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Afsaneh Safavi - One of the best experts on this subject based on the ideXlab platform.
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flotation separation and icp aes determination of ultra trace amounts of copper cadmium nickel and cobalt using 2 aminocyclopentene 1 Dithiocarboxylic Acid
Analytical Sciences, 2005Co-Authors: Mojtaba Shamsipur, Omid Reza Hashemi, Afsaneh SafaviAbstract:A rapid flotation method for separation and enrichment of ultra trace amounts of copper(II), cadmium(II), nickel(II) and cobalt(II) ions from water samples is established. At pH 6.5 and with sodium dodecylsulfate used as a foaming reagent, Cu2+, Cd2+, Ni2+ and Co2+ were separated simultaneously with 2-aminocyclopentene-1-Dithiocarboxylic Acid (ACDA) added to 1 l of aqueous solution. The proposed procedure of preconcentration is applied prior to the determination of these four analytes using inductivity coupled plasma-atomic emission spectrometry (ICP-AES). The effects of pH, concentration of ACDA, applicability of different surfactants and foreign ions on the separation efficiency were investigated. The preconcentration factor of the method is 1000 and the detection limits of copper(II), cadmium(II), nickel(II) and cobalt(II) ions are 0.078, 0.075, 0.072 and 0.080 ng ml-1, respectively.
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cloud point extraction preconcentration and simultaneous spectrophotometric determination of nickel and cobalt in water samples
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2004Co-Authors: Afsaneh Safavi, Hamid Abdollahi, M Hormozi R Nezhad, Reza KamaliAbstract:Abstract Cloud point extraction has been used for the preconcentration and simultaneous spectrophotometric determination of nickel and cobalt after the formation of a complex with 2-amino-cyclopentene-1-Dithiocarboxylic Acid (ACDA), and latter analysis by spectrophotometer using Triton X-114 as surfactant. The parameters affecting the separation phase and detection process were optimized. Under the optimum experimental conditions (i.e. pH=5, 0.07 mM ACDA, Triton X-114 = 0.25% (w/v)), calibration graphs were linear in the range of 20–500 and 20–200 μg l−1 with detection limits of 10 and 7.5 μg l−1 for Ni and Co, respectively. The method was applied to the determination of Ni and Co in natural and waste water samples with satisfactory results.
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spectrophotometric study on micelle mediated shift in kinetic and equilibrium of complex formation between ni2 and 2 amino cyclopentene 1 Dithiocarboxylic Acid
Microchemical Journal, 2001Co-Authors: Afsaneh Safavi, H AbdollahiAbstract:Abstract The significant shift in kinetic and equilibrium behavior of complex formation between Ni 2+ and 2-amino-cyclopentene-1-Dithiocarboxylic Acid (ACDA) in a solution of ionic surfactant cetyltrimethylammonium bromide (CTAB) was studied spectrophotometrically in 0.1 M NaBr medium at 30°C. A model based on distributions of ligand (ACDA) and complex [Ni(ACDA) 2 ] between aqueous and micellar pseudo-phase was applied to account for the shift in the apparent formation constant and observed pseudo-first order rate constant. Partition constants were evaluated by using a technique based on the principal component analysis method. The proposed model, states that the reaction occurs only in the aqueous phase. Apparent formation constants and the observed rate constants decreased with increasing the micelle concentration. Good agreement between experimental and calculated values indicates that, the applied model provides a good description of the micellar effects on complex formation between Ni 2+ and ACDA.
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electroanalytical behaviour of 2 aminocyclopentene 1 Dithiocarboxylic Acid and its n substituted derivatives at mercury electrodes
Analytical Letters, 1992Co-Authors: Afsaneh Safavi, M B GholivandAbstract:Abstract The electroanalytical behaviour of 2-aminocyclopentene-1-Dithiocarboxylic Acid and some of its derivatives has been investigated in aqueous or aqueous-ethanolic solutions at the mercury electrode. All the compounds studied give only one-electron anodic wave. The various adsorption phenomena are probably caused by varying orientation of the mercury compounds on the electrode surface. Although the overall electrode reaction mechanism is the same for all the derivatives, the current flowing in the main anodic wave is determined by the nature of the film of the particular insoluble mercury(II) products deposited on the electrode and varies with the substituent group on nitrogen.
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analytical data spectrophotometric determination of the Acidity constants of 2 amino cyclopentene 1 Dithiocarboxylic Acid and some of its derivatives
Talanta, 1992Co-Authors: M B Gholivand, Afsaneh SafaviAbstract:Abstract The Acidity constants of 2-amino cyclopentene-1-Dithiocarboxylic Acid (ACDA) and some of its derivatives have been determined spectrophotometrically, at 25° and at different mole fractions of ethanol in water. In all solvent mixtures used, the Acidity constants vary in the order ACDA > N -methyl-ACDA > N -ethyl-ACDA > N -butyl-ACDA.
R Guiraud - One of the best experts on this subject based on the ideXlab platform.
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technetium labeling of bi tri and tetradentate ligands derived from 2 aminocyclopentene 1 Dithiocarboxylic Acid characterization and biodistribution of their oxo and nitrido 99mtechnetium complexes
Nuclear Medicine and Biology, 1996Co-Authors: Hafid Belhadjtahar, Y Coulais, G Cros, M H Darbieu, J A M Tafani, J Fabre, J P Esquerre, R GuiraudAbstract:Abstract We have synthesized and characterized seven ligands derived from 2-aminocyclopentene-1-Dithiocarboxylic Acid with different donor sets (SN 2− , SNO 2− , SNN 2− , SNNO 3− and SNNN 3− ) and different substituents on the sulfur moieties -SR (with R=H, CH 3 or C 2 H 5 O(CH 3 )CH). With five of these ligands technetium nitrido complexes have been obtained with high yields (over 95%) using rather harsh conditions (pH ≈ 1, temperature ≥ 80 °C), whereas for technetium oxo complexes similar high yields were only obtained with two ligands but with mild conditions (pH = 7–8, temperature ≈ 50 °C). Changing an OH group for an NH 2 has a drastic effect upon labeling yields. The possibility of complexing ligands as either oxo (TcO) 3+ or nitrido (TcN) 2+ derivatives increases the number of available labeled agents with different overall change and consequently with different biological behavior.
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synthesis and characterization of neutral oxorhenium v and nitridotechnetium v complexes with a tetradentate n2s2 unsaturated ligand derived from Dithiocarboxylic Acid
Inorganica Chimica Acta, 1994Co-Authors: G Cros, R Guiraud, Belhadj H Tahar, D De Montauzon, A Gleizes, Yvon Coulais, E Bellande, R PasqualiniAbstract:Abstract Neutral complexes of technetium(V) and rhenium(V) of the type TcN(L2) and ReO(L2)CI, where L2 corresponds to the dianionic form of the tetradentate N 2 S 2 ligand N , N ′-ethylene bis(methyl 2-aminocyclopentane-l-dithiocarboxylate), were prepared by substitution reaction on the starting materials 99 TcNCl 2 (PPh 3 ) 2 and ReOCl 3 (PPh 3 ) 2 , respectively. The complexes were characterized by elemental analysis, IR, NMR spectroscopy and conductimetry. The molecular and crystal structure of the nitrido complex TcN(L2) was determined by single-crystal X-ray diffraction technique (monoclinic P 2 1 / c , a = 13.380(6), b = 9.945(2), c = 15.839 A, β = 113.91(3)°). The electrochemical behaviour of the nitrido complex was investigated.
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synthesis characterization and biodistribution of new 99mtc oxo and nitrido complexes with bi and tetradendate unsaturated ns and n2s2 schiff bases derived from 2 aminocyclopentene 1 Dithiocarboxylic Acid as potential heart imaging agents
Nuclear Medicine and Biology, 1994Co-Authors: Y Coulais, Hafid Belhadjtahar, G Cros, M H Darbieu, J A M Tafani, E Bellande, R Pasqualini, R GuiraudAbstract:Abstract The synthesis, characterization and 99m Tc labelling of unsaturated diamino dithiol ligands with methyl dithiocarboxylate functions: 2-aminocyclopentene-1-Dithiocarboxylic methyl ester (H 2 L1), N,N′ -ethylene bis (methyl 2-aminocyclopentene-1-dithiocarboxylate) (H 2 L 2 ) and N,N′ -propylene bis (methyl 2-aminocyclopentene-1-dithiocarboxylate) (H 2 L3) are described. Cationic oxo (TcO) and neutral nitrido (TcN) complexes were obtained. Biodistribution studies in rat showed a good heart uptake of 99m TcN-L2 (2% ID at 5 min) with a high heart-to-blood ratio (5.8 at 5 min), but this complex also exhibited high lung and liver uptake.
Enrique Iniguez - One of the best experts on this subject based on the ideXlab platform.
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synthesis and thermal properties of iib group derived ϵ caprolactam 3 Dithiocarboxylic Acid complexes
Journal of Coordination Chemistry, 2007Co-Authors: Enrique Iniguez, Jesus Pastormedrano, Fernando Urenanunez, Jaime Floresestrada, Telesforo Jesus MoralesjuarezAbstract:Zn(II), Cd(II) and Hg(II) ϵ-caprolactam-3-Dithiocarboxylic Acid complexes were synthesized by reacting the ϵ-caprolactam-3-carbothioic sodium salt with the respective metal salt. Samples were characterized by X-ray powder diffraction, EDS elemental analysis, UV-visible, FT-IR, 1H NMR and EPR spectroscopy. Thermal properties were determined using thermogravimetry and differential scanning calorimetric analysis. M-ϵ-caprolactam-3-Dithiocarboxylic Acid complexes showed intense electronic delocalization due to the charge transfer (420 nm) induced from the metal to the dithiolate group reaching different stages into the V unit (350 nm) of the dithiocarboxylate ring with a “n → π” (310 nm) transition. This transition was also observed by EPR which showed 3 parallel and 3 perpendicular signals. The complexes are stabilized by the electro-attraction of the amidic and carbonyl groups; the stability trend is Zn > Cd > Hg. Thermal decomposition shows a multi-step fragmentation process that suggests lactamic chain ru...
Y Coulais - One of the best experts on this subject based on the ideXlab platform.
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synthesis and biodistribution of new oxo and nitrido 99mtc complexes with asymmetrical potentially dianionic or trianionic tetradentate snno ligands derived from methyl 2 aminocyclopentene 1 Dithiocarboxylic Acid
Nuclear Medicine and Biology, 1998Co-Authors: Hafid Belhadjtahar, G Cros, M H Darbieu, J A M Tafani, J Fabre, J P Esquerre, E Ouhayoun, Y CoulaisAbstract:In this work, 10 new asymmetrical tetradentate SNNO ligands were prepared by reaction of the amine function of methyl 2-[(beta-aminoethyl)amino]cyclopentene-1-dithiocarboxylate with various bifunctional substituents bearing hydroxyl/ketone and hydroxyl/aldehyde functional groups and with diethyl oxalate. 99mTc labeling efficiency was optimized by adjusting temperature and pH conditions. Seven nitrido and two oxo 99mTc complexes were isolated. Six of them proved to be stable near physiological conditions. Biodistribution studies in the rat showed a significant heart uptake for four of them and strong kidney and liver uptake for the other two.
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technetium labeling of bi tri and tetradentate ligands derived from 2 aminocyclopentene 1 Dithiocarboxylic Acid characterization and biodistribution of their oxo and nitrido 99mtechnetium complexes
Nuclear Medicine and Biology, 1996Co-Authors: Hafid Belhadjtahar, Y Coulais, G Cros, M H Darbieu, J A M Tafani, J Fabre, J P Esquerre, R GuiraudAbstract:Abstract We have synthesized and characterized seven ligands derived from 2-aminocyclopentene-1-Dithiocarboxylic Acid with different donor sets (SN 2− , SNO 2− , SNN 2− , SNNO 3− and SNNN 3− ) and different substituents on the sulfur moieties -SR (with R=H, CH 3 or C 2 H 5 O(CH 3 )CH). With five of these ligands technetium nitrido complexes have been obtained with high yields (over 95%) using rather harsh conditions (pH ≈ 1, temperature ≥ 80 °C), whereas for technetium oxo complexes similar high yields were only obtained with two ligands but with mild conditions (pH = 7–8, temperature ≈ 50 °C). Changing an OH group for an NH 2 has a drastic effect upon labeling yields. The possibility of complexing ligands as either oxo (TcO) 3+ or nitrido (TcN) 2+ derivatives increases the number of available labeled agents with different overall change and consequently with different biological behavior.
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synthesis characterization and biodistribution of new 99mtc oxo and nitrido complexes with bi and tetradendate unsaturated ns and n2s2 schiff bases derived from 2 aminocyclopentene 1 Dithiocarboxylic Acid as potential heart imaging agents
Nuclear Medicine and Biology, 1994Co-Authors: Y Coulais, Hafid Belhadjtahar, G Cros, M H Darbieu, J A M Tafani, E Bellande, R Pasqualini, R GuiraudAbstract:Abstract The synthesis, characterization and 99m Tc labelling of unsaturated diamino dithiol ligands with methyl dithiocarboxylate functions: 2-aminocyclopentene-1-Dithiocarboxylic methyl ester (H 2 L1), N,N′ -ethylene bis (methyl 2-aminocyclopentene-1-dithiocarboxylate) (H 2 L 2 ) and N,N′ -propylene bis (methyl 2-aminocyclopentene-1-dithiocarboxylate) (H 2 L3) are described. Cationic oxo (TcO) and neutral nitrido (TcN) complexes were obtained. Biodistribution studies in rat showed a good heart uptake of 99m TcN-L2 (2% ID at 5 min) with a high heart-to-blood ratio (5.8 at 5 min), but this complex also exhibited high lung and liver uptake.
Hafid Belhadjtahar - One of the best experts on this subject based on the ideXlab platform.
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synthesis and biodistribution of new oxo and nitrido 99mtc complexes with asymmetrical potentially dianionic or trianionic tetradentate snno ligands derived from methyl 2 aminocyclopentene 1 Dithiocarboxylic Acid
Nuclear Medicine and Biology, 1998Co-Authors: Hafid Belhadjtahar, G Cros, M H Darbieu, J A M Tafani, J Fabre, J P Esquerre, E Ouhayoun, Y CoulaisAbstract:In this work, 10 new asymmetrical tetradentate SNNO ligands were prepared by reaction of the amine function of methyl 2-[(beta-aminoethyl)amino]cyclopentene-1-dithiocarboxylate with various bifunctional substituents bearing hydroxyl/ketone and hydroxyl/aldehyde functional groups and with diethyl oxalate. 99mTc labeling efficiency was optimized by adjusting temperature and pH conditions. Seven nitrido and two oxo 99mTc complexes were isolated. Six of them proved to be stable near physiological conditions. Biodistribution studies in the rat showed a significant heart uptake for four of them and strong kidney and liver uptake for the other two.
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technetium labeling of bi tri and tetradentate ligands derived from 2 aminocyclopentene 1 Dithiocarboxylic Acid characterization and biodistribution of their oxo and nitrido 99mtechnetium complexes
Nuclear Medicine and Biology, 1996Co-Authors: Hafid Belhadjtahar, Y Coulais, G Cros, M H Darbieu, J A M Tafani, J Fabre, J P Esquerre, R GuiraudAbstract:Abstract We have synthesized and characterized seven ligands derived from 2-aminocyclopentene-1-Dithiocarboxylic Acid with different donor sets (SN 2− , SNO 2− , SNN 2− , SNNO 3− and SNNN 3− ) and different substituents on the sulfur moieties -SR (with R=H, CH 3 or C 2 H 5 O(CH 3 )CH). With five of these ligands technetium nitrido complexes have been obtained with high yields (over 95%) using rather harsh conditions (pH ≈ 1, temperature ≥ 80 °C), whereas for technetium oxo complexes similar high yields were only obtained with two ligands but with mild conditions (pH = 7–8, temperature ≈ 50 °C). Changing an OH group for an NH 2 has a drastic effect upon labeling yields. The possibility of complexing ligands as either oxo (TcO) 3+ or nitrido (TcN) 2+ derivatives increases the number of available labeled agents with different overall change and consequently with different biological behavior.
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synthesis characterization and biodistribution of new 99mtc oxo and nitrido complexes with bi and tetradendate unsaturated ns and n2s2 schiff bases derived from 2 aminocyclopentene 1 Dithiocarboxylic Acid as potential heart imaging agents
Nuclear Medicine and Biology, 1994Co-Authors: Y Coulais, Hafid Belhadjtahar, G Cros, M H Darbieu, J A M Tafani, E Bellande, R Pasqualini, R GuiraudAbstract:Abstract The synthesis, characterization and 99m Tc labelling of unsaturated diamino dithiol ligands with methyl dithiocarboxylate functions: 2-aminocyclopentene-1-Dithiocarboxylic methyl ester (H 2 L1), N,N′ -ethylene bis (methyl 2-aminocyclopentene-1-dithiocarboxylate) (H 2 L 2 ) and N,N′ -propylene bis (methyl 2-aminocyclopentene-1-dithiocarboxylate) (H 2 L3) are described. Cationic oxo (TcO) and neutral nitrido (TcN) complexes were obtained. Biodistribution studies in rat showed a good heart uptake of 99m TcN-L2 (2% ID at 5 min) with a high heart-to-blood ratio (5.8 at 5 min), but this complex also exhibited high lung and liver uptake.