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1.
Chem Biodivers ; 21(5): e202301667, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38502834

RESUMEN

In this paper, a new tridentate Schiff base ligand (L) with nitrogen donor atoms and its cadmium(II) complexes with the general formula of CdLX2 (X=Cl-, Br-, I-, SCN-, N3 -, NO3 -) have been synthesized and characterized by physical and spectral (FT/IR, UV-Vis, Mass, and 1H, 13C NMR spectroscopies) methods. Also nano-structured cadmium chloride and bromide complexes were synthesized by sonochemical method and then used to prepare nanostructured cadmium oxide confirmed by XRD and SEM techniques. Thermal behavior of the compounds was studied in the temperature range of 25 to 900 °C under N2 atmosphere at a heating rate of 20 °C/ min. Moreover, thermo-kinetic activation parameters of thermal decomposition steps were calculated according to the Coats-Redfern relationship. Antimicrobial activities of the synthesized compounds against two gram-positive and two gram-negative bacteria such as Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and two fungi of Candida albicans and Aspergillus niger were investigated by well diffusion method. SEM technique was used to monitor the morphological changes of the bacteria treated with the compounds. The 2,2-Diphenyl-1-picrylhydrazyl(DPPH) and the ferric reducing antioxidant power (FRAP) methods were used to evaluate the antioxidant ability of the ligand and its cadmium(II) complexes. In final, the cytotoxicity properties of the ligand and some cadmium(II) complexes against PC3 cancer cells were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) bioassay and nitric oxide (NO) level measurement. The morphological changes of prostate cancer (PC3) cells due to treatment with the ligand and its complexes confirmed their anticancer effectiveness.


Asunto(s)
Antineoplásicos , Antioxidantes , Cadmio , Complejos de Coordinación , Pruebas de Sensibilidad Microbiana , Antioxidantes/farmacología , Antioxidantes/síntesis química , Antioxidantes/química , Humanos , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Cadmio/química , Cadmio/farmacología , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Antibacterianos/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Antifúngicos/farmacología , Antifúngicos/síntesis química , Antifúngicos/química , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Bacterias Grampositivas/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Estructura Molecular , Bases de Schiff/química , Bases de Schiff/farmacología , Bases de Schiff/síntesis química , Compuestos de Bifenilo/antagonistas & inhibidores , Compuestos de Bifenilo/química , Compuestos de Bifenilo/farmacología , Candida albicans/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Hongos/efectos de los fármacos , Relación Estructura-Actividad , Picratos/antagonistas & inhibidores , Antiinfecciosos/farmacología , Antiinfecciosos/síntesis química , Antiinfecciosos/química , Temperatura
2.
Ultrason Sonochem ; 52: 244-256, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30563797

RESUMEN

A new nanostructured cadmium complex containing a tridentate Schiff base ligand was sonochemically synthesized and characterized by XRPD, FT/IR, NMR, and single crystal X-ray crystallography. Structural data showed that cadmium(II) ion is surrounded by three nitrogen atoms of Schiff base ligand and two iodide anions. The crystal packing was contained the intermolecular interactions such as CH⋯O, CH⋯I and π⋯π interactions organizing the self-assembly process. Hirshfeld surfaces and corresponding fingerprint plots have been used for investigation of the nature and proportion of interactions in the crystal packing. FT/IR, NMR and XRD data were in agreement with the X-ray structure and confirm the phase purity of the prepared sample. The molecular structure of the complex was optimized by density functional theory (DFT) calculation at the B3LYP/LANL2DZ level of theory and the results were compared with experimental ones. For more concise study of structure and spectral aspects of the complex, natural bond orbital (NBO) analysis and time-dependent density functional theory (TD-DFT) have been also performed. Thermal stability of the cadmium iodide complex was investigated by thermogravimetric analysis (TGA). Finally, cadmium oxide nanoparticles was prepared by direct calcination of CdLI2 complex as a new precursor.

3.
Ultrason Sonochem ; 46: 26-35, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29739510

RESUMEN

A nanostructured cationic zinc nitrate complex with a formula of [ZnLNO3]NO3 (where L = (N2E,N2'E)-N1,N1'-(ethane-1,2-diyl)bis(N2-((E)-3-phenylallylidene)ethane-1,2-diamine)) was prepared by sonochemical process and characterized by single crystal X-ray crystallography, scanning electron microscopy (SEM), FT-IR and NMR spectroscopy and X-ray powder diffraction (XRPD). The X-ray analysis demonstrates the formation of a cationic complex that metal center is five-coordinated by four nitrogen atom from Schiff base ligand and one oxygen atom from nitrate group. The crystal packing analysis demonstrates the essential role of the nitrate groups in the organization of supramolecular structure. The morphology and size of ultrasound-assisted synthesized zinc nitrate complex have been investigated using scanning electron microscopy (SEM) by changing parameters such as the concentration of initial reactants, the sonication power and reaction temperature. In addition the calcination of zinc nitrate complex in air atmosphere led to production of zinc oxide nanoparticles.

4.
Photochem Photobiol Sci ; 17(2): 245-255, 2018 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-29327003

RESUMEN

In this work, the use of carbon dots (CDs) as a complexing agent and sensitizer in a polymeric matrix for determination of copper(ii) by UV-vis spectroscopy is reported for the first time. A new and highly selective Schiff base, namely, (N',N'''E,N',N'''E)-N',N'''-((((2-hydroxypropane-1,3-diyl)bis(oxy))bis(2,1-phenylene))bis(methan-ylylidene))di(isonicotinohydrazide) (NHBMDI), was also incorporated in the polymeric matrix. For the first time, the membrane composition of the proposed optical sensor including NHBMDI as the ionophore, tetraphenylborate (NaTPB) as the anionic additive, dibutyl phthalate (DBP) as the plasticizer and polyvinyl chloride (PVC) as the immobilizer was optimized through central composite design combined with the desirability function approach (DFA) because this method saves material and time consumption and is therefore cost effective. The synthesized CDs were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The fluorescence quantum yield of the synthesized CDs was found to be 6.4% by using quinine sulfate as the reference. The characterization of the prepared membrane sensor was investigated by field emission scanning electron microscope (FE-SEM) and atomic force microscopy (AFM).The response of the optode was based on the strong absorbance of NHBMDI and CDs upon exposure to Cu(ii) ions with the maximum wavelength at 371 nm. The proposed sensor exhibited a linear response in the concentration range of 1.2 × 10-6-4.56 × 10-5 mol L-1 with a detection limit of 7.1 × 10-7 mol L-1, which is lower than U.S. Environmental Protection Agency's defined limit (20 µM). Furthermore, the proposed optode displayed good selectivity toward Cu(ii) ions in comparison with common coexisting cations with satisfactory repeatability and reproducibility. The sensor was applied successfully for determination of copper(ii) ions in water samples.

5.
Ultrason Sonochem ; 41: 590-599, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29137791

RESUMEN

The nitrate complexes of group 12 elements with a tridentate Schiff base ligand (L = (E)-N1-((E)-3- phenylallylidene)-N2-(2-((E)-((E)-3-phenylallylidene) amino)ethyl) ethane-1,2-diamine) were synthesized via sonochemical process and characterized by various physical and chemical methods. The structural analysis of the zinc nitrate complex by single crystal X-ray diffraction analysis shows that the central atom is seven-coordinated by three nitrogen atoms from the Schiff base ligand as well as four oxygen atoms from two different nitrate anions. The geometry around the metal center can be described as a distorted pentagonal bipyramid. The crystal packing analysis of zinc nitrate complex indicates that the intermolecular interactions related to nitrate groups plays the essential role in the orientation of supramolecular structure. Hirshfeld surfaces (HS) and their corresponding fingerprint plots (FP) have been also used for further investigation of crystal structure of zinc nitrate complex. Furthermore thermal analyses (TG/DTG) of three nanostructure complexes were carried out and discussed. Finally, direct thermolysis of zinc and cadmium nitrate complexes in air atmosphere led to the production of zinc and cadmium oxide nanoparticles.

6.
Mater Sci Eng C Mater Biol Appl ; 77: 229-244, 2017 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-28532025

RESUMEN

A new bidentate Schiff base ligand named as N,N'-bis((E)-3-phenylallylidene)butane-1,4-diamine (L) and three its zinc halide complexes were synthesized and characterized by FT-IR, 1H NMR, 13C NMR and UV-Vis spectroscopy. The crystal structure of zinc bromide and iodide complexes were characterized using single crystal X-ray diffraction. The two structures are isomorphous, crystallizing in the monoclinic crystal system with space group C2/c with closely similar unit cell dimensions. In these complexes, the Zn(II) ion is in the center of a distorted tetrahedral environment completed by two iminic nitrogen atoms of Schiff base ligand and two halide anions. The analysis of crystal structures shows that intermolecular interactions such as CH⋯halogen, π⋯π and CH⋯π interactions have effective role in stabilization of complexes structure. Intermolecular interactions were more analyzed using 3D Hirshfeld surface analysis and corresponding 2D fingerprint plots. Furthermore, structural optimization by DFT calculations at the B3LYP/LANL2DZ level have been performed and then compared with the experimental data. Time-dependent density functional theory (TDDFT) has been also used to calculate the electronic transitions of molecules at B3LYP/LANL2DZ level using the optimized ground-state geometries. NBO analysis was applied for investigation of intra and inter-molecular bonding and conjugative interaction in molecular systems. Schiff base ligand and their zinc complexes have been screened for their antibacterial and antifungal activities by disc diffusion method. Thermal behaviors of all compounds were studied by TG/DTG analysis data. Also, nanostructures of zinc complexes were synthesized by sonochemical method and characterized by FT-IR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). ZnO nanoparticles were simply prepared by calcination of zinc iodide complex as new precursor at 600°C.


Asunto(s)
Cristalografía por Rayos X , Antiinfecciosos , Complejos de Coordinación , Bases de Schiff , Espectroscopía Infrarroja por Transformada de Fourier , Zinc
7.
Mater Sci Eng C Mater Biol Appl ; 61: 809-23, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26838912

RESUMEN

Some new five coordinated ZnLX2 complexes, where L is N3-Schiff base ligand obtained by condensation reaction between diethylenetriamine and (E)-3-(2-nitrophenyl)acrylaldehyde and X (Cl(-), Br(-), I(-), N3(-) and NCS(-)), were synthesized and characterized by FT-IR, (1)H and (13)CNMR, UV-visible, ESI-mass spectra and molar conductivity measurements. The structures of zinc iodide and thiocyanate complexes were determined by X-ray crystallographic analysis. The X-ray results showed that the Zn (II) center in these complexes is five-coordinated in a distorted trigonal-bipyramidal configuration. Zinc iodide and thiocyanate complexes crystallize in the monoclinic and triclinic systems with space groups of C2/c and P1- with eight and two molecules per unit cell respectively. The crystal packing of the complexes consists of intermolecular interactions such as C-H(…)O and C-H(…)I, C-H(···)S, N(…)O, together with π-π stacking and some other unexpected interactions. The mentioned interactions cause three-dimensional supramolecular structure in the solid state. Zinc complexes were also prepared in nano-structure by sonochemical method confirmed by XRD, SEM and TEM analyses. Moreover, ZnO nanoparticles were synthesized by direct thermolysis of zinc iodide complex. Furthermore, antimicrobial and thermal properties of the compounds were completely investigated.


Asunto(s)
Antiinfecciosos/síntesis química , Complejos de Coordinación/síntesis química , Zinc/química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Aspergillus oryzae/efectos de los fármacos , Candida albicans/efectos de los fármacos , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Cristalografía por Rayos X , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Enlace de Hidrógeno , Ligandos , Espectroscopía de Resonancia Magnética , Nanopartículas del Metal/química , Conformación Molecular , Bases de Schiff/química , Espectroscopía Infrarroja por Transformada de Fourier
8.
Mater Sci Eng C Mater Biol Appl ; 55: 462-70, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26117778

RESUMEN

Some new cadmium(II) Schiff base complexes CdLX2 (where X=Cl(-), Br(-), I(-), SCN(-) and N3(-) and L=N,N-bis((E)-3-(4-(dimethylamino)phenyl)allylidene)benzene-1,2-diamine) were synthesized and characterized by elemental analysis, FT-IR, UV-visible, (1)HNMR spectra, and conductivity measurements. Moreover, the structure of the CdLI2 was determined by single crystal X-ray crystallography. CdLI2 crystallizes in a triclinic system with space group P 1̅. The molecular structure shows distorted tetrahedral coordination geometry. The CH....π and π-π stacking interactions connect the molecules to a supramolecular network. The thermal properties of the compounds were investigated from the room temperature to 800 °C with a heating rate of 10 °C/min and decomposition activation parameters were evaluated from the TG/DTG plots. Antibacterial/antifungal activities of the compounds were screened by the disk diffusion method against the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, the Gram-positive bacteria Staphylococcus aureus and Bacillus subtilis and the fungi strain Aspergillus niger and Candida albicans. The antimicrobial activities were determined for all compounds and the complexation was found to enhance the inhibitory activity. Finally, the DNA cleavage potential of the compounds was investigated by agarose gel electrophoresis method.


Asunto(s)
Antiinfecciosos/farmacología , ADN/efectos de los fármacos , Bases de Schiff/química , Cristalografía por Rayos X , Hidrólisis , Pruebas de Sensibilidad Microbiana , Espectroscopía de Protones por Resonancia Magnética
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 147: 139-50, 2015 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-25835377

RESUMEN

In this research, template synthesis and crystal structure of a new HgLI2 complex are presented (L=N(1)-(4-nitrobenzylidene)-N(2)-(2-((E)-(4-nitrobenzylidene)amino)ethyl)ethane-1,2-diamine). The mercury complex crystallizes in the triclinic system with space group of P1¯. The crystal structure of the complex shows a distorted trigonal bipyramidal geometry around the mercury(II) center; including two I and an N atoms of Schiff base ligand in equatorial plane and two iminic N atoms in axial positions. Two five membered mercury containing rings [Hg(-N-C-C-N-)] are found in the structure. Some C-H⋯O, N⋯O and π⋯π intermolecular interactions causes a supra-molecular network in the solid-state. In addition to crystal structure analysis, density functional theory (DFT) study at the B3LYP/LanL2DZ level of theory has been also performed on the structure. Thereafter some theoretical structural and spectral data were compared with experimental results. Furthermore, total energy levels of HOMO and LUMO orbitals, molecular electrostatic potential, Mullikan atomic charges, thermodynamic and polarizability properties of the complex were calculated. Finally the mercury complex was prepared in nano-structure size confirmed by SEM and XRD analyses. The particles size of the titled complex was evaluated under 40 nm based on Sherrer's formula.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 138: 517-28, 2015 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-25528511

RESUMEN

In this work, synthesis of some new five coordinated zinc halide/pseudo-halide complexes of a N3-tridentate ligand is presented. All complexes were subjected to spectroscopic and physical methods such as FT-IR, UV-visible, (1)H and (13)C NMR spectra, thermal analyses and conductivity measurements for identification. Based on spectral data, the general formula of ZnLX2 (X=Cl(-), Br(-), I(-), SCN(-) and N3(-)) was proposed for the zinc complexes. Zinc complexes have been also prepared in nano-structure sizes under ultrasonic irradiation. X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were applied for confirmation of nano-structure character for the complexes. Among the complexes, zinc azide complex structure was analyzed by X-ray crystallography. This complex crystallizes as a triplet in trigonal system with space group of P31. The coordination sphere around the zinc center is well shown as a distorted trigonal bipyramidal with three nitrogen atoms from Schiff base ligand and two terminal azide nitrogen atoms attached to zinc ion. Various intermolecular interactions such as NH⋯N, CH⋯N and CH⋯π hydrogen bonding interactions stabilize crystalline lattice so that they causes a three dimensional supramolecular structure for the complex. In vitro screening of the compounds for their antimicrobial activities showed that ZnLI2, ZnL(N3)2, ZnLCl2 and ZnL(NCS)2 were found as the most effective compound against bacteria of Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli respectively. Also ZnLI2 and ZnLCl2 complexes were found more effective against two selected fungi than others. Finally, thermal behaviors of the zinc complexes showed that they are decomposed via 2-4 thermal steps from room temperature up to 1000°C.


Asunto(s)
Nanopartículas del Metal/química , Bases de Schiff/química , Antibacterianos/química , Azidas/química , Bacillus subtilis/efectos de los fármacos , Cristalografía por Rayos X , Escherichia coli/efectos de los fármacos , Halógenos/química , Calor , Enlace de Hidrógeno , Ligandos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Conformación Molecular , Pseudomonas aeruginosa/efectos de los fármacos , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , Vibración , Difracción de Rayos X , Zinc/química
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 137: 389-96, 2015 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-25233031

RESUMEN

Two new cadmium(II) complexes with the formula of CdL2(NCS)2 and CdL2(N3)2 (in which L is 2,2-dimethyl-N,N'-bis-(3-phenyl-allylidene)-propane-1,3-diamine) have been synthesized and characterized by elemental analysis, molar conductivity measurements, FT/IR, UV-Visible, (1)H and (13)C NMR spectra and X-ray studies. The crystal structure analysis of CdL2(NCS)2 indicated that it crystallizes in orthorhombic system with space group of Pbca. Two Schiff base ligands are bonded to cadmium(II) ion as N2-donor chelate. Coordination geometry around the cadmium ion was found to be partially distorted octahedron. The Cd-Nimine bond distances are found in the range of 2.363(2)-2.427(2)Å while the Cd-Nisothiocyanate bond distances are 2.287(2)Å and 2.310(2)Å. The existence of C-H⋯π and C-H⋯S interactions in the CdL2(NCS)2 crystal leads to a supramolecular structure in its network. Then cadmium complexes were screened in vitro for their antibacterial and antifungal activities against two Gram-negative and two Gram-positive bacteria and also against Candida albicans as a fungus. Moreover, the compounds were subjected for DNA-cleavage potential by gel electrophoresis method. Finally thermo-gravimetric analysis of the complexes was applied for thermal behavior studies and then some thermo-kinetics activation parameters were evaluated.


Asunto(s)
Antiinfecciosos/farmacología , Cadmio/química , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Antiinfecciosos/síntesis química , Antiinfecciosos/química , Candida albicans/efectos de los fármacos , Técnicas de Química Sintética , Cristalografía por Rayos X , ADN/química , ADN/metabolismo , Análisis Diferencial Térmico , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Bases de Schiff , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier
12.
Hum Exp Toxicol ; 32(7): 687-97, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23821588

RESUMEN

In the present work, multiwalled carbon nanotube (MWCNT) chemically modified with (3-mercaptopropyl) silanetriolate is efficiently used for the solid-phase extraction of Cu(2+), Ag(+), Cd(2+), Pb(2+), Zn(2+) and Mn(2+) ions prior to their flame atomic absorption spectrometric determination. The influences of the various analytical parameters, including pH, amounts of solid phase, sample volume and eluent conditions and so on, on the recoveries of target analytes were investigated and optimized by one at a time optimization method. The influences of alkaline, alkaline earth and some transition metals on the adsorption and elution of the analytes were also examined. The detection limits for all understudied metal ions were between 1.4 and 2.8 ng mL(-1) (3Sb, n = 10). The evaluation of the thermodynamic parameters such as enthalpy (positive value), Gibbs free energy (negative value) in addition to high value of entropy shows the endothermic and spontaneous nature of sorption process. Following the optimization of variables, the adsorption process follows the intraparticle kinetic model with R (2) of 0.98 and the Langmuir isotherm with high correlation coefficient (R (2) > 0.95). The procedure was applied for the analytes determination in the food samples with satisfactory results (recoveries >95% and relative standard deviation's (RSD) lower than 4%).


Asunto(s)
Metales Pesados/análisis , Nanotubos de Carbono/química , Silanos/química , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , Nanotubos de Carbono/ultraestructura , Rosmarinus/química , Extracción en Fase Sólida , Espectrofotometría Atómica , Espectroscopía Infrarroja por Transformada de Fourier , Spinacia oleracea/química , Thymus (Planta)/química
13.
Hum Exp Toxicol ; 32(4): 371-8, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23613484

RESUMEN

A solid phase extraction method for enrichment-separation and the determination of cobalt (Co(2+)), copper (Cu(2+)), nickel (Ni(2+)), zinc (Zn(2+)) and lead (Pb(2+)) ions in real samples has been proposed. The influences of some analytical parameters like pH, flow rate, eluent type and interference of matrix ions on recoveries of analytes were optimized. The limits of detection were found in the range of 1.6-3.9 µg L(-1), while preconcentration factor for all understudy metal ions were found to be 166 with loading half time (t 1/2) less than 10 min. The procedure was applied for the enrichment-separation of analyte ions in environmental samples with recoveries higher than 94.8% and relative SD <4.9% (N = 5).


Asunto(s)
Contaminantes Ambientales/análisis , Metales Pesados/análisis , Ácidos Polimetacrílicos/química , Bases de Schiff/química , Compuestos de Sulfhidrilo/química , Absorción , Contaminantes Ambientales/química , Concentración de Iones de Hidrógeno , Metales Pesados/química , Extracción en Fase Sólida/métodos , Espectrofotometría Atómica/métodos
14.
Mater Sci Eng C Mater Biol Appl ; 33(4): 2338-44, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23498267

RESUMEN

The present study involves the development of solid-phase extraction (SPE) procedure for the preconcentration of trace amounts of copper (Cu(2+)), iron (Fe(3+)) and zinc (Zn(2+)) ions on duolite XAD 761 modified by bis(2-hydroxyacetophenone)-2,2-dimethyl-1,3-propanediimine(BHAPDMPDI). The complexation between the metal ions and the proposed ligand was investigated potentiometrically. The metal ions retained on the sorbent were quantitatively determined via complexation with BHAPDMPDI. The complexed metal ions were efficiently eluted using 6 mL of 4 mol L(-1) nitric acid in acetone. The influences of the analytical parameters, including pH, amounts of the ligand and the solid phase, eluent conditions and sample volume, on the recoveries of the metal ions were optimized. Using the optimized parameters, the linear response of the SPE method for Cu(2+), Zn(2+) and Fe(3+) ions were in the ranges of 0.01-0.34, 0.01-0.28 and 0.02-0.31 µg mL(-1), respectively, and the detection limits for Cu(2+), Zn(2+) and Fe(3+) ions were 1.8, 1.6 and 2.4 µg mL(-1), respectively. The proposed method exhibits a preconcentration factor of 208 for all of the ions studied and an enhancement factor for Cu(2+), Fe(3+) and Zn(2+) ions of 34, 28 and 38, respectively. The presented results demonstrate the successful application of the proposed method for the determination of these metal ions in some real samples with high recoveries (> 95%) and reasonable relative standard deviation (RDS <5%).


Asunto(s)
Análisis de los Alimentos/métodos , Metales Pesados/análisis , Resinas Sintéticas/química , Bases de Schiff/química , Extracción en Fase Sólida/métodos , Espectrofotometría Atómica/métodos , Cobre/análisis , Concentración de Iones de Hidrógeno , Iones , Hierro/análisis , Ligandos , Octoxinol/química , Potenciometría , Protones , Reproducibilidad de los Resultados , Soluciones , Solventes/química , Zinc/análisis
15.
Environ Monit Assess ; 184(11): 6583-91, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22105849

RESUMEN

In this work, two N/S-containing chelating agents 2-(4-methoxybenzylideneamino)thiophenol (2-4-MBAT) and 2-(4-chlorobenzylideneamino) benzenethiol (2-4-CBABT) were synthesized as new sorbents and were used for preconcentration of Zn(2+) and Cu(2+) ions in food and vegetable samples. In the proposed procedure, the trace amount of Zn(2+) and Cu(2+) ions from 250 mL of sample solution at pH = 5.0 was preconcentrated by 1 g of activated carbon (AC) loaded with 15 mg of 2-4-MBAT and 2-4-CBABT separately. The breakthrough volumes (maximum sample volume that their metal ions quantitatively can be enriched) for solid-phase extraction (SPE) procedure based on the AC modified with 2-4-MBAT and 2-4-CBABT were 800 and 750 mL, respectively. The sorbed Zn(2+) and Cu(2+) ions were efficiently eluted by 8 mL of 4 mol L(-1) HNO(3) and preconcentration factor of 112.5 and 93.7 and experimental enhancement factor of 30 and 35 ions were obtained for Zn(2+) and Cu(2+), respectively. The application of this enrichment procedure allowed the extraction of trace metal ions with recoveries exceeding of 90%.


Asunto(s)
Carbón Orgánico/química , Cobre/análisis , Análisis de los Alimentos/métodos , Contaminantes del Suelo/análisis , Verduras/química , Zinc/análisis , Quelantes/química , Cobre/química , Contaminación de Alimentos/análisis , Contaminantes del Suelo/química , Extracción en Fase Sólida , Zinc/química
16.
J Hazard Mater ; 187(1-3): 75-81, 2011 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-21282004

RESUMEN

A simple and selective method was used for the preconcentration and determination of uranium(VI) by solid-phase extraction (SPE). In this method, a column of alumina modified with sodium dodecyl sulfate (SDS) and a new Schiff's base ligand was prepared for the preconcentration of trace uranyl(VI) from water samples. The uranium(VI) was completely eluted with HCl 2M and determined by a spectrophotometeric method with Arsenazo(III). The preconcentration steps were studied with regard to experimental parameters such as amount of extractant, type, volume and concentration of eluent, pH, flow rate of sample source and tolerance limit of diverse ions on the recovery of uranyl ion. A preconcentration factor more than 200 was achieved and the average recovery of uranyl(VI) was 99.5%. The relative standard deviation was 1.1% for 10 replicate determinations of uranyl(VI) ion in a solution with a concentration of 5 µg mL(-1). This method was successfully used for the determination of spiked uranium in natural water samples.


Asunto(s)
Óxido de Aluminio/química , Bases de Schiff , Dodecil Sulfato de Sodio/química , Uranio/química , Adsorción , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Estándares de Referencia , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta
17.
Food Chem Toxicol ; 49(1): 208-14, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20969912

RESUMEN

A method for preconcentration of trace heavy metal ions in environmental samples has been reported. The presented method is based on the sorption of Cr(3+), Co(2+), Cu(2+), Fe(3+), Ni(2+), and Zn(2+) ions with 2-(2,4-dichlorobenzylideneamino) benzenethiol as respective chelate on modified Duolite XAD 761. The metals content of the sorbed complexes are eluted using 6 ml of 4M nitric acid. The influences of the analytical parameters including pH, amount of ligand and solid phase and condition of eluting solution, the effects of matrix ions on the retentions of the analytes were examined. The recoveries of analytes are generally higher than 94% and the RSD is between 1.5% and 2.2%. The method has been successfully applied for the evaluation of understudy metals content in some food samples.


Asunto(s)
Quelantes/química , Análisis de los Alimentos , Metales/análisis , Resinas Sintéticas , Bases de Schiff , Reproducibilidad de los Resultados , Extracción en Fase Sólida , Oligoelementos/análisis
18.
Environ Monit Assess ; 174(1-4): 171-86, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20502961

RESUMEN

A sensitive and simple method based on modification of Sepabeads SP70 by 4-((E)-3-phenylallylidene) amino) benzenethiol for the simultaneous preconcentration of trace amounts of copper (Cu), nickel (Ni), chromium (Cr), and zinc (Zn) ions in some real samples has been reported. The metal ions which are retained as respective complexes on solid phase were eluted with 8 ml of 4 M nitric acid. The influences of different analytical parameters including pH, ligand amount and Sepabeads SP70 and SDS amount, eluting solutions, and sample volume on metal ions recoveries were investigated. The effects of matrix ions on the retentions of the analytes were also examined. The recoveries of analytes were generally >95% with RSD between 0.74 and 0.88. The proposed method has been successfully applied for the determination of these metals in some real samples with complex matrices.


Asunto(s)
Metales/química , Plantas/química , Dodecil Sulfato de Sodio/química , Suelo/química , Compuestos de Sulfhidrilo/química , Agua/química , Espectrofotometría Infrarroja
19.
Food Chem Toxicol ; 48(2): 482-9, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19883718

RESUMEN

A sensitive and simple method for the simultaneous preconcentration of trace amount of Cu2+, Ni2+ and Cr3+ ions in some real samples has been reported. In this method these elements are adsorbed as respective complex with Bis(2-hydroxyacetophenone)-1,2-propanediimine (BHAPPDI) on Diaion SP-850 and the retained metal ions are eluted using 8 ml of 4 M nitric acid. The influences of the analytical parameters including pH, solid phase ingredients amount and condition of eluting solution and sample volume were investigated. The effects of matrix ions on retentions of the analytes were also examined. The recoveries of analytes were generally higher than 90% with a relatively low RSD. The method has been successfully applied for these metal ions contents evaluation in some food and environmental samples.


Asunto(s)
Resinas Acrílicas/química , Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Metales Pesados/química , Extracción en Fase Sólida/métodos , Adsorción , Cromo/análisis , Cromo/química , Cobre/análisis , Cobre/química , Monitoreo del Ambiente , Análisis de los Alimentos/instrumentación , Concentración de Iones de Hidrógeno , Ligandos , Metales Pesados/análisis , Níquel/análisis , Níquel/química
20.
J Hazard Mater ; 170(1): 169-74, 2009 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-19481865

RESUMEN

A sensitive and simple method for the preconcentration of copper (II) ions has been reported. The method is based on the adsorption of copper ion N(1), N(2)-bis(4-fluorobenzylidene)ethane-1,2-diamine loaded on Sepabeads. The sorpted copper content was eluted by 8 ml of 4M nitric acid in acetone. The influences of the analytical parameters including pH and sample volume were investigated. The interference effects of matrix ions on the retentions of the copper (II) ions were also examined. The recovery of understudy analyte was generally higher than 95%. The method has been successfully applied to the evaluation of copper contents in some real samples including water samples, vegetable samples and milk samples.


Asunto(s)
Cobre/aislamiento & purificación , Diaminas/química , Adsorción , Animales , Análisis de los Alimentos/métodos , Concentración de Iones de Hidrógeno , Iones , Microesferas , Leche/química , Oligoelementos/aislamiento & purificación , Verduras/química , Agua/química
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