and glycyltyrosine, have been obtained by neutralization of Cy2SnO and H2L.The crystal structures of Cy2SnL (L = glycylglycinate, glycylalaninate) have been determined by single X‐ray diffraction. Tin in each case has a distorted trigonal bipyramidal environment with the dipeptide acting as a tridentate NNO‐ligand. From IR‐data, and in some cases from 119Sn Mössbauer and 119Sn NMR data, analogous molecular structures are inferred for the other compounds Cy2SnL. Spectroscopic data indicate that the solid‐state structures are retained in organic solvents.In vitrotests showed Cy2SnL (H2L = glycylglycine, glycylalanine, alanylglycine, glycylphenylalanine, glycyltyrosine) to exhibit high cytotoxicity against MDA/MB 231 breast cancer cells, while Me2SnL (L = glycylalaninate, glycyltyrosinate, glycyltryptophanate), and R2Snglycylglycinate (Rn‐Bu, Ph) proved to be much less active.
Organometallic Langmuir‐Blodgett films for electronics and photonics
Authors: Nalwa Hari Singh , Kakuta Atsushi 
Published: January 2005

AbstractThis review provides a brief introduction to the Langmuir‐Blodgett (LB) technique and to the utilization of ultrathin films in the fields of electronics and optics. The electrical and nonlinear optical properties of the Langmuir‐Blodgett monolayer and multilayers of organoruthenium complexes, ferrocene derivatives, metal(4,5‐dimercapto‐1, 3‐dithiol‐2‐dithiolene)2 complexes, metallophthalocyanines, metalloporphyrins, metal(dibenzotetra‐aza[14]annulene)s and siloxane polymers are presented. Possible applications of organometallic LB films in sensors, electroluminescence and electrochromic devices, optical switches, solar cells, infrared detectors and harmonic generators are discussed.
Synthesis, characterization and in vitro antitumour activity of diorganotin bisxanthates [R2Sn(S2COR′)2] (R=Me, Et, nBu, Ph; R′=Et, iPr, Hex) and crystal structure of bis(O‐ethyldithiocarbonato)diphenyltin(IV)
Authors: Donoghue Neil , Tiekink Edward R. T. , Webster Lorraine 
Published: January 2005

AbstractA series of diorganotin bisxanthate compounds, [R2Sn(S2COR′)2] (R=Me, Et, nBu, tBu, and Ph; R′Et, iPr and cHex) have been prepared and characterized by spectroscopic methods (IR, NMR and FAB MS). The xanthate ligands chelate the R2Sn moieties forming disparate Sn–S bonds leading to skew‐trapezoidal biypramidal tin atom geometries. The crystal structure of a representative compound, [Ph2Sn(S2COEt)2], confirms the spectroscopic results and shows the tin atom to be coordinated by two asymmetrically chelating xanthate ligands [Sn–S(1) 2.486(1), Sn–S(2) 3.052(1) Å and Sn–S(3) 2.484(1), Sn–S(4) 3.220(1) Å] with the two phenyl substituents lying over the weaker Sn–S interactions so that C–Sn–C is 126.5(1)∘. Crystal data for [Ph2Sn(S2COEt)2]: monoclinic space group P21/n: a=9.645(1), b=23.723(3), c=9.798(2) Å, ß=100.23(1)∘, V=2206.2 Å3, Z=4; 2708 data refined to final R 0.023. A selection of these compounds has been evaluated for activity against the L1210 mouse leukaemia cell line.
Organobismuth(III) and organobismuth(V) carboxylates and their evaluation as paint driers
Authors: Ali Mushtaq , McWhinnie William R 
Published: January 2005

AbstractA range of bismuth and organobismuth carboxylates has been prepared e.g. Bi(carboxylate)3; PhBi(carboxylate′)2; and Ph3Bi(carboxylate″)2 where carboxylate=octanoate, i.e. 5‐ethylhexanoate; carboxylate′=acetate and monomaleate; carboxylate″=acetate, propionate, benzoate, 5‐ethylhexanoate, and 0.5 oxalate. A combination of IR (solid) and NMR (solution) studies suggests that in the case of the bismuth(V) compounds the carboxylates may be inequivalent in the crystalline forms but equivalent in solution. The compounds have been tested as driers in two paint formulations, Synolac 50W (linseed‐based) and Sorbal P470 (linoleic‐rich). Although initially promising results were obtained for Synolac 50W, the shelf life of the bismuth driers was poor. With Sorbal P470, bismuth driers were inferior to established formulations. However, a combination of Bi(OOCH7H15)3 with tris(diethyldithiocarbamato)‐bismuth(III) out‐performed established driers.
Matrix effects in the determination of butyltin compounds in environmental samples by GC AA after hydride generation
Authors: Quevauviller Ph , Martin F , Belin C , Donard O F X 
Published: January 2005

AbstractExperiments for the determination of mono‐, di and tri‐butyltin (MBT, DBT and TBT) by hydride generation/gas chromatography/atomic absorption spectrometry in various matrices (sediment, suspended matter, mussel, algae and water) have revealed that poor butyltin recoveries are obtained in sediments displaying high sulphur and hydrocarbon contents; very poor recoveries were also observed for TBT in sediments with high chlorophyll pigment contents as well as in algal samples. It was however not clear whether the hydride generatin was inhibited by these infering compounds, as was previously assumed in the case of hydrocarbons, or whether interferences affected the atomization rate. Further studies were performed to solve this problem in order to validate this method in the case of analyses of, for example, oil‐contaminated sediment and algae. This paper presents the results obtained. It is concluded here that the poor recoveries were due to an inhibition of hydride generation rather than to interference at the atomization stage.
Antifertility and biocidal activities of organometallics of silicon, germanium, titanium and zirconium derived from 2‐acetylthiophene thiosemicarbazone
Authors: Singh Devendra , Kumari Anita , Singh R V , Mehta S M , Gupta I J , Singh K 
Published: January 2005

AbstractA comparative biochemical study of four Group IV element compounds with specific sulphur‐containing organic substrates has been carried out and discussed. The structural characterizations of these organometallics, viz. Me2SiLCl, Me2SiL2, Me3SiL, Ph2SiLCl, Ph2SiL2, Ph3SiL, Ph3GeL, Cp2TiLCl, Cp2TiL2, Cp2ZrLCl and Cp2ZrL2 (where LH2‐acetylthiophene thiosemicarbazone) had been deduced on the basis of various physico‐chemical and instrumental techniques, viz., IR, UV, 1H NMR, 13C NMR AND 29SI NMR spectral studies. All the organometallics and the parent thiomine have been screened against a number of microbes and their sterilizing power in male mice tested. The results of these biocidal studies show that the organosilicon(IV) and organogermanium(IV) compounds are more active than the organotitanium(IV) and organozirconium(IV) derivatives. An attempt has also been made to correlate the structural aspects of the molecule with its biological activity.
Effects of tributyltin(IV) chloride exposure on early embryonic stages of Ciona intestinalis: In vivo and ultrastructural investigations
Authors: Mansueto C , Gianguzza M , Dolcemascolo G , Pellerito L 
Published: January 2005

AbstractThe effects of tributyltin(IV) chloride (TBT chloride) solutions on ascidian embryos of Ciona intestinalis have been tested at different stages of development. It has been observed, in vivo, that TBT chooride inhibited cleavage of fertilized eggs and of embryo blastomeres giving rise to cellular masses that are not delimited by plasma membrane. Electron‐dense precipitates of TBT chloride, probably as inorganic tin, have been observed by transmission electron microscopy in the egg cytoplasm of cellular masses.The same type of precipitate was present also inside the mitochondria, whose structure appeared to be highly modified. These ultrastructure aspects are indicative of a degenerative process of the embroys after incubation in TBT chloride.
The effect of arsenicals on alkaloid production by cell suspension cultures of Catharanthus roseus
Authors: Cullen William R , Hettipathirana Deepthi I 
Published: January 2005

AbstractThe effect of arsenic compounds on indole alkaloid production by cell suspension cultures of Catharanthus roseus was investigated. The analysis of indole alkaloids was achieved by using thermospray liquid chromatography‐mass spectrometry (LC MS) which facilitated the rapid screening of alkaloid composition in cultures treated with different arsenicals at different times in their growth cycle.Treatment with dimethylarsinate (DMA), a non‐selective herbicide, has a drastic inhibitory effect on alkaloid production although it is the least toxic arsenical to growth. Tryptamine, an early precursor in the biosynthesis of indole alkaloids, accumulates in cells treated with DMA, indicating that the initial step of condensation of tryptamine with secologanin is inhibited. Treatment with DMA during the early stationary phase of culture growth enhances the accumulation of some alkaloids, although some, such as catharanthine, are suppressed.The arsenicals arsenate and methylarsonate (MMA) have an inhibitory effect on alkaloid production when applied during the early growth stages. In contrast to MMA and DMA, arsenate has a stimulatory effect on catharanthine production when introduced to the culture during its early stationary phase.Thus the changes in the pattern of alkaloid accumulation on addition of arsenicals are dependent on the arsenic species and its concentration, as well as the time of application. This variable response indicates that each arsenical has a distinct mode of action on the secondary metabolic pathways of C. roseus.
Refractory methylated arsenic compounds in estuarine waters: Tracing back elusive species
Authors: De Bettencourt A. M. , Florêncio M. H. , Duarte M. F. N. , Gomes M. L. R. , Vilas Boas L. F. C. 
Published: January 2005

AbstractWater from the Tagus estuary, Portugal, was concentrated and purified through evaporation, solvent extraction, ion exchange and HPLC, and peaks of refractory arsenicals were detected by difference between total arsenic (GF AA) and hydride‐forming arsenic species (HG QF AA). DCI mass spectra of these fractions presented peaks at m/z 139, 157 and 159; the proportion of m/z 157 and 159 peaks, approx. 3:1, suggested a chlorinated moiety. DCI MS/MS daughter‐ion fragmentation of these peaks seems compatible with dimethylarsenic (cacodylic) acid and structures of the type Me2As(O)Cl or Me3As(OH)F. The refractory character of these fractions, however, cannot be explained by these structures. Further work with mixtures of halogen and arsenic species injected in the HPLC system showed that fluoride and iodide can shift DMA (dimethylarsenic) and TMAO (trimethylarsine oxide) to shorter retention times but not to Rf values similar to refractory arsenicals. These latter are attained by mixtures of sodium chloride + arsenobetaine, and sodium fluoride and chloride + arsenocholine. We suggest that peaks at m/z 139 and 157 correspond to fragments of a heavier refractory molecule mainly formed by halogenated betaines including chloroarsenobetaine and chloro‐ and fluoro‐arsenocholine.
A study of trialkyltin β‐aryl‐β‐triphenylgermyl propionates
Authors: Qing‐Lan Xie , Li‐Juan Sun , Hua Liu , Ru‐Ji Wang , Hong‐Gen Wang 
Published: January 2005

AbstractTwenty new compounds of the form Ph3GeCHArCH2COOSnR3 (R = n‐Bu, cyclohexyl; Ar = substituted phenyl) have been synthesized. Their structures were characterized by IR and 119Sn and 1H NMR spectroscopy. The compounds are five‐coordinated carboxylate bridged polymers when R = n– Bu; when R = cyclohexyl (Cy) they are four‐coordinate. 119Sn NMR measurements of chemical shift for the two series of compounds have shown that there is a good linear relationship for the chemical shift of 119Sn NMR between the tributyltin and tricyclohexyltin propionates, viz. δ119Sn(Bu3Sn) = 1.0474 δ 119Sn(Cy3Sn) + 95.8076, n = 5, r = 0.993. The structure of one compound was determined by X‐ray diffraction. It exists as a monomeric four‐coordinated species in a distorted tetrahedronal geometry.
Volatile metal and metalloid species in gases from municipal waste deposits
Authors: Hirner Alfred V. , Feldmann Jörg , Goguel Reiner , Rapsomanikis Spyridon , Fischer Ralf , Andreae Meinrat O. 
Published: January 2005

AbstractWe have detected volatile species of silicon, vanadium, arsenic, bromine, tin, antimony, tellurium, iodine, mercury, lead and bismuth in gases released from domestic waste deposits, using inductively coupled argon plasma mass spectrometry (ICP MS). By concurrent aspiration of a multielement standard solution for calibration, the element concentrations in deposit gas are found to be in the range from 0.1 ng m−3 to 10 μg m−3 gas. The global amount of some metal species emitted by this process may be of the order of several tons per year. These results suggest a biogeochemical pathway for the transfer of metals into the atmosphere via volatile species. This process may have significant influence on atmospheric cycling of metals as well as on metal toxicity within ecosystems.
Bioaccumulation and excretion of arsenic compounds by a marine unicellular alga, polyphysa peniculus
Authors: Cullen William R. , Harrison Lionel G. , Li Hao , Hewitt Gary 
Published: January 2005

AbstractPolyphysa peniculus was grown in artificial seawater in the presence of arsenate, arsenite, monomethylarsonate and dimethylarsinic acid. The separation and identification of some of the arsenic species produced in the cells as well as in the growth medium were achieved by using hydride generation–gas chromatography–atomic absorption spectrometry methodology. Arsenite and dimethylarsinate were detected following incubation with arsenate. When the alga was treated with arsenite, dimethylarsinate was the major metabolite in the cells and in the growth medium; trace amounts of monomethylarsonate were also detected in the cells. With monomethylarsonate as a substrate, the metabolite is dimethylarsinate. Polyphysa peniculus did not metabolize dimethylarsinic acid when it was used as a substrate. Significant amounts of more complex arsenic species, such as arsenosungars, were not observed in the cells or medium on the evidence of flow injection–microwave digestion–hydride generation–atomic absorption spectrometry methodology. Transfer of the exposed cells to fresh medium caused release of most cell–associated arsenicals to the surrounding environment.
Amending cultures of selenium‐resistant bacteria with dimethyl selenone
Authors: Zhang Limin , Chasteen Thomas G. 
Published: January 2005

AbstractA possible biological intermediate in the reduction and methylation of selenium oxyanions, dimethyl selenone, was synthesized, and the first experiments involving the amendment of selenium resistant bacterial cultures with this compound are reported. The amount of volatile, reduced selenium‐containing species released from these cultures into the headspace is significantly more than that produced in analogous experiments involving sodium selenate amended cultures. Dimethyl selenone is reduced in the presence of dimethyl sulfide and dimethyl disulfide in a complex growth medium, trypticase soy broth with 0.1% nitrate. This reduction occurs whether or not the reduced sulfur compounds are biologically produced.
Determination of methylmercury in human hair by capillary GC with electron capture detection
Authors: Chiavarini Salvatore , Cremisini Carlo , Ingrao Giovanni , Morabito Roberto 
Published: January 2005

AbstractAn analytical procedure was developed for the determination of methylmercury in human hair using capillary gas chromatography with electron capture detection (GC–ECD). Hair samples are digested in alkaline solution/toluene in an ultrasonic bath at about 50°C. After cooling and treatment with hydrochloric acid (6 mol I−1) and a saturated solution of copper sulphate, the organic phase is extracted with a cysteine solution. Methylmercury is back‐extracted in toluene by adding copper sulphate and potassium bromide and analysed by GC–ECD using a DB17 capillary column. The practical detection limit of the method for methylmercury is 50 ng g−1 using 100 mg of hair sample. Column performances and injection reproducibility have been evaluated. Results on 13 samples of human hair are presented and related to the total mercury concentration. The method, consisting of the optimization of similar analytical procedures through improvements in the various steps, allows for sensitive and reliable quantitation of methylmercury in hair with good precision and accuracy.
On‐Line speciation of mercury and methylmercury in aqueous samples by chromatography‐atomic fluorescence spectrometry after hydride generation
Authors: Ritsema Rob , Donard Olivier F. X. 
Published: January 2005

AbstractA method is described for the determination of picogram amounts of inorganic mercury(II) and methylmercury(II) compounds in seawater. These compounds are first volatilized from the water samples by reduction to mercury (Hg0) and formation of methylmercury hydride (CH3HgH) by means of a sodium borohydride (NaBH4) solution and cryogenically focused onto a chromatographic stationary phase. Both mercury compounds are eluted according their boiling points and are passed through a pyrolysis tube, at 900°C, before entering the atomic flurescence detector. Absolute detection limits (3σ) are 1 and 2 pg for, respectively, inorganic mercury and methylmercury. For seawater analysis, detection limits of 0.1–1.0 ng I−1 can be achieved.
Interlaboratory study for the improvement of tributyltin determination in harbour sediment (rm 424)
Authors: Quevauviller Ph. , Astruc M. , Ebdon L. , Kramer G. N. , Griepink B. 
Published: January 2005

AbstractFollowing two interlaboratory studies on tributyltin species (TBT) in water and TBT‐spiked sediment, the EC Community Bureau of Reference (BCR) (Measurements and Testing Programme) organized in 1992 an interlaboratory study on TBT in a harbour sediment (RM 424) to investigate sources of error possibly occurring in the analysis of a complicated matrix and to attempt to certify this material. The sediment was collected in the Sado Estuary (P), then carefully prepared, and its homogeneity and stability were verified. The low TBT content encountered in this material, and the high level of interferences, created difficulties with the techniques using hydride generation, whereas better agreement was obtained for other derivatization techniques with GC/FPD and GC/MS. This paper presents the results of the interlaboratory study. The reference value for TBT in this material is 20±5 ng g−1 (as TBT cation) and the indicative values for dibutyltin (DBT) and monobutyltin (MBT) are 53±19 ng g−1 (as DBT cation) and 257±54 ng g−1 (as MBT cation), respectively. Owing to the difficulties encountered, the reference material was not certified and is considered as a research material to be used for the evaluation of the performance of analytical techniques for the determination of low TBT levels in a difficult matrix.
Quality control in the routine analysis of methylmercury in biological and environmental materials using gas chromatography with electron capture detection
Authors: Rubi E. , Lorenzo R. A. , Casais M. C. , Cela R. 
Published: January 2005

AbstractIn the application of GC ECD procedures for methylmercury analysis and organomercury speciation, frequent column‐treatments must be carried out to maintain the analytical system under statistical control. Often the decision to carry out a new treatment is taken without any statistical assistance. Several quality control techniques have been applied to decide the best time to make these treatments. A Trigg tracking signal chart in combination with a moving estimate of standard deviation charts gives the best indication about the timing of each new treatment.
Methylmercury determination by Purge and Trap–GC–FTIR–AAS after NaBH4 derivatization of an environmental thiosulfate extract
Authors: Filippelli Marco 
Published: January 2005

AbstractA method of detecting methylmercury species (MeHg) and dimethylmercury (DMM) has been studied. MeHg was transformed prior to its determination as methylmercury hydride (MMH) by use of NaBH4. The two volatile forms of organic mercury were detected by a purge and trap (PT) unit in‐line with a gas chromatograph (GC) connected with a Fourier transform infrared spectrometer (FTIR) which was also in‐line with an atomic absorption spectrometer (AAS). Environmental samples were analyzed by this technique. MeHg was detected in thiosulfate extracts of fish and sediment, and MeHg and DMM directly in water samples. Picogram levels of sensitivity were obtained, the limit of detection being 100 pg for MeHg and 50 pg for DMM. The calibration graph was linear for both compounds up to 10 ng as Hg.