Zahra Garkani-Nejad; Marziyeh Poshteh-Shirani
Volume 3, Issue 2 , September 2016, , Pages 116-126
Abstract
A 2D image approach has been used to predict 13C NMR chemical shifts of β-naphthalene derivatives. In multivariate image analysis-Quantitative structure property relationship (MIA-QSPR) study, descriptors correlating with dependent variable are pixels (binaries) of 2D chemical structures; Variant ...
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A 2D image approach has been used to predict 13C NMR chemical shifts of β-naphthalene derivatives. In multivariate image analysis-Quantitative structure property relationship (MIA-QSPR) study, descriptors correlating with dependent variable are pixels (binaries) of 2D chemical structures; Variant pixels in the structures (substitutes) account to explained variance in the property (chemical shifts). A case study is carried out in order to predict 13C NMR chemical shifts of 10 carbon positions of 24 mono substituted β-naphthalenes. The resulted descriptors were subjected to principal component analysis (PCA) and the most significant principal components (PCs) were extracted. Then, MIA-QSPR modeling was done by means of principal component regression (PCR) and principal component –artificial neural network (PC-ANN) methods. A correlation ranking procedure is proposed here to select the most relevant set of PCs as inputs for PCR and PC-ANN modeling methods. Here, the 13C chemical shifts of studied compounds were predicted using density functional theory (DFT) calculations, too. The widely applied method of gauge included atomic orbital (GIAO) B3LYP/6-311++ G have been used. The performance of the GIAO was also compared with PCR and PC-ANN models. Results showed the superiority of the PC-ANN over GIAO and PCR models. Finally, 13C NMR chemical shifts of studied compounds were calculated using ChemDraw program.
Majid Haji Hosseini; Mohammad Reza Rezaei; Mohammad Rezaee; Peyman Asaadi; Khatereh Ashtari
Volume 1, Issue 1 , March 2014, , Pages 20-28
Abstract
This study propose a new analytical protocol for the determination of benzene, xylene, toluene and styrene in water samples using homogeneous liquid-liquid microextraction via flotation assistance (HLLME-FA) technique followed by gas chromatography-mass spectrometry (GC-MS). In this research, a special ...
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This study propose a new analytical protocol for the determination of benzene, xylene, toluene and styrene in water samples using homogeneous liquid-liquid microextraction via flotation assistance (HLLME-FA) technique followed by gas chromatography-mass spectrometry (GC-MS). In this research, a special extraction cell was designed to facilitate collection of the low-density solvent extraction. No centrifugation was required in this procedure. The water sample solution was added into the extraction cell which contained an appropriate mixture of extraction and homogeneous solvents. By using air flotation, the organic solvent was collected at the conical part of the designed cell. The effects of different variables on the efficiency of the extraction were studied simultaneously using experimental design. Response surface methodology was applied to investigation the optimum conditions of each variable. Using optimized variables in the extraction process, for all target analytes, the detection limits, the precisions and the linearity of the method were found in the range of 0.8-8.2 ng mL-1, 3.09-7.96% (RSD, n=4) and 1-100 ng mL-1, respectively. The headspace method was used for the accuracy of comparison. The performance of the method was evaluated for extraction and determination of analytes in water samples and satisfactory results were obtained (RSD ≤10.06 %).
Motahare Vakili Fathabadi; Hassan Hashemipour Rafsanjani; Firooze Danafar
Volume 5, Issue 1 , March 2018, , Pages 39-43
Abstract
Carbon nanofibers (CNFs) and carbon nanorods (CNRs) are synthesized using coal particles (
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Carbon nanofibers (CNFs) and carbon nanorods (CNRs) are synthesized using coal particles (
Muneeba Usmani; Sofia Ahmed; Muhammad Sheraz; Iqbal Ahmad
Volume 5, Issue 2 , September 2018, , Pages 39-55
Abstract
Amikacin (AM) belongs to the family of aminoglycoside antibiotics. It is a broad spectrum antibiotic, effective against both Gram-negative and Gram-positive bacterial infections. The chemical structure of AM consists of hydroxyl (OH), glucopyranosyl and amino (NH2) groups. However, the lack of ...
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Amikacin (AM) belongs to the family of aminoglycoside antibiotics. It is a broad spectrum antibiotic, effective against both Gram-negative and Gram-positive bacterial infections. The chemical structure of AM consists of hydroxyl (OH), glucopyranosyl and amino (NH2) groups. However, the lack of chromophore in the AM structure made it difficult to detect it in the UV-visible region (200–800 nm). Therefore, derivatization of AM is carried out to introduce a chromophore in its structure which helps in its detection in the UV-visible region. Several methods have been developed and reported for the determination of AM in pharmaceutical and biological samples. These methods include chromatographic techniques such as thin layer chromatography (TLC), liquid chromatography (LC), hydrophilic interaction liquid chromatography (HILC), high performance liquid chromatography (HPLC), ultra-high performance liquid chromatography (UHPLC), ion chromatography (IC); spectrometry such as UV-visible spectrometry, spectrofluorimetry, nuclear magnetic resonance (NMR) spectrometry, mass spectrometry (MS); chemiluminescence; Rayleigh scattering method; electrochemical methods such as polarography, cyclic voltammetry, amperometry; immunoassay and microbial assay. This review highlights the application of these methods in the analysis of AM in pharmaceutical and biological samples.
Eslam Pourbasheer; Maryam Kargar Moghadam; Alireza Banaei
Volume 4, Issue 1 , March 2017, , Pages 40-50
Abstract
A quantitative structure-activity relationship model has been created for forecasting the antagonist potency of benzyl tetrazole derivatives as human histamine receptors. Various kinds of molecular descriptors were used to represent different aspects of the molecular structures. In this method, the whole ...
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A quantitative structure-activity relationship model has been created for forecasting the antagonist potency of benzyl tetrazole derivatives as human histamine receptors. Various kinds of molecular descriptors were used to represent different aspects of the molecular structures. In this method, the whole data set for the compounds were divided into the training and test sets. The model of relationships between molecular descriptors and biological activity of molecules were created by using stepwise multiple linear regressions and a genetic algorithm. Comparison of the results obtained indicated the superiority of the genetic algorithm based multiple linear regression over the stepwise based multiple linear regression. The ultimate quantitative structure-activity relationship model (N =64, R2=0.808, F= 30.806, Q2adj= 0.782, Q2LOO = 0.751, Q2LGO=0.669) was fully approved using the leave-one-out cross-validation method, Fischer statistics (F), external test set and the Y-randomization test. As a result, the produced quantitative structure-activity relationship model could be applied as a valorous instrumentation for sketching analogous groups of new antagonists of histamine receptors.
Ghasem Karim-Nezhad; Sara Pashazadeh; Samira Honarmand
Abstract
In this study, a novel and convenient electrochemical sensor was fabricated by using dripping well-dispersed graphene oxide nanosheets, electropolymerization of poly glycine (p-Gly) and in situ plating of metallic copper nanoparticle film methods, successively. This sensor was further employed to investigate ...
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In this study, a novel and convenient electrochemical sensor was fabricated by using dripping well-dispersed graphene oxide nanosheets, electropolymerization of poly glycine (p-Gly) and in situ plating of metallic copper nanoparticle film methods, successively. This sensor was further employed to investigate the electrochemical behavior of hydrazine. Scanning electron microscopy and energy dispersive X-ray spectrometry were used for the characterization of the prepared film. Anodic peak potential of hydrazine oxidation at the surface of modified electrode shifts by about 150 mV toward negative values compared with that on the bare electrode. The kinetic parameters such as the electron transfer coefficient (α) and charge transfer rate constant (k) for the oxidation of hydrazine was determined utilizing cyclic voltammetry (CV). The diffusion coefficient (D) of hydrazine was also estimated using chronoamperometry. The dynamic detection range of this sensor to hydrazine was 5- 60 and 80- 150 µM at the modified electrode surface using an amperometric method. The detection limit and quantitation are 5.33 µM and 17.77 µM, respectively. A new voltammetric method for determination of hydrazine was erected and shows good sensitivity and selectivity, wider linear relationship, very easy surface update and good stability.
Fereshteh Heydari; Majid Ramezani; Nasim Bayat; Maryam Ghalenoei
Volume 4, Issue 2 , September 2017, , Pages 42-49
Abstract
A novel switchable-hydrophilicity solvent based liquid phase microextraction (SHS-LPME) coupled with flame atomic absorption spectrometry has been applied for preconcentration and extraction of Ag(I). In this study, Triethylamine (TEA) was selected as switchable solvent. The Ag (I)-1-(2-pyridylazo)-2-naphthol ...
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A novel switchable-hydrophilicity solvent based liquid phase microextraction (SHS-LPME) coupled with flame atomic absorption spectrometry has been applied for preconcentration and extraction of Ag(I). In this study, Triethylamine (TEA) was selected as switchable solvent. The Ag (I)-1-(2-pyridylazo)-2-naphthol complex was extracted into organic phase by converting the protonated carbonate (P-TEA-C) to TEA. The experimental conditions were optimized using Plackett–Burman and Box–Behnken design methods. Under the optimum conditions, the detection limit, relative standard deviation and the enrichment factor were 0.35 μg L-1, 1.4% and 68, respectively. The calibration graph was linear over the range 2 to 500 μg L-1 with correlation coefficient of 0.997. The proposed method was successfully applied to determine of trace silver in water samples.
Zarrin Es’haghi; Zohreh Rezaeifar
Volume 2, Issue 1 , March 2015, , Pages 43-49
Abstract
This research is on the improvement of the procedure to determination of trace levels of antidepressant drug; fluoxetine in wastewaters. In this research a silica based sol-gel was applied for the extraction of fluoxetine from water samples. This two-phase technique is consisting of aqueous samples of ...
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This research is on the improvement of the procedure to determination of trace levels of antidepressant drug; fluoxetine in wastewaters. In this research a silica based sol-gel was applied for the extraction of fluoxetine from water samples. This two-phase technique is consisting of aqueous samples of fluoxetine (donor phase) and silica based nanocomposite prepared by sol-gel technique (acceptor phase). Accepter phase was held in the pores and lumen of polypropylene hollow fiber segment. Microextraction experiments were carried out in two steps; extraction from analyte samples by sorbent which is held into the hollow fiber segment and desorption of drug from hallow fiber by using of methanol. Desorbed analyte in order to measurement were offered to HPLC and UV-V is spectrophotometer for further analysis. This method is simple, fast and adopted by a majority of the instrumental methods. Extraction parameters such as sol-gel aging time, pH of donor phase, volume of donor phase, extraction time, stirring rate and effect of surfactant were investigated and optimized. The measurements were done under the optimal conditions. This technique has many advantages, such as the short extraction time, low consumption of organic solvents, elimination of carry-over effect, low limit of detection and high pre-concentration factor. The pre-concentration factor and limit of detection have been gained 3227 and 0.53 ng mL-1, respectively. The linear range and relative standard deviation are 1.0-10000.0 ng mL-1 and 4.8% (n=3), respectively.
Shirin Bouroumand; Farzane Marahel; Fereydoon Khazali
Abstract
Fluorescent chemical sensors to detect drugs, by increasing fluorescence emission and absorption or by shutting down, because they are non-destructive, the ability to show decomposed concentrations, fast response, high accuracy have been considered and used. In this research, a chemical sensor was synthesized ...
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Fluorescent chemical sensors to detect drugs, by increasing fluorescence emission and absorption or by shutting down, because they are non-destructive, the ability to show decomposed concentrations, fast response, high accuracy have been considered and used. In this research, a chemical sensor was synthesized PbS functionalized with gelatin quantum dots for (MNZ) drug. The calibration curve was linear in the range of (0.1 to 10.0 µg L−1). The standard deviation of (3.5%), and detection limit of the method (2.2 µg L−1 in time 50 sec, 285 nm) were obtained for sensor level response PbS Quantum Dot–Gelatin Nano composites sensor with (95%) confidence evaluated. The observed outcomes confirmed the suitability recovery and a very low detection limit for measuring the (MNZ) drug. The method fluorometric introduced to measure (MNZ) drug in real samples such as urine and blood was used and can be used for hospital samples. The chemical PbS Quantum Dot–Gelatin Nano composites sensor made it possible as an excellent sensor with good reproducibility.
Mohammad Mazloum-Ardakani; Zahra Alizadeh; Laleh Hosseinzadeh; Bibifatemeh Mirjalili; Naeimeh Salehi
Abstract
In this work, we synthesis and application of functionalized carbon nanotubes (CNTs) In this work, we synthesis and application of functionalized carbon nanotubes (CNTs) with6-amino-4-(3,4-dihydroxyphenyl)-3-methyl-1,4-dihydropyrano[2,3-c]pyrazole-5 carbonitrile (pyrazole derivative (APC)) as sensing ...
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In this work, we synthesis and application of functionalized carbon nanotubes (CNTs) In this work, we synthesis and application of functionalized carbon nanotubes (CNTs) with6-amino-4-(3,4-dihydroxyphenyl)-3-methyl-1,4-dihydropyrano[2,3-c]pyrazole-5 carbonitrile (pyrazole derivative (APC)) as sensing platform toward hydrazine (HZ). Electrochemical properties of functionalized carbon nanotubes composite (APC-CNT) were investigated by cyclic voltammetry, chronoamperometry and differential pulse voltammetry techniques. It was found that the APC-CNT composite exhibited a pair of redox peaks, which is due to the electron transfer between the APC and the glassy carbon electrode. The electrocatalytic properties of the APC-CNT composite for HZ oxidation was remarkably increased as compared to only CNTs. The kinetic parameters of the APC-CNT composite in the presence and absence of HZ was studied by electrochemical methods. The APC-CNT modified electrode revealed an excellent voltammetric response to oxidation of HZ with a wide linear range from 0.01 μM to 120.0 µM and limit of detection of 8.6 nM. Also, APC-CNT modified electrode shows high selectivity, good stability, reproducibility with a RSD less than 2.11%.
Razieh Razavi; Seyyed Mohammad Ali Hossein; Nabi Poodineh Tamiiz
Abstract
In this research study Polypyrrole nanoparticles were synthesized on the copper surface using the amperometry technique, and their morphology, particle size, and thermal properties were investigated. Titanium dioxide particles were added to the texture of polypyrrole nanoparticles as the filler in order ...
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In this research study Polypyrrole nanoparticles were synthesized on the copper surface using the amperometry technique, and their morphology, particle size, and thermal properties were investigated. Titanium dioxide particles were added to the texture of polypyrrole nanoparticles as the filler in order to increase electron transfer in the active layer of the solar cell. Polypyrrole nanoparticles were electrochemically synthesized in the shortest time possible with an ideal morphology and a particle size of less than 40 nm using a new multi-step amperometry technique. The results of EDAX analysis confirmed the existence of titanium particles in the texture of polypyrrole. The crystal size was determined through XRD analysis. SEM images confirmed the uniform and spherical appearance of polypyrrole nanoparticles with spongy and porous structures. Based on the results, the increase in the efficiency of the prepared solar cell based on polypyrrole/TiO2 nanocomposite coated on the copper surface (compared to common polymeric solar cells) was 39.7%. Application of copper as the conductive metal surface improves the electrical conductivity .
Hassan Karami; Fariba Goli
Volume 3, Issue 1 , March 2016, , Pages 55-62
Abstract
Water pollution by heavy metal ions such as Pb occur globally. The conventional methods for the heavy metal ions removal from the water include electrochemical and chemical precipitations, ion exchange, reverse osmosis and sorption. Among the above mentioned different methods, sorption of heavy metal ...
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Water pollution by heavy metal ions such as Pb occur globally. The conventional methods for the heavy metal ions removal from the water include electrochemical and chemical precipitations, ion exchange, reverse osmosis and sorption. Among the above mentioned different methods, sorption of heavy metal ions on the surface of solid nanomaterials is one of the most recommended and interest methods. Sorption is attractive due to its merits of efficiency, cheap and simple operation. In this study, hematite/magnetite/iron nanocomposite (MHINC) is synthesized by the low voltage electrical arc method in the presence of 1.2 Tesla external magnetic fields. Scanning electron microscopy and transmission electron microscopy show that the synthesized MHINC includes uniform nanoparticles with 7 nm average diameters. The prepared MHINC is used as a new sorbent to remove heavy metal ions from polluted waters. Experimental data shows that the sorption of lead ions on the surface of MHINC is acceptably fitted to the Langmuir isotherm. Based on the experimental data, a maximum sorption capacity of 86 mg g-1 is achieved for the sorption of lead ions on the surface of MHINC. The experimental optimum conditions for the lead ion removal includes pH=5, 25 ml sample volume, 25 mg sorbet and 25 min mixing time in the room temperature. Desorption studies showed the adsorbed lead ions on MHINC surface can be done by using 1ml acidic solution containing 3 M HCl and 2 M HNO3.
Sibaprasad Sahoo; Nisarg H. Desai; Anil Bhatt; K. Shivramchandra; B.V. Kamath
Volume 2, Issue 2 , September 2015, , Pages 112-119
Abstract
A rapid, specific and accurate proton quantitative Nuclear Magnetic Resonance spectroscopic (1H qNMR) and also a reversed phase derivatization HPLC method have been developed to quantify a toxic, UV-visible inactive and non-volatile impurity N,N-Dimethylamine hydrochloride (DMA∙HCl) in Metformin Hydrochloride ...
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A rapid, specific and accurate proton quantitative Nuclear Magnetic Resonance spectroscopic (1H qNMR) and also a reversed phase derivatization HPLC method have been developed to quantify a toxic, UV-visible inactive and non-volatile impurity N,N-Dimethylamine hydrochloride (DMA∙HCl) in Metformin Hydrochloride (MF∙HCl), an Active Pharmaceutical Ingradient. The method is based on proton quantitative NMR spectroscopy (1H qNMR) using Glycine as internal standard and deuterium oxide (D2O) as diluent. Both the methods have been validated as per the parameters of ICH guidelines and are found to be comparable.The advantages of the proposed 1H qNMR method are that no certified reference standard of DMA∙HCl is required for quantification, the method is specific, non-destructive and can be applied for quantification of DMA∙HCl in process, quality control for the manufacturing of Metformin hydrochloride as well as commercial dosage form products.
Naser Samadi; Reza Ansari; Bakhtiar Khodavirdilo
Volume 3, Issue 2 , September 2016, , Pages 127-136
Abstract
In this study chelating resins have been considered to be suitable materials for the recovery of Manganese(II) ions in water treatments. These modified resins were further reacted with 1,2-diaminoethan in the presence of ultrasonic irradiation for the preparation of a tridimensional chelating resin ...
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In this study chelating resins have been considered to be suitable materials for the recovery of Manganese(II) ions in water treatments. These modified resins were further reacted with 1,2-diaminoethan in the presence of ultrasonic irradiation for the preparation of a tridimensional chelating resin on the Nano scale for the recovery of Manganese II) ions from aqueous solutions. In this work we used copolymers derivate resin of poly (styrene – Alternative - Maleic Anhydride) and Atomic Absorption Spectroscopy for removing and determining Manganese(II) ions .The method is simple, sensitive, inexpensive and fast. The adsorption behavior of Manganese(II) ions were investigated by the synthesis of chelating resins at various pH’s. The prepared resins showed a good tendency for removing the selected metal ions from aqueous solution, even at acidic pH. Also, the prepared resins were examined for the removal of Manganese(II) ions from real samples such as industrial wastewater and were shown to be very efficient at adsorption in the cases of Manganese(II) ions . The pseudo-first-order, pseudo-second-order and intra-particle diffusion kinetics equations were used for modeling of adsorption data and it was shown that pseudo-second-order kinetic equation could best describe the adsorption kinetics. The intra-particle diffusion study revealed that external diffusion might be involved in this case. The resins were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction analysis.
Kumble Divya; Badiadka Narayana
Volume 1, Issue 1 , March 2014, , Pages 29-35
Abstract
New, simple and cost effective spectrophotometric methods have been developed for the quality assessment of isoniazid (INH), in bulk and in pharmaceutical formulations by using novel reagents. The proposed methods involve the utility of ethyl 2-[(E)-(4-hydroxyphenyl) diazenyl]-3-oxobutanoate and benzil ...
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New, simple and cost effective spectrophotometric methods have been developed for the quality assessment of isoniazid (INH), in bulk and in pharmaceutical formulations by using novel reagents. The proposed methods involve the utility of ethyl 2-[(E)-(4-hydroxyphenyl) diazenyl]-3-oxobutanoate and benzil as novel reagents for the determination of INH. Developed methods are based on the condensation reaction of INH with reagents to give orange colored chromogen with an absorption band at 454 nm (for method A) and 436 nm (for method B). The applicability of these methods is demonstrated by the determination of the studied drug in commercial tablets and the results are statistically evaluated. The new procedures described in this paper are fast, convenient and have the novelty of carrying out the quantitative determination of INH in pure and in pharmaceutical formulation.
Azar Bagheri Gh.
Volume 2, Issue 1 , March 2015, , Pages 50-56
Abstract
Spectrophotometric and electrochemical studies were successfully used in quantitative analysis of Amitriptyline Hydrochloride (ATH) and Nortriptyline Hydrochloride (NTH). Conductometric titration were carried out in equeous solution using iodide and dopamine and serotonine as titrant. Two new methods ...
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Spectrophotometric and electrochemical studies were successfully used in quantitative analysis of Amitriptyline Hydrochloride (ATH) and Nortriptyline Hydrochloride (NTH). Conductometric titration were carried out in equeous solution using iodide and dopamine and serotonine as titrant. Two new methods using spectrophotometry are dascribed for the determination of (ATH) and (NTH) with potassium bromate as the oxidizing agent and acid dyes, Methyl orange and Indigo carmine. Both spectrophotometric methods are based on the oxidation of mentioned drugs by a known excess of bromate in acid medium and in the presence of excess of bromide followed by estimation of surplus oxidant by reacting with either Indigo carmine (method A) or Methyl orange (method B) and measuring the absorbance at 609 or 507 nm.
Reza Ansari; Naser Samadi; Bakhtiar Khodavirdilo
Volume 4, Issue 2 , September 2017, , Pages 50-60
Abstract
In this research poly (Styrene–Alternative-Maleic Anhydride) (SMA) and derivations of SMA with Melamine, (Melamine + 1,2 Diamino Ethane) and (Melamine + 1,3 Diamino Propane) CSMA-M, CSMA-ME and CSMA-MP were synthesized, respectively. This method is very simple, cheap, precise and used ...
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In this research poly (Styrene–Alternative-Maleic Anhydride) (SMA) and derivations of SMA with Melamine, (Melamine + 1,2 Diamino Ethane) and (Melamine + 1,3 Diamino Propane) CSMA-M, CSMA-ME and CSMA-MP were synthesized, respectively. This method is very simple, cheap, precise and used polymers recyclable to seven terms. The purpose of the present work was exploring the adsorption power of CSMA-M and its derived polymer to removed silver(I) ions from aqueous solution. In this research, batch adsorption tests were exhibited and the effect of different parameters on this removal process has been studied. The effects of pH, adsorption time, metal ion concentration and the acidic remedy on the adsorption process were optimized. The optimum pH for adsorption was found to be 6.0. In adsorption explores, remained Ag+ concentration arrives equilibrium in a short duration of 60 min. Maximum adsorption capacity, 67.57, 76.90 and 95.24 mg Ag+/g polymer CSMA-M, SMA–ME and SMA–MP respectively.showed that this adsorbents were appropriate for removing silver(I) from aqueous solution. The resins were characterized by Fourier transform Infra Red(FT-IR) spectroscopy, Scanning Electron Microscopy (SEM), X-ray diffraction(XRD) and Differential Scanning Calorimetry (DSC), (Thermo Gravimetric Analysis) TGA analysis.
Arefeh Gorgij; Hamid Ahmar; Laleh Adlnasab
Abstract
This research aimed to develop a novel sensing platform for hydrogen peroxide (H2O2) quantification in the milk samples. The proposed sensor was fabricated using a glassy carbon electrode modified with Fe-Cu layered double hydroxide (LDH)/magnetic Fe3O4 nanoparticles (FeCu-LDH@Fe3O4/GCE). The resulting ...
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This research aimed to develop a novel sensing platform for hydrogen peroxide (H2O2) quantification in the milk samples. The proposed sensor was fabricated using a glassy carbon electrode modified with Fe-Cu layered double hydroxide (LDH)/magnetic Fe3O4 nanoparticles (FeCu-LDH@Fe3O4/GCE). The resulting sensor was characterized using field emission scanning, electron microscopy, x-ray diffraction, and infrared spectroscopy, with the addition of the electrochemical methods. After optimization of affecting parameters, the FeCu-LDH@Fe3O4/GCE exhibited a high electrocatalytic activity for H2O2 electroreduction; and high cathodic peak currents were obtained. The proposed electrode also illustrated a wide linear dynamic domain in the range of 2 to 400 µM; and low limit of detection was calculated to be 0.6 µM.
Karim Asadpour-Zeynali; Yaser Arteshi
Volume 4, Issue 1 , March 2017, , Pages 51-58
Abstract
In this research, an inexpensive and effective method for determination of Isoniazid (INH) is presented by using a poly (Eriochrome black T) modified pencil lead electrode. The potential of modified electrode in electrochemical sensing of INH was evaluated by cyclic voltammetry and hydrodynamic amperometry ...
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In this research, an inexpensive and effective method for determination of Isoniazid (INH) is presented by using a poly (Eriochrome black T) modified pencil lead electrode. The potential of modified electrode in electrochemical sensing of INH was evaluated by cyclic voltammetry and hydrodynamic amperometry methods. The overall number of electrons involved in oxidation of INH was fond 4 electrons. The calculate diffusion coefficient for INH was equal to 9.74 × 10-7 cm2/s. Calculated limit of detection for method was 66.0µM and 20.4µM applying cyclic voltammetry and hydrodynamic amperometry methods, subsequently. The ability of prepared electrode for determination of INH in real sample was evaluated by applying the proposed method to human plasma analysis and the results were compared with the standard method, presented by United State Pharmacopeia. Presented method exhibited a satisfying precision (%RSD=4.64). Also the proposed method showed a good accordance with standard method in confidence level of 95%.
Foroozan Hasanpour; Mina Teimouri; Akram Eghbali
Volume 5, Issue 2 , September 2018, , Pages 56-61
Abstract
Essential oil of bentazon- treated plants were extracted and herbicide content analyzed by electrochemical method. For this propose, carbon paste electrode was modified using ZnFe2O4 anchored on reduced graphene oxide which synthesized by solvothermal approach. The nature and morphology of nanoparticles ...
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Essential oil of bentazon- treated plants were extracted and herbicide content analyzed by electrochemical method. For this propose, carbon paste electrode was modified using ZnFe2O4 anchored on reduced graphene oxide which synthesized by solvothermal approach. The nature and morphology of nanoparticles were characterized using XRD, FT-IR and Fe- SEM image. Under optimal experimental condition, modified electrode produces powerful oxidation signal for bentazon at +0.95 V (vs. Ag/AgCl). The anodic current was increased linearly with bentazon concentration in the range of 0.1 -20.0 µmol L-1 with a detection limit of 0.07 µmol L-1. The practical usage of modified electrode was evaluated by electro analysis of extracted bentzon residues at three applied doses which revealed reasonable results.
Sayed Zia Mohammadi; Somayeh Tajik; Hadi Beitollahi; Zohreh Barani
Abstract
In the present study, the cysteamine electrochemical features were explored by La2O3/Co3O4 nanocomposite-modified screen printed electrode (La2O3/Co3O4/SPE) using voltammetry, chronoamperometry, and differential pulse voltammetry (DPV) techniques. The synthesized La2O3/Co3O4 nanocomposite qualities were ...
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In the present study, the cysteamine electrochemical features were explored by La2O3/Co3O4 nanocomposite-modified screen printed electrode (La2O3/Co3O4/SPE) using voltammetry, chronoamperometry, and differential pulse voltammetry (DPV) techniques. The synthesized La2O3/Co3O4 nanocomposite qualities were considered by SEM, FT-IR, and XRD analyses. Exploiting the modified SPE electrode with La2O3/Co3O4 nanocomposite, the cysteamine electrooxidation kinetics was significantly enhanced by reducing the anodic over-potential. The constructed La2O3/Co3O4/SPE revealed voltammetric reactions of high sensitivity for cysteamine, resulting in a highly appropriate means of trace levels cysteamine measurement. The electrooxidation peak currents for cysteamine were found to change linearly in relation to its concentrations (1.0–700.0 μM) in detection limit of 0.3 μM. La2O3/Co3O4/SPE was utilized for the cysteamine quantification in real specimens.
Fatemeh Sabermahani; Fariba Honarmand
Abstract
In this study, Magnetic Fe3O4-walnut sawdust nanocompositewas synthesized and used for removal of lead from aqueous solution. The size, structural, optical and morphological properties of nanoparticles have been analyzed by Scanning Electron Microscope )SEM) and Dynamic Light Scattering method. The effect ...
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In this study, Magnetic Fe3O4-walnut sawdust nanocompositewas synthesized and used for removal of lead from aqueous solution. The size, structural, optical and morphological properties of nanoparticles have been analyzed by Scanning Electron Microscope )SEM) and Dynamic Light Scattering method. The effect of pH, contact time, adsorbent dose, initial concentration, ionic strength and the effect of temperature on the adsorption was checked out in a batch process mode. Using the equilibrium constants obtained at different temperatures, the thermodynamic results parameters were calculated as ∆G, ∆H and ∆S. The thermodynamic parameters showed that the uptake of lead is spontaneous and endothermic. The data were fitted with the Langmuir and Freundlich equations to describe the adsorption equilibrium. The maximum adsorption capacity by using Langmuir equation was calculated 12.99 mg/g. The kinetic data followed by Pseudo second. Owing to such outstanding features, Magnetic Fe3O4-walnut sawdust nanocompositeproved the great potential in adsorption lead removal from aqueous solutions.
Mohammad Vahidifar; Zarrin Eshaghi; Ramin Rezaee
Abstract
In this paper, a new rapid and sensitive method based on sodium dodecyl sulfate modified Fe3O4@α–Linolenic acid nanocomposite combined with high-performance liquid chromatography-photo diode array detection (HPLC–PDA) has been proposed for the extraction and determination of tramadol ...
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In this paper, a new rapid and sensitive method based on sodium dodecyl sulfate modified Fe3O4@α–Linolenic acid nanocomposite combined with high-performance liquid chromatography-photo diode array detection (HPLC–PDA) has been proposed for the extraction and determination of tramadol (TRA) in water samples. The Fe3O4@α–Linolenic acid NPs were synthesized and then characterized by Fourier transform-infrared spectroscopy (FT−IR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The main factors influencing extraction and desorption efficiency were optimized. Under optimum conditions, the method was successfully applied to the determination of TRA in the environmental samples and good linearity in the range of 0.1–500ng.mL-1(𝑅2> 0.99) obtained. The detection limit (LOD) and relative standard deviation (RSD) were0.074ng.mL-1 and 2.89 %( n=5) respectively. Finally, the proposed method was successfully applied with the relative recoveries percentages from 94–103.97% for the extraction and determination of tramadol in aqueous samples.
Alireza Mohadesi
Volume 3, Issue 1 , March 2016, , Pages 63-69
Abstract
A differential pulse anodic stripping voltammetric method was developed for the determination of Ag(I) at a carbon paste electrode modified with 4,6-diaminopyrimidine-2-thiol and multi-walled carbon nanotubes. The analysis procedure consisted of an open circuit accumulation step in stirred sample solution ...
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A differential pulse anodic stripping voltammetric method was developed for the determination of Ag(I) at a carbon paste electrode modified with 4,6-diaminopyrimidine-2-thiol and multi-walled carbon nanotubes. The analysis procedure consisted of an open circuit accumulation step in stirred sample solution for 9 min. This was followed by medium exchange to a clean solution where the accumulated Ag(I) was reduced for 15 s in −0.6V. Subsequently an anodic potential scan was affected from −0.2 to +0.3V to obtain the voltammetric peak. The detection limit of silver(I) was 0.08 µgL−1 and R.S.D. for 10 and 100 µgL−1 Ag(I) were 2.4 and 1.2%, respectively. The calibration curve was linear for 0.99–118.57 µgL−1 Ag(I). The procedure was applied to determination of Ag(I) in standard alloys and water samples.
Khanage Shantaram Gajanan; Dharam Prachi Gangadhar; Mohite Popat Baban; Deshmukh Vinayak Kashinath
Volume 2, Issue 2 , September 2015, , Pages 120-126
Abstract
A simple, sensitive, accurate and precise simultaneous UV spectrophotometric method has been developed for the estimation of Carisoprodol, Paracetamol and Caffeine in tablet dosage form. The absorption maxima of the drugs were found to be 221, 248 and 273 nm for Carisoprodol, Paracetamol and Caffeine ...
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A simple, sensitive, accurate and precise simultaneous UV spectrophotometric method has been developed for the estimation of Carisoprodol, Paracetamol and Caffeine in tablet dosage form. The absorption maxima of the drugs were found to be 221, 248 and 273 nm for Carisoprodol, Paracetamol and Caffeine respectively, in methanol, using a double beam UV/Visible Spectrophotometer. Carisoprodol, Paracetamol and Caffeine obeyed Beer’s law in the concentration range of 0.4-2 μg/mL, 2-10 μg/mL and 2-10 μg/mL, respectively. The correlation coefficient was found to be 0.9922, 0.9917 and 0.9943 for Carisoprodol, Paracetamol and Caffeine, respectively. The method was validated for various parameters according to International Conference on Harmonization guidelines. The low relative standard deviation values indicate a good precision and high recovery values indicate the accuracy of the proposed method.
