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81.
Farré M Asperger D Kantiani L González S Petrovic M Barceló D 《Analytical and bioanalytical chemistry》2008,390(8):1999-2007
In this work, the contributions of triclosan and its metabolite methyl triclosan to the overall acute toxicity of wastewater
were studied using Vibrio fischeri. The protocol used in this paper involved various steps. First, the aquatic toxicities of triclosan and methyl triclosan
were determined for standard substances, and the 50% effective concentrations (EC50) were determined for these compounds. Second, the toxic responses to different mixtures of triclosan, methyl triclosan, and
surfactants were studied in different water matrices, i.e., Milli-Q water, groundwater and wastewater, in order to evaluate
(i) the antagonistic or synergistic effects, and (ii) the influence of the water matrices. Finally, chemical analysis was
used in conjunction with the toxicity results in order to assess the aquatic toxicities of triclosan and its derivative in
wastewaters. In this study, the toxicities of 45 real samples corresponding to the influents and effluents from eight wastewater
treatment works (WWTW) were analyzed. Thirty-one samples were from a wastewater treatment plant (WWTP) equipped with two pilot-scale
membrane bioreactors (MBR), and the influent and the effluent samples after various treatments were characterized via different
chromatographic approaches, including solid-phase extraction (SPE), liquid chromatography coupled to tandem mass spectrometry
(LC–MS/MS), and SPE coupled to gas chromatography–mass spectrometry (GC–MS). The toxicity was determined by measuring the
bioluminescence inhibition of Vibrio fischeri. In order to complete the study and to extrapolate the results to different WWTPs, the toxicity to V. fischeri of samples from seven more plants was analyzed, as were their triclosan and methyl triclosan concentrations. Good agreement
was established between the overall toxicity values and concentrations of the biocides, indicating that triclosan is one of
the major toxic organic pollutants currently found in domestic wastewaters. 相似文献
82.
R. A. Keerthi Shivaraam Dr. Megan Keener Dieuwertje K. Modder Thayalan Rajeshkumar Dr. Ivica Živković Rosario Scopelliti Prof. Laurent Maron Prof. Marinella Mazzanti 《Angewandte Chemie (International ed. in English)》2023,62(23):e202304051
Herein, we report the redox reactivity of a multimetallic uranium complex supported by triphenylsiloxide (−OSiPh3) ligands, where we show that low valent synthons can be stabilized via an unprecedented mechanism involving intramolecular ligand migration. The two- and three-electron reduction of the oxo-bridged diuranium(IV) complex [{(Ph3SiO)3(DME)U}2(μ-O)], 4 , yields the formal “UII/UIV”, 5 , and “UI/UIV”, 6 , complexes via ligand migration and formation of uranium-arene δ-bond interactions. Remarkably, complex 5 effects the two-electron reductive coupling of pyridine affording complex 7 , which demonstrates that the electron-transfer is accompanied by ligand migration, restoring the original ligand arrangement found in 4 . This work provides a new method for controlling the redox reactivity in molecular complexes of unstable, low-valent metal centers, and can lead to the further development of f-elements redox reactivity. 相似文献
83.
84.
Lanthanide(II) Complexes Supported by N,O‐Donor Tripodal Ligands: Synthesis,Structure, and Ligand‐Dependent Redox Behavior
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Julie Andrez Dr. Gülay Bozoklu Dr. Grégory Nocton Dr. Jacques Pécaut Dr. Rosario Scopelliti Dr. Lionel Dubois Dr. Marinella Mazzanti 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(43):15188-15200
The preparation and characterization of a series of complexes of the Yb and Eu cations in the oxidation state II and III with the tetradentate N,O‐donor tripodal ligands (tris(2‐pyridylmethyl)amine (TPA), BPA? (HBPA=bis(2‐pyridylmethyl)(2‐hydroxybenzyl)amine), BPPA? (HBPPA=bis(2‐pyridylmethyl)(3.5‐di‐tert‐butyl‐2‐hydroxybenzyl)amine), and MPA2? (H2MPA=(2‐pyridylmethyl)bis(3.5‐di‐tert‐butyl‐2‐hydroxybenzyl)amine) is reported. The X‐ray crystal structures of the heteroleptic Ln2+ complexes [Ln(TPA)I2] (Ln=Eu, Yb) and [Yb(BPA)I(CH3CN)]2, of the Ln2+ homoleptic [Ln(TPA)2]I2 (Ln=Sm, Eu, Yb) and [Eu(BPA)2] complexes, and of the Ln3+ [Eu(BPPA)2]OTf and [Yb(MPA)2K(dme)2] (dme=dimethoxyethane) complexes have been determined. Cyclic voltammetry studies carried out on the bis‐ligand complexes of Eu3+ and Yb3+ show that the metal center reduction occurs at significantly lower potentials for the BPA? ligand as compared with the TPA ligand. This suggests that the more electron‐rich character of the BPA? ligand results in a higher reducing character of the lanthanide complexes of BPA? compared with those of TPA. The important differences in the stability and reactivity of the investigated complexes are probably due to the observed difference in redox potential. Preliminary reactivity studies show that whereas the bis‐TPA complexes of Eu2+ and Yb2+ do not show any reactivity with heteroallenes, the [Eu(BPA)2] complex reduces CS2 to afford the first example of a lanthanide trithiocarbonate complex. 相似文献
85.
Inside Cover: Lanthanide(II) Complexes Supported by N,O‐Donor Tripodal Ligands: Synthesis,Structure, and Ligand‐Dependent Redox Behavior (Chem. Eur. J. 43/2015)
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86.
Antunes MA Pereira LC Santos IC Mazzanti M Marçalo J Almeida M 《Inorganic chemistry》2011,50(20):9915-9917
The addition of 2,2'-bipyridine to [U(Tp(Me2))(2)I] (1) results in the displacement of the iodide and the formation of the cationic uranium(III) complex [U(Tp(Me2))(2)(bipy)]I (2). This compound was isolated as a dark-green solid in good yield and characterized by IR and NMR spectroscopies, and its molecular structure was determined by single-crystal X-ray diffraction. Studies of its magnetic properties revealed a frequency dependence of magnetization with a blocking temperature of 4.5 K and, at lower temperatures, a slow relaxation of magnetization with an energy barrier of 18.2 cm(-1), characteristic of single-molecule-magnet behavior. 相似文献
87.
Analysis and assessment of the occurrence, the fate and the behavior of nanomaterials in the environment 总被引:1,自引:0,他引:1
Marinella Farré Josep SanchísDamià Barceló 《Trends in analytical chemistry : TRAC》2011,30(3):517-527
Nanomaterials have one dimension <100 nm and possess physico-chemical properties dictated by their unusually small size, large surface area, shape and chemical composition. New properties of nanomaterials have boosted their production and industrial applications in many fields (e.g., microelectronics, catalysis, fuel cells, materials science, textiles, biotechnology and medicine). In biomedical fields, nanomaterials are of the appropriate dimensions to interact with biological matter. However, they may also have negative effects on biological systems. Nanotechnology is a major, innovative, scientific and economic growth area, but the increasing production and use of nanomaterials have led to calls for more information regarding the potential impacts that their release may have on human health and the environment.This review addresses analytical approaches for characterization and quantification of nanomaterials in the environment and recent studies on their occurrence, fate and behavior. 相似文献
88.
High-fidelity solvent-resistant replica molding of hydrophobic polymer surfaces produced by femtosecond laser nanofabrication 总被引:1,自引:0,他引:1
De Marco C Eaton SM Levi M Cerullo G Turri S Osellame R 《Langmuir : the ACS journal of surfaces and colloids》2011,27(13):8391-8395
We demonstrate that hydrophobic areas formed by femtosecond laser irradiation on poly(methyl methacrylate) (PMMA) and polystyrene (PS) polymer substrates can be faithfully replicated on samples of the same material via a solvent-resistant perfluoropolyether (PFPE) elastomer mold. The replicated PMMA and PS samples show nearly identical micro-nanoscale topography and hydrophobic wetting characteristics as the laser-patterned master substrates. This work combines the femtosecond laser capability of spatially tailoring the wettability with a high-resolution parallel replication method, offering the potential for the efficient production of microfluidic devices with selectively tailored flow behavior. 相似文献
89.
Depalo N Carrieri P Comparelli R Striccoli M Agostiano A Bertinetti L Innocenti C Sangregorio C Curri ML 《Langmuir : the ACS journal of surfaces and colloids》2011,27(11):6962-6970
Asymmetric binary nanocrystals (BNCs) formed by a spherical γ-Fe(2)O(3) magnetic domain epitaxially grown onto a lateral facet of a rodlike anatase TiO(2) nanorod have been functionalized with PEG-terminated phospholipids, resulting in a micellar system that enables the BNC dispersion in aqueous solution. The further processability of the obtained water-soluble BNC including PEG lipid micelles and their use in bioconjugation experiments has been successfully demonstrated by covalently binding to bovine serum albumin (BSA). The whole process has also been preliminarily performed on spherical iron oxide nanocrystals (NCs) and TiO(2) nanorods (NRs), which form single structural units in the heterostructures. Each step has been thoroughly monitored by using optical, structural, and electrophoretic techniques. In addition, an investigation of the magnetic behavior of the iron oxide NCs and BNCs, before and after incorporation into PEG lipid micelles and subsequently bioconjugation, has been carried out, revealing that the magnetic characteristics are mostly retained. The proposed approach to achieving water-soluble anisotropic BNCs and their bioconjugates has a large potential in catalysis and biomedicine and offers key functional building blocks for biosensor applications. 相似文献
90.
Fanizza E Altomare M Di Mauro AE Del Sole T Corricelli M Depalo N Comparelli R Agostiano A Striccoli M Curri ML 《Langmuir : the ACS journal of surfaces and colloids》2012,28(14):5964-5974
The fabrication of uniform and patterned nanocrystal (NC) assemblies has been investigated by exploiting the possibility of carefully tailoring colloidal NC surface chemistry and the ability of polyelectrolyte (PE) to functionalize substrates through an electrostatic layer-by-layer (LbL) strategy. Appropriate deposition conditions, substrate functionalization, and post-preparative treatments were selected to tailor the substrate surface chemistry to effectively direct the homogeneous electrostatic-induced assembly of NCs. Water-dispersible luminescent NCs, namely, (CdSe)ZnS and CdS, were differently functionalized by (1) ligand-exchange reaction, (2) growth of a hydrophilic silica shell, and (3) formation of a hydrophilic inclusion complex, thus providing functional NCs stable in a defined pH range. The electrostatically charged functional NCs represent a comprehensive selection of examples of surface-functionalized NCs, which enables the systematic investigation of experimental parameters in NC assembly processes carried out by combining LbL procedures with microcontact printing and also exploiting NC emission, relevant for potential applications, as a prompt and effective probe for evaluating assembly quality. Thus, an ample showcase of combinations has been investigated, and the spectroscopic and morphological features of the resulting NC-based structures have been discussed. 相似文献