Fatemeh Sabermahani; Fatemeh Ziaaddini; Zahra Hassani
Volume 3, Issue 2 , September 2016, , Pages 137-144
Abstract
Removal of Pb(II) and Zn(II) ions from aqueous solutions using naphthalene modified with 2-(3,4,5-trimethoxybenzylidene) malononitrile(TMBM) as synthetic adsorbent was investigated. It was characterized by FT-IR. Batch method was applied for testing of adsorption behavior. Adsorption experiments showed, ...
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Removal of Pb(II) and Zn(II) ions from aqueous solutions using naphthalene modified with 2-(3,4,5-trimethoxybenzylidene) malononitrile(TMBM) as synthetic adsorbent was investigated. It was characterized by FT-IR. Batch method was applied for testing of adsorption behavior. Adsorption experiments showed, the new sorbent has high selectivity and good adsorption for removal of lead and zinc ions from aqueous solutions. Equilibration time was 5 min for zinc and 15 min for lead. There was little effect of salt on removal of the ions. The maximum adsorption capacities for Pb(II) and Zn(II) were 88.5 and 38.9 mg g-1, respectively. The thermodynamic studies indicated that the adsorption was spontaneous, exothermic and endothermic process for lead and zinc, respectively.
Mohammad Reza Jamali; Aysanam Kazemi
Volume 1, Issue 1 , March 2014, , Pages 36-43
Abstract
A simple, selective and efficient solid phase extraction method based on the use of γ-alumina nanoparticles coated with sodium dodecyl sulfate (SDS) and modified with 2-(5-Bromo-2-pyridylazo)-5-(diethylamino) phenol (5-Br-PADAP) as a new adsorbent was developed for ...
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A simple, selective and efficient solid phase extraction method based on the use of γ-alumina nanoparticles coated with sodium dodecyl sulfate (SDS) and modified with 2-(5-Bromo-2-pyridylazo)-5-(diethylamino) phenol (5-Br-PADAP) as a new adsorbent was developed for the separation and preconcentration of trace amounts of manganese (II) prior to determination by flame atomic absorption spectrometry. Analytical influencing parameters including pH value, amount of modified sorbent, equilibrium time, volume and concentration of eluent were examined. Under the optimum conditions, adsorption capacity of nano- Al2O3-SDS-5-Br-PADAP, enrichment factor and limit of detection for manganese (II) was 18.5 mg g -1, 25 and 0.9 µg L -1, respectively. The procedure was successfully applied to the determination of manganese (II) in water and milk samples.
Popat Baban Mohite; Shantaram Gajanan Khanage; Sandip Shankar Jadhav
Volume 2, Issue 1 , March 2015, , Pages 57-62
Abstract
Eperisone Hydrochloride is a skeletal muscle relaxant and Paracetamol is cyclooxygenase inhibitor. These drugs in combination are used as antispasmodics. A simple, specific, precise and accurate method was developed, namely reverse phase high performance liquid chromatography for simultaneous estimation ...
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Eperisone Hydrochloride is a skeletal muscle relaxant and Paracetamol is cyclooxygenase inhibitor. These drugs in combination are used as antispasmodics. A simple, specific, precise and accurate method was developed, namely reverse phase high performance liquid chromatography for simultaneous estimation of Eperisone Hydrochloride and Paracetamol in tablet dosage form. In RP-HPLC method separation was achieved by HiQ silC-18HS column having 250 mm× 4.6 mm, with mobile phase containing Methanol: 0.05 mM Ammonium acetate buffer: Acetonitrile (60:30:10) and adjusted to pH 5.8 using Glacial acetic acid for RP-HPLC system. The flow rate was 1.0 ml/min and effluent was monitored at 264 nm. The retention time of EPR and PAR were 6.45 min and 3.05 min respectively. The linearity for EPR and PAR were in the range of 5-25 µg/mL. The recoveries of EPR and PAR were found in the range of 99.96-100.52% and 99.87-100.11%, respectively. The proposed method was validated as per ICH guidelines and successfully applied to the estimation of EPR and PAR in tablet dosage form.
Zahra Monsef Khoshhesab; Mohammadreza Mohammadi Pour Salehloo
Abstract
In this work, Zinc oxide nanoparticles (ZnONPs) were utilized as a potential adsorbent for the adsorption of Reactive Blue 25 (RB25) and Reactive Blue 49 (RB49) dyes from aqueous solutions. ZnONPs adsorbent was synthesized by precipitation method and characterized using XRD, TEM, SEM, and N2 adsorption ...
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In this work, Zinc oxide nanoparticles (ZnONPs) were utilized as a potential adsorbent for the adsorption of Reactive Blue 25 (RB25) and Reactive Blue 49 (RB49) dyes from aqueous solutions. ZnONPs adsorbent was synthesized by precipitation method and characterized using XRD, TEM, SEM, and N2 adsorption /desorption techniques. The effect of various parameters including solution pH, shaking time, adsorbent amount and initial concentration of the dyes on the adsorption efficiency was studied. The experimental adsorption data analyzed with various kinetic and isothermal methods. The adsorption kinetic study revealed that the adsorption process followed pseudo-second-order kinetic model. Additionally, adsorption isotherm studies indicated that adsorption equilibrium data were well fitted to Langmuir model and accordingly, the maximum adsorption capacity of the adsorbent for RB25 and RB49 found to be 34.36 and 34.60 (mg/g), respectively. From this study, ZnONPs is suggested as an effectual adsorbent for the removal of dyes from aqueous samples.
Nosrat Madadi Mahani; Khadije Anjomshoaa; Sayed Zia Mohammadi
Abstract
N-salicyloyl tryptamine derivatives as anti-neuroinflammatory agents have a potent strategy to cure neuroinflammatory diseases including Alzheimer and Parkinson. Computational methods of quantitative structure properties relationships (QSPR) and molecular dynamics were successfully used to design of ...
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N-salicyloyl tryptamine derivatives as anti-neuroinflammatory agents have a potent strategy to cure neuroinflammatory diseases including Alzheimer and Parkinson. Computational methods of quantitative structure properties relationships (QSPR) and molecular dynamics were successfully used to design of four novel N-salicyloyl tryptamine with improved properties. The QSPR model of five variables was presented to predict anti- neuroinflammatory activity of N-salicyloyl tryptamine derivatives. The quantum descriptors as Hartree Fock energy, ionization energy, softness, dipole moment and the thermal energy, were calculated with density functional theory at the B3LYP/6-311G level. Cross validation of multivariate linear regression (MLR) was used to build and evaluate the model QSPR. The model possesses coefficients of the highest squared correlation coefficient (R2) of 0.900 for the training set and 0.817 for the test set. The statistical results exhibited high internal and external consistency as demonstrated by the validation methods. Three of designed compounds showed good pharmacokinetic properties by QSPR predictions. These results provided strong guidance for the discovery and design of novel potential anti- neuroinflammatory compounds. Also, the adsorption of the designed compounds on functionalized carbon nanotube (8, 0) was investigated using molecular dynamics simulation with COMPASS force field. Results indicated that the adsorption of designed N-salicyloyl tryptamine derivatives on f-CNT involves a partial π–π interaction and hydrogen bonding. The study of investigation the interactions of N-salicyloyl tryptamine with f-CNT (8, 0) can be useful for finding the main CNT-based carriers for these derrivatives.
Mohammad Reza Hadjmohammadi; Maede Asadi
Volume 1, Issue 2 , September 2014, , Pages 65-71
Abstract
The applicability of hollow fiber-based liquid phase microextraction (HF-LPME) was evaluated for the extraction and preconcentration of Loratadine prior to determination by HPLC. In order to obtain high extraction recovery, the parameters affecting the HF-LPME including type of organic phase, pH of the ...
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The applicability of hollow fiber-based liquid phase microextraction (HF-LPME) was evaluated for the extraction and preconcentration of Loratadine prior to determination by HPLC. In order to obtain high extraction recovery, the parameters affecting the HF-LPME including type of organic phase, pH of the source and receiving phases, stirring rate, extraction time and salt addition were studied and optimized. Under the optimized conditions, enrichment factor of 308 with relative standard deviation (R.S.D.%) equel 3.8% were achieved. The calibration curve was linear in the range of 0.3–600 ng/ml with good linearity (R2 = 0.9991). The limit of detection (LOD) was 0.1 ng/ml (based on S/N = 3). Finally, determination of Loratadine in human plasma was used by HF-LPME-HPLC and indicated that this method had an excellent clean-up and high recovery factor (84%) for Loratadine.
Mahmood Payehghadr; Seied Ebrahim Hashemi; Zarin Eshaghi; Hadi Kargar
Abstract
The complexation reactions between N-N′-Bis(5-bromo-2-hydroxybenzylidene)-2,2-dimethylpropane-1,3-diamine Schiff base ligand and Ag+, Cd2+, Co2+, Cu2+, Hg2+, Ni2+, and Zn2+ ions were studied conductometrically in acetonitrile, dimethylformamide, ethanol, and methanol solvents at 5, 10, 15, and ...
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The complexation reactions between N-N′-Bis(5-bromo-2-hydroxybenzylidene)-2,2-dimethylpropane-1,3-diamine Schiff base ligand and Ag+, Cd2+, Co2+, Cu2+, Hg2+, Ni2+, and Zn2+ ions were studied conductometrically in acetonitrile, dimethylformamide, ethanol, and methanol solvents at 5, 10, 15, and 25ºC. The formation constants of the resulting ML and M2L complexes were calculated from the computer fitting of the molar conductance-mole ratio data at different temperatures. The selectivity of the Schiff base ligand to the cations is depended the nature of the solvent. At 25ºC in acetonitrile solvent, the stability of the resulting complexes varied in the order Hg2+ > Ag+ > Cd2+ > Cu2+ > Co2+ > Zn2+ > Ni2+. It was found that the stability of the resulting complexes decreased with increasing the solvation ability of the solvent. The values of the thermodynamic parameters (ΔH°, ΔS° and ΔG°) for complexation reactions were obtained from the temperature dependence of the stability constants values (log Kf) using the Van’t Hoff plots. In most cases, the complexes were found to be an enthalpy and entropy stabilized.
Hadieh Habibagahi; Ali Sheibani; M. Reza Shishehbore
Volume 3, Issue 1 , March 2016, , Pages 70-75
Abstract
In this study, a third derivative spectrophotometric method based on zero-crossing technique is developed for the simultaneous determination of atenolol and propranolol. Effective parameters including temperature and pH were investigated and optimized. Under optimum experimental conditions (temperature: ...
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In this study, a third derivative spectrophotometric method based on zero-crossing technique is developed for the simultaneous determination of atenolol and propranolol. Effective parameters including temperature and pH were investigated and optimized. Under optimum experimental conditions (temperature: 10 oC and pH: 8-10), calibration curves were linear between concentration ranges of 0.8 to 12.9 μg mL-1 of atenolol and 0.3 to 6.4 μg mL-1 of propranolol. The limit of detection was 0.2 μg mL-1 and relative standard deviation was lower than 3%. The proposed method was applied for the simultaneous determination of both drugs in the pharmaceutical formulations. Acceptable recoveries of the analytes, ranging from 97 to 107%, were obtained.
Hassan Karami; Bahr Ali Najafi
Volume 2, Issue 2 , September 2015, , Pages 127-137
Abstract
Hydrous manganese dioxide nanoclusters are prepared by the oxidation of manganese (II) ions with ammonium persulfate and used as a new sorbent for Ag+ ion removal from aqueous medium. The synthesized compound is characterized using scanning electron microscopy, dynamic light scattering, energy dispersive ...
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Hydrous manganese dioxide nanoclusters are prepared by the oxidation of manganese (II) ions with ammonium persulfate and used as a new sorbent for Ag+ ion removal from aqueous medium. The synthesized compound is characterized using scanning electron microscopy, dynamic light scattering, energy dispersive analysis of X-rays, X-ray diffraction and BET surface measurements. Scanning electron microscopy images showed that the synthesized Hydrous manganese dioxide nanoclusters include cactus-shaped nanoclusters with uniform needles of average diameter of 36 nm and length of 1000 nm. X-ray diffraction data reveal that γ-MnO2 is formed in this method. Batch experiments are carried out to evaluate the Ag+ adsorption capacity of Hydrous manganese dioxide nanoclusters. The maximum adsorption capacity estimated by the Langmuir model was 81.97 mg g-1 for Ag+. Silver ion adsorption on Hydrous manganese dioxide nanoclusters is a fast process and the kinetics followed a pseudo-second-order rate equation. The removal efficiency of Ag+ depends on Hydrous manganese dioxide nanoclusters amount, pH and temperature of the solution. The presences of Na+, Ca2+ and Mg2+ ions in the concentrations lower than 200 ppm have no significant influence on silver ion removal. The adsorbed ions can easily eluted by the small volume of a solution consisting thiourea and hydrochloric acid. Finally, the experimental data show that the synthesized Hydrous manganese dioxide nanoclusters can quantitatively remove silver ions from real water samples.
Habibollah Khajehsharifi; Aida Solhjoo; Mohammad Mahdi Bordbar
Volume 3, Issue 2 , September 2016, , Pages 145-152
Abstract
A selective optical sensor based on immobilization of Eriochrome Cyanine R for the determination of Al(III) ions in aqueous solution has been developed. The method is based on the spectrophotometric measurement of complex Eriochrome Cyanine R-aluminium at 537 nm. The sensing membrane is made of a triacetylcellulose ...
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A selective optical sensor based on immobilization of Eriochrome Cyanine R for the determination of Al(III) ions in aqueous solution has been developed. The method is based on the spectrophotometric measurement of complex Eriochrome Cyanine R-aluminium at 537 nm. The sensing membrane is made of a triacetylcellulose film containing Eriochrome Cyanine R colorimetric reagent immobilized as an ion pair with methyltrioctylammonium chloride. The response of the sensor is based on the Eriochrome Cyanine R absorbance decrease by the coordination of Al(III) ions. At pH= 6.0, the linear dynamic rangeis varied from 3.22×10-8 to 4.10×10-5 mol L-1 with a detection limit of 1.2× 10-8 mol L-1. A dynamic working range, detection limit, sensitivity, selectivity and the response time were discussed in detail. The response was pH dependent. The membrane responds to Al(III) ions irreversibly by changing color from pink to blue. The membrane was regenerated in less than 30 seconds with 0.1 mol L-1 EDTA solution and was ready for further measurements. The response time of the sensor was within 16 min depending on the concentration of Al (III) ions. The sensor response was found to have a repeatability and reproducibility of 1.62% and 3%, respectively. The sensor provides appropriate selectivity to Al(III) ions over transition metal cations, including Co(II), Ni(II), Fe(III), Cu(II) and Zn(II). The sensor has been used for the determination of Al(III) ions in potable water and aluminium – magnesium syrup.
Foroozan Hasanpour; Zahra Alimirzaei; Masoumeh Taei; Hamed Karimi; R. Samimi
Volume 1, Issue 1 , March 2014, , Pages 44-49
Abstract
Cloud point extraction and spectrophotometric determination of trace quantities of cadmium in some vegetables have been developed. The research area for vegetables analysis was near to the Zarin Shahr where the soil received heavy metals from the Esfahan Steel Company. Cloud point extraction used dithizone ...
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Cloud point extraction and spectrophotometric determination of trace quantities of cadmium in some vegetables have been developed. The research area for vegetables analysis was near to the Zarin Shahr where the soil received heavy metals from the Esfahan Steel Company. Cloud point extraction used dithizone as complexing agent and non ionic surfactant Triton-X114 as micellar phase. Several important variables affecting the separation and determination process were optimized. Under optimized conditions calibration graph was linear in the range of 1.0-180 ng mL-1 with detection limit of 0.2 ng mL-1. Preconcentration of 10 mL of samples gave an enhancement factor of 50. The proposed method was applied for determination of Cd(II) in vegetable samples with satisfactory results.
Bakhtiar Khodavirdilo; Naser Samadi; Marzieh Ahari Salmasi
Abstract
In this study a new method by using graphene oxide (GO) Nano sheets-melamine composites and derivation of Poly (Styrene –alternative- Maleic Anhydride) (SMA), (SMA+Melamine) (SMA-M) were presented as Sorbents for the elimination of Lead ions from aqueous solutions. The adsorbents have the sufficiency ...
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In this study a new method by using graphene oxide (GO) Nano sheets-melamine composites and derivation of Poly (Styrene –alternative- Maleic Anhydride) (SMA), (SMA+Melamine) (SMA-M) were presented as Sorbents for the elimination of Lead ions from aqueous solutions. The adsorbents have the sufficiency to adsorb the Lead ions. Through the immobilization of melamine onto GO Nano sheets, the desired composite was synthesized and identified by field emission scanning electron microscopy (FE-SEM), Fourier transform infrared (FT-IR) spectroscopy and absorption atomic spectroscopy (AAS) techniques. The various experimental parameters such as pH and concentration of the aqueous solution of Lead (II) ion, the content of the Lead (II) ion the grapheme oxide-Melamine and SMA-M have been optimized. It was shown that the uptake efficiency of Lead (II) ion considerably increased after immobilization of Melamine on the GO Nano sheets and SMA.
Maryam Malekzadeh; Faeze Daneshfar; Seyed Mohsen Sadeghzadeh
Volume 1, Issue 2 , September 2014, , Pages 72-77
Abstract
Nano SiO2/hyperbranched polyglycerol (HPG)/SO3H catalyst was readily prepared for first time from inexpensive starting materials in aqueous media which catalyzed the synthesis of benzoic acid. FTIR spectra, X-ray diffraction (XRD) and transmission electron micrographs (TEM) was employed to characterize ...
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Nano SiO2/hyperbranched polyglycerol (HPG)/SO3H catalyst was readily prepared for first time from inexpensive starting materials in aqueous media which catalyzed the synthesis of benzoic acid. FTIR spectra, X-ray diffraction (XRD) and transmission electron micrographs (TEM) was employed to characterize the properties of the synthesized nano SiO2/HPG/SO3H. High catalytic activity and ease of recovery from the reaction mixture using filtration and several reuse times without significant losses in performance are additional eco-friendly attributes of this catalytic system.
Hossein Tavallali; Gohar Deilamy-Rad; Mohammad Ali Karimi; Elaheh Sharifi; Zahra Tavallali; Arshida Najafi-Nejad
Abstract
Bromopyrogallol Red (BPR) dye (Dibromopyrogallolsulfonphthalein), was evaluated as a highly selective colorimetric chemosensor for tin and citrate ion. BPR displayed rapid response, high specificity, visual determination and good selectivity toward tin and citrate ion over other competing cations and ...
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Bromopyrogallol Red (BPR) dye (Dibromopyrogallolsulfonphthalein), was evaluated as a highly selective colorimetric chemosensor for tin and citrate ion. BPR displayed rapid response, high specificity, visual determination and good selectivity toward tin and citrate ion over other competing cations and anions in DMSO/H2O (1:1 v/v) media. The sensing mechanism was discussed by UV–Vis, titration, and a comparison study. Over a wide range from 0.4 µmol L-1 to 153.8 µmol L-1 and 0.02 µmol L-1 to 1.08 µmol L-1, a good linear relationship between the absorbance and the concentration of tin and citrate ion was found respectively and the detection limit was estimated to be as low as 0.06 and 0.003 µmol L-1 (S/N = 3) for tin and citrate ion. This proposed chemosensor has also been successfully applied for the determination of citrate in real samples which demonstrates its value of practical applications in food and biological systems.
Nagaraj P Shetty; Gopalakrishna Bhatn; Chandrashekara Kg
Volume 1, Issue 1 , March 2014, , Pages 50-52
Abstract
A complexometric method for the determination of titanium in the presence of other metal ions based on the selective masking ability of 5-sulphosalicylic acid towards titanium is described. Titanium (IV) present in a given sample solution is complexed with a known excess of EDTA and surplus EDTA is titrated ...
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A complexometric method for the determination of titanium in the presence of other metal ions based on the selective masking ability of 5-sulphosalicylic acid towards titanium is described. Titanium (IV) present in a given sample solution is complexed with a known excess of EDTA and surplus EDTA is titrated against zinc sulphate solution at pH 5-6 using xylenol orange as the indicator. A known excess of 10% solution of 5-sulphosalicylic acid is then added. The mixture is then shaken well and the EDTA released from Ti-EDTA complex is titrated against the standard zinc sulphate solution. Reproducible and accurate results are obtained for 0.96 – 28.75 mg of titanium (IV) with relative error ± 0.17% and standard deviations ≤ 0.02 mg. The interference of various ions is studied. This method was applied to the determination of titanium (IV) in its alloys.
Sedigheh Kamran; Hossein Tavallali; Ali Azad
Volume 1, Issue 2 , September 2014, , Pages 78-86
Abstract
Fe3O4 magnetic nanoparticles modified with 1-Octyl-3-methylimidazolium bromide([C8MIM]-Fe3O4) were used for the removal of reactive red 141 (RR141) and reactive yellow 81 (RY81) as model azo dyes from aqueous solution. The mean size and the surface morphology of the nanoparticles were characterized by ...
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Fe3O4 magnetic nanoparticles modified with 1-Octyl-3-methylimidazolium bromide([C8MIM]-Fe3O4) were used for the removal of reactive red 141 (RR141) and reactive yellow 81 (RY81) as model azo dyes from aqueous solution. The mean size and the surface morphology of the nanoparticles were characterized by TEM, XRD and FTIR techniques. Adsorption studies of two dyes were performed under different experimental conditions in batch technique. The adsorption of dyes onto [C8MIM]-Fe3O4 nanoparticles was affected by the initial pH, dye concentration, adsorbent amount, contact time and temperature. Experimental results indicated that [C8MIM]-Fe3O4 nanoparticles removed more than 98%. The maximum adsorption capacity of [C8MIM]-Fe3O4 for the Langmuir model was 71.4 mg g−1 and 62.5 mg g−1 for RR141 and RY81, respectively. The isotherm evaluations revealed that the Langmuir model attained better fits to the equilibrium data than the Freundlich model. Adsorption processes onto [C8MIM]-Fe3O4 nanoparticles were spontaneous exothermic and endothermic for RY81 and RR141, respectively. Dyes were desorbed from nanoparticlesby NaCl solution 0.1 mol L−1 at 80 and 30 °C for RR141 and RY81, respectively.
Tahereh Rohani; Sayed Zia Mohammadi; Amirkhosro Beheshti; Hooshang Hamidian; Nasrin Gholamhosein Zadeh
Abstract
Herein, the electrooxidation of ascorbic acid and folic acid, as two essential vitamins, on the surface of the carbon ceramic electrode modified by polydopamine and copper (Cu/PDA/CCE) was investigated. Poly dopamine was fabricated by applying electro deposition conditions. Initial electrochemical characteristics ...
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Herein, the electrooxidation of ascorbic acid and folic acid, as two essential vitamins, on the surface of the carbon ceramic electrode modified by polydopamine and copper (Cu/PDA/CCE) was investigated. Poly dopamine was fabricated by applying electro deposition conditions. Initial electrochemical characteristics were performed to study the behavior of the fabricated electrode for simultaneous detection of two biomolecules. From voltametric studies using the developed electrode, two separated anodic peaks for folic acid and ascorbic acid were found promisingly for concurrent detection of the compounds. Linear calibration diagrams were obtained in the range of 0.5 to 360 μM and 0.83 to 380 μM with detection limits of about 0.031 and 0.057 μM for folic acid and ascorbic acid, respectively. The developed electrode was applied in human urine sample analysis with satisfying results
Maryam Ghanbarian; Farzad Etemadi; Ali Mostafavi; Moslem Afzali
Volume 1, Issue 1 , March 2014, , Pages 53-57
Abstract
In this work, a selective method for separation and preconcentration of nickel ions at trace level on modified multiwalled carbon nanotubes columns and determination by flame atomic absorption spectrometry (FAAS) has been developed. Multiwalled carbon nanotubes were oxidized with concentrated HNO3 and ...
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In this work, a selective method for separation and preconcentration of nickel ions at trace level on modified multiwalled carbon nanotubes columns and determination by flame atomic absorption spectrometry (FAAS) has been developed. Multiwalled carbon nanotubes were oxidized with concentrated HNO3 and then modified with loading 1-(2-pyridylazo)-2-naphtol. The sorption of Ni(II) ions was quantitative in the pH =9. Elution of the adsorbed nickel was carried out with 5.0 mL of 0.1 mol L−1 HNO3. The amount of eluted nickel was measured using flame atomic absorption spectrometry. Factors influencing sorption and desorption of Ni(II) ions were investigated, including the sample pH, flow rates of sample and eluent solution, eluent type, breakthrough volume and interference ions. The relative standard deviation of the method was ±0.57% (n=8) and the limit of detection was 2.04 g mL−1 (3σb/m, n=8). The method was applied to the determination of Ni(II) in water samples and standard alloy (NKK. NO. 920, Aluminum Alloy).
Sayyed Hossein Hashemi; Massoud Kaykhaii; Mohamad Shakeri
Abstract
In this research, a new modeling method based on three-layer artificial neural network (ANN) technique was applied to predict the extraction yield of copper-morin complex from aqueous samples by means of molecularly imprinted stir bar sorptive extraction. Input variables of the model were pH of the solution, ...
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In this research, a new modeling method based on three-layer artificial neural network (ANN) technique was applied to predict the extraction yield of copper-morin complex from aqueous samples by means of molecularly imprinted stir bar sorptive extraction. Input variables of the model were pH of the solution, absorption and desorption times, stirring rate, temperature, and amount of morin ligand; while the output was extraction yield of copper ions. It was found that a network with 12 hidden neurons is highly accurate in predicting extraction recovery of copper-morin complex. The mean squared error and correlation coefficient between the experimental data and the ANN predictions were achieved as 0.0009 and 0.9999 for training, 0.0032 and 0.976 for validation and 0.0030 and 0.96666 for testing data sets. Under the optimum conditions, the linear range found to be in the range of 5-1000 μg L-1 with the detection limit of 0.38 μg L-1. The relative standard deviation was obtained to be below 5.3%. The method was successfully applied for preconcentration and determination of Cu in a few real samples.
Hossein Tavallali; Gohar Deilamy-Rad; Hoda Ansari
Volume 1, Issue 2 , September 2014, , Pages 87-96
Abstract
A novel magnetic mixed hemimicell solid phase extraction (MMHSPE) technique for speciation analysis of soluble, ferrous and ferric iron in legumes sample by flame atomic absorption spectrometry analysis (FAAS) was developed. MMHSPE system consisting of alumina-coated magnetite nanoparticles (Fe3O4/Al2O3NPs) ...
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A novel magnetic mixed hemimicell solid phase extraction (MMHSPE) technique for speciation analysis of soluble, ferrous and ferric iron in legumes sample by flame atomic absorption spectrometry analysis (FAAS) was developed. MMHSPE system consisting of alumina-coated magnetite nanoparticles (Fe3O4/Al2O3NPs) modified by sodium dodecylsulfate-1-(2-pyridylazo)-2-naphthol (SDS-PAN) have been successfully synthesized as an extracting agent. The procedure is based on complexation of Fe(II) with PAN that immobilized on the SDS-coated Fe3O4/Al2O3 NPs. Total iron is subjected to a similar extraction procedure after reduction. Then Fe(III) has been calculated by subtracting Fe(ΙI) from the total iron. The new and rapid method of analyses (MMHSPE technique) has been successfully applied for the determination of iron ions in certified reference materials (NCS DC 73349—bush, branches and leaves; and TM-23.2—fortified water) and legumes samples with high efficiency. Under the optimum conditions of parameters, the recoveries of Fe(ΙI) by analyzing the seven spiked some legumes samples were between 96.0% and 103.6% and detection limits of Fe(ΙI) were between 1.7 and 3.1 ng mg−1. The results have been also indicated that Fe3+ concentrations obtained are always higher than the Fe2+ contents in legumes sample and Soy bean snack and Peanut have the maximum content of Fe2+.
Sandeep Jaggi; Usha Gupta
Volume 1, Issue 2 , September 2014, , Pages 97-105
Abstract
A simple and sensitive method has been developed for the preconcentration and determination of trace level of Co(II) using UV-Vis spectrophotometry. β-Cyclodextrin polymer modified with 1-(2-pyridylazo)-2-naphthol (PAN) is used for the preconcentration of Co(II) from samples at pH 8.5. The polymer ...
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A simple and sensitive method has been developed for the preconcentration and determination of trace level of Co(II) using UV-Vis spectrophotometry. β-Cyclodextrin polymer modified with 1-(2-pyridylazo)-2-naphthol (PAN) is used for the preconcentration of Co(II) from samples at pH 8.5. The polymer is synthesized and characterized using elemental analysis, FT-IR and SEM analysis. The factors affecting the recovery of Co(II) such as pH, adsorbent dose, contact time, sample volume, eluent concentration and volume are also optimized in order to achieve higher sensitivity. The recoveries of Co(II) are found to be 95% and the relative standard deviation found by analyzing 3 replicates is ≤2.9. The preconcentration factor is found to be 100. The limit of detection (LOD) determined as (3σ) is found to be 4.2 ng/ml and limit of quantification (LOQ) determined as (10σ) is found to be 14 ng/ml. The recoveries achieved by addition of Co(II) at known concentrations to samples and analysis results show that the described method has a good accuracy. The proposed method is applied to water, vegetable and alloy samples successfully.
Reyhaneh Rahnama; Sorour Eram
Volume 1, Issue 2 , September 2014, , Pages 106-114
Abstract
A new method for the separation and preconcentration of trace amounts of cadmium in food and water samples by magnetic solid phase extraction (MSPE) with Fe3O4 magnetic nanoparticles (Fe3O4-MNPs) and its determination by flame atomic absorption spectrometry has been developed. For this purpose, Fe3O4-MNPs ...
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A new method for the separation and preconcentration of trace amounts of cadmium in food and water samples by magnetic solid phase extraction (MSPE) with Fe3O4 magnetic nanoparticles (Fe3O4-MNPs) and its determination by flame atomic absorption spectrometry has been developed. For this purpose, Fe3O4-MNPs were synthesized via chemical precipitation method. The extraction of cadmium ions from the aqueous solution was performed with dithizone (DTZ) as the chelating agent. The various parameters affecting the extraction and preconcentration of cadmium were investigated and optimized. In this method, the analyte ions were quantitatively adsorbed on Fe3O4-MNPs and then, Fe3O4-MNPs were easily separated from the aqueous solution by applying an external magnetic field. After extraction and collection of Fe3O4-MNPs, the analyte ions were eluted using 1.0 mol L-1 HNO3 in methanol. Under the optimal conditions, the calibration curve showed an excellent linearity in the concentration range of 0.3–24.0 µg L-1 and the limit of detection was 0.1 µg L-1 of cadmium. The developed method was successfully applied to the determination of cadmium in food and water samples. The results show that, magnetic nanoparticles can be used as a cheap and efficient adsorbent for the extraction and preconcentration of cadmium from real samples for Loratadine.
Soleyman Bahar; Bahare Babamiri
Volume 1, Issue 2 , September 2014, , Pages 115-120
Abstract
In this work, a procedure for preconcentration of cobalt using dispersive liquid–liquid microextraction (DLLME) with the reagent 1-Nitroso 2-naphtol as complexing reagent was developed. At pH 4, Co(II) was complexed with 1-nitroso 2-naphtol and extracted into the fine droplets formed when mixing ...
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In this work, a procedure for preconcentration of cobalt using dispersive liquid–liquid microextraction (DLLME) with the reagent 1-Nitroso 2-naphtol as complexing reagent was developed. At pH 4, Co(II) was complexed with 1-nitroso 2-naphtol and extracted into the fine droplets formed when mixing chloroform (extraction solvent), ethanol (disperser solvent) and the sample solution. After extraction, the phases are separated and cobalt ion was determined in the enriched phase by flame atomic absorption spectrometry (FAAS). Under the optimum conditions, the enrichment factor 57.22 was obtained. The detection limit of the method was 3.76 ng mL-1 and the relative standard deviation (RSD) for eight replicate mrasurements of 0.05 µg mL-1 Co (II) was 2.3 %. The results to the determination of Co(II) in environmental water samples (tap water, well water, mineral water), egg yolk and hair have demonstrated the applicability of the proposed method.
Mehdi Hosseini; Mousa Soleymani; Hossein Dashti Khavidaki
Abstract
A simple, new and low-cost design of Li-air battery was introduced. An effective synthesized nanocatalyst for modifiying of air cathode, filter paper as a simple separator and a conductive ionic liquid namely 1-Octyl-3-methyl imidazolium hexafluorophosphate abbreviated [Omim][PF6] as a non-aqueous and ...
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A simple, new and low-cost design of Li-air battery was introduced. An effective synthesized nanocatalyst for modifiying of air cathode, filter paper as a simple separator and a conductive ionic liquid namely 1-Octyl-3-methyl imidazolium hexafluorophosphate abbreviated [Omim][PF6] as a non-aqueous and green electrolyte in battery were used. The MnFe2O4 nanoparticles (NP-MnFe2O4) which consistingof transition metal-metal oxide components was synthesized in our labrature. High discharge capacity, non-flammability of electrolyte, high reversibility, long lifetime and low over potential were observed in electrochemical tests of the battery. Synthesized nanocatalyst was characterized using XRD, FTIR and SEM techniques. XRD results show that a nanocatalyst have a particle sizes of 16-28 nm that distributed on cathode uniformly and performance of battery was improved to more than 1000 cycles compared to battery without any catalyst. The discharge capacity at current density of 0.2 mA cm-2 and charge potential range of 2.0-4.2 V for battery with catalyst/green electrolyte and without catalyst/common organic electrolyte were 3391 and 1012 mAh g-1,respectively. Furthermore, the usage of an ionic liquid as electrolyte leads to the increase the safety and lifetime of battery. Because of used electrolyte have high boiling point amount (>350 Celcius), so if it released to the environment due to the destruction or life expires of battery, don’t seriously damage to the environment because it is not easily evaporated.
Khalilollah Taheri; Nahid Rahneshan
Volume 1, Issue 2 , September 2014, , Pages 121-125
Abstract
A number of researches have been performed in the field of elemental analysis of fruitsfrom different areas of Iran and there is a vast unstudied area in this field. In this study, seven mineral elements such as Na, K, Ca, Mg, Fe, Zn and Cu in the tree soil, citrus limunum juice of Gorgan and Iranshahr ...
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A number of researches have been performed in the field of elemental analysis of fruitsfrom different areas of Iran and there is a vast unstudied area in this field. In this study, seven mineral elements such as Na, K, Ca, Mg, Fe, Zn and Cu in the tree soil, citrus limunum juice of Gorgan and Iranshahr gardens and citrus limetta juice of Gorgan and Bandarabas gardens were determined by flame photometry and atomic absorption spectrometry methods using standard addition technique. The results showed that the concentration of K and Cu elements in the samples of fruits was higher and lower than other elements, respectively. The concentration of Na and K elements in the citrus limetta sample of Bandarabas was more than that of the Gorgan sample. The concentration of Fe and Mg elements in the citrus limunum sample of Gorgan was more than that of the Iranshahr sample. The measurments showed that the concentration of Ca and Zn elements in the tree soil samples of citrus limunum, was higher and lower than the other elements, respectively. Moreover, although the concentration of the Ca element in the soil sample of Gorgan was more than that of Iranshahr, the concentration of this element in the citrus limunum of Gorgan was less than that of Iranshahr, this is probably due to problems in the Ca absorption of the citrus limunum plant of Gorgan. The obtained information in this study can be useful for some patients in the preferred consumption of these kinds of fruits. In addition, the used methods are reliable and simple analytical procedures for the mineral element characterisation of citrus limunum and citrus limetta fruits.
