Azar Sa'adi; Javad Shabani-Shayeh; Zarrin Eshaghi
Abstract
The electro-oxidation of acyclovir (ACV) was studied using synthesized Cu nanoparticles stabilized by reduced graphene oxide (Cu/RGO) modified carbon paste electrodes. In this work, leaf extract of rosemary (Rosmarinus officinalis) used as a reducing and stabilizing agent for biosynthesis of copper nanoparticles. ...
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The electro-oxidation of acyclovir (ACV) was studied using synthesized Cu nanoparticles stabilized by reduced graphene oxide (Cu/RGO) modified carbon paste electrodes. In this work, leaf extract of rosemary (Rosmarinus officinalis) used as a reducing and stabilizing agent for biosynthesis of copper nanoparticles. The Cu/RGO nanocomposite was authorized by X-ray diffraction (XRD), Fourier transformed infrared (FT-IR) spectroscopy, [1]Scanning electron microscopy (SEM), and Transmission electron microscopy (TEM). In an alkaline solution, the electrochemical performance of Cu/RGO was checked and afterward utilized to make a modified carbon paste electrode to study the electrocatalytic oxidation of acyclovir, compared to copper modifier only. Two used methods for surveying of the oxidation reaction were cyclic voltammetry and chronoamperometry. The limit of detection for modified electrode was obtained 0.63 µM. Furthermore, the rate constant of the electrocatalytic oxidation of acyclovir was (1.80 ± 0.03) ×105 cm3mol−1s−1 and the electron-transfer coefficient was (4.00 ± 0.05) ×10–6 Cm2 s–1.
Sayyed Hossein Hashemi; Massoud Kaykhaii; Ahmad Jamali Keikha; Enayat Saberi
Abstract
This paper describes trace determination of malachite green (MG) as a water pollutant dye by convenient spectrophotometry. A water-soluble hyper-branched polyamine was first prepared using the nuclophilic ring opening reaction of diepoxy and diamine monomer, which was then used for functionalization ...
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This paper describes trace determination of malachite green (MG) as a water pollutant dye by convenient spectrophotometry. A water-soluble hyper-branched polyamine was first prepared using the nuclophilic ring opening reaction of diepoxy and diamine monomer, which was then used for functionalization of multiwalled carbon nanotubes. This compound (named WHPA-OMCNT) was applied as a highly efficient adsorbent for the extraction of MG from seawater samples of Chabahar Bay (located in the southern east of Iran). WHPA-OMCNT was used in a pipette-tip solid phase extraction process; and for this extraction, different parameters affecting the extraction efficiency, including type and volume of eluent solvent, sample of volume, number of cycles of extraction and elution, pH of sample solution, type and amount of salt, and concentration of surfactant (triton X-114) were optimized using both one-variable-at-a-time and Box-Behnken response surface methodology techniques employing seven factors in three-levels. Under optimum conditions, the linear range of proposed method for MG was 4-250 µg L-1 with a detection limit of 0.80 µg L-1 and RSDs better than 6.4%.
Matina Azad Roosta; Atefeh Tamaddon; Elham Moniri
Abstract
In present work Hengam island sands were used for preparation of new magnetic nano-adsorbent. These sands have intrinsic magnetic properties due to possess specific compounds such as Fe3O4. It was modified by surface activator agent namely 3-(Glycidyloxypropyl)trimethoxysilane to produce effective nano-adsorbent. ...
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In present work Hengam island sands were used for preparation of new magnetic nano-adsorbent. These sands have intrinsic magnetic properties due to possess specific compounds such as Fe3O4. It was modified by surface activator agent namely 3-(Glycidyloxypropyl)trimethoxysilane to produce effective nano-adsorbent. After preparation of this nano-adsorbent, Its physical and chemical properties was verified using several techniques such as FTIR, TGA/DTG, XRD and SEM. Nano-adsorbent was used as a solid phase to extraction of cetirizine from aqueous solutions and then its determination was done by HPLC. Effective analytical parameters such as pH of sample solution (pH=4), dosage of nano-adsorbent (100 mg), zero charge (pHz=5), breakthrough volume (500 mL) and contact time (15 min) were evaluated and optimized. Furthermore, figures of merit parameters such as precision (RSD=1.44%), limit of detection (LOD=1.1 µg L-1) and linear dynamic range (LDR=0.01-250 mg L-1) were obtained. Also for validation the accuracy of method, amount of cetirizine in two real samples were successfully determined.
Fatemeh Banifatemeh
Abstract
Effect of fibers of seeds inside Cucumis melon (Persian melon) extract (FE) and Cucumis melon leaves extract (LE) were investigated as descaler and inhibitor. In one part of this research, the effect of LE and FE for the solvent of Ca precipitates was investigated by gravimetric and electrochemical measurements. ...
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Effect of fibers of seeds inside Cucumis melon (Persian melon) extract (FE) and Cucumis melon leaves extract (LE) were investigated as descaler and inhibitor. In one part of this research, the effect of LE and FE for the solvent of Ca precipitates was investigated by gravimetric and electrochemical measurements. The decrease in the weight of calcium precipitate in the solution containing the extracts shows that the FE has the best effect as a solvent of Ca precipitate with 62% efficiency due to lower pH. A comparison of the hardness of the solutions after dissolving the calcium precipitate shows an increase of about 3 times the hardness of the solution containing FE compared to the blank. The second part is dedicated to the study of corrosion inhibition behavior of extracts on Cu corrosion in brine and acid solution by Tafel plot and electrochemical impedance spectroscopy (EIS). The solution containing the LE and FE shows higher polarization resistance (Rp) (about 3.5 times) and lower corrosion current density than the blank solution. While the LE shows more positive potential than the FE. Based on the results,the FE can be used to formulate a low-cost and environmentally friendly descaling agent, and the LE can be used as a green corrosion inhibitor.
Arash Mohammadinejad; Mahmoud Ebrahimi; Ali Morsali; Zarrin Es’haghi; Hamed Chegini; Abdolhossein Ebrahimitalab
Volume 3, Issue 1 , March 2016, , Pages 27-37
Abstract
In this work, a carbon paste electrode modified with multiwall carbon nanotubes (MWCNTPE) was used for the sensitive voltammetric determination of acetaminophen (AC) in biological and pharmaceutical samples. The electrochemical behavior of acetaminophen was investigated employing cyclic voltammetry. ...
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In this work, a carbon paste electrode modified with multiwall carbon nanotubes (MWCNTPE) was used for the sensitive voltammetric determination of acetaminophen (AC) in biological and pharmaceutical samples. The electrochemical behavior of acetaminophen was investigated employing cyclic voltammetry. It was revealed that the standard electrode potential of half reaction for AC(O), H+/AC(R) was 0.898 V. under the optimized experimental conditions, the oxidation peak current for acetaminophen was found to vary linearly with concentration range of 0.12 to 99 µM with detection limit of 0.06 µM using differential pulse voltammetry. DFT-B3LYP/6-31G (d,p) and HF/6-31G (d,p) calculations were performed for deoxidized acetaminophen (AC(R)) and its oxidized form (AC(O)). The calculated standard electrode potentials are relatively in agreement with experimental data. This electrode was employed for determination of acetaminophen in hospital waste water, hair, blood and pharmaceutical samples considering its high sensitivity, low detection limit, good reproducibility and its non-existent interference at trace levels in clinical and quality control laboratories.
Nosrat Madadi Mahani; Fatemeh Sabermahani; Peyman Mohammadzadeh Jahani; Nahid Jalali
Volume 2, Issue 2 , September 2015, , Pages 70-76
Abstract
The Quantitative Structure–Activity Relationship of a series of novel Thiazoline derivatives with anticancer activity has been studied by using the density functional theory by B3LYP/ 6-31G. Descriptors of quantum mechanics of 21 thiazoline derivatives with known activity were obtained. Multiple ...
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The Quantitative Structure–Activity Relationship of a series of novel Thiazoline derivatives with anticancer activity has been studied by using the density functional theory by B3LYP/ 6-31G. Descriptors of quantum mechanics of 21 thiazoline derivatives with known activity were obtained. Multiple linear regressions were employed to model the relationships between molecular descriptors and biological activity of molecules using stepwise method. The most model shows not only significant statistical quality, but also predictive ability, with the square of adjusted correlation coefficient (R2=0.945) and standard error (SE=0.586). We find that the anticancer activity expressed that as half maximal inhibitory concentration (IC50), closely relates to the highest occupied molecular orbital, dipole moment, softness, hardness, ionization energy, electron affinity. Accordingly can be offered a quantitative model, and interpret the activity of the compounds relying on the multivariate statistical analysis. This study shows that the prediction results were in excellent agreement with the experimental value. The results can offer some useful references for understanding the action mechanism and designing new compounds with anticancer activity.
Ali Yeganeh-Faal; Ghazal Parvan
Volume 3, Issue 2 , September 2016, , Pages 88-95
Abstract
In this work, the first, intense and efficient POCL arising from the reaction of bis (2, 4, 6-trichlrophenyl) oxalate (TCPO) with hydrogen peroxide in the presence of N-[4-(dimethyl amino) benzylidene] benzoxide (Nitrone) as a new luminophor has been reported. The relationships between the chemiluminescence ...
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In this work, the first, intense and efficient POCL arising from the reaction of bis (2, 4, 6-trichlrophenyl) oxalate (TCPO) with hydrogen peroxide in the presence of N-[4-(dimethyl amino) benzylidene] benzoxide (Nitrone) as a new luminophor has been reported. The relationships between the chemiluminescence intensity and concentrations of all reagents were investigated. The quenching effect of some cations and compounds such as Fe3+, Co2+, Cu2+, Mn2+, Ni2+, Cd2+ ions and imidazole, L-Histidine, L-Tyrosine, D-(+)-Lactose, and D-(+)-Sucrose, on the POCL system were investigated. The KQ values were calculated from Stern–Volmer equation. It was found that the KQ values decreases in the order: Co2+ > Fe3+ > Cu2+ > Mn2+ > Ni2+ > Cd2+ and D-(+)-Lactose > Imidazole > L-Tyrosine > L-Histidine > D-(+)-Sucrose. Dynamic range and detection limit of all quencher were determined. Sucrose has the best dynamic range and low detection limit, so sucrose considered as an analyte and then the total sucrose extracted from sugar beet as real sample was measured by this proposed method. Dynamic range, detection limit, mean intra-day and inter-day relative standard deviation (RSD%) were 6.67×10-7- 1.20×10-5, 1.0×10-8, 5.62%, 7.25% (n=3) respectively. For accuracy determination, the percentage recovery was found 97.4%- 104.3%. All interferences were investigated and Co2+, D-(+)-Lactose had most interference. Sucrose percentage of the measured sample was 17 percent. These results are comparable with the results of the standard method to determine the sucrose and is acceptable.
Shivani A. Trivedi; Dharati M. Joshi; Samir G. Patel; Rajendra K. Patel; Archita J. Patel
Volume 2, Issue 1 , March 2015, , Pages 14-21
Abstract
The present study was aimed to develop and validate a high performace liquid chromatography method for determination of thiocolchicoside and dexketoprofen trometamol in combined dosage form. The proposed HPLC method utilizes an Agilent Eclipse C-8 column (5 µm, 250×4.6 mm) at ambient temperature. ...
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The present study was aimed to develop and validate a high performace liquid chromatography method for determination of thiocolchicoside and dexketoprofen trometamol in combined dosage form. The proposed HPLC method utilizes an Agilent Eclipse C-8 column (5 µm, 250×4.6 mm) at ambient temperature. A 23 full factorial design was performed for optimization of mobile phase for separation of two drugs. For the factorial design, the dependent variables chosen were % of acetonitrile, % of 0.1% o-phosphoric acid and pH. The optimum mobile phase consisted of acetonitrile: 0.1% o-phosphoric acid in water (41.9:58.1; pH 2.6). The flow rate was kept 1 mL/min with UV detection at 254 nm. The run time was found to be 1.41 min and 7.58 min for thiocolchicoside and dexketoprofen trometamol, respectively. The method was validated as per ICH guidelines. The calibration plots were linear in the range of 1-5 μg/mL with r2=0.998 for thiocolchicoside and 6-30 μg/mL with r2 = 0.995 for dexketoprofen trometamol. The % recovery values were found to be 98.52 ± 1.21 and 98.16 ± 1.45 for thiocolchicoside and dexketoprofen trometamol, respectively. The minimum detectable and minimum quantifiable amounts were found to be 0.11 and 0.35 μg/mL, respectively for thiocolchicoside and 1.41 and 4.38 μg/mL, respectively for dexketoprofen trometamol. The developed method could be utilized successfully in simultaneously analyzing the drugs in bulk as well as combined dosage form.
Mohammad Mazloum-Ardakani; Fatemeh Jokar; Hamideh Mohammadian-Sarcheshmeh; Bi Bi Fatemeh Mirjalili; Sahar Saadat Hosseinikhah
Abstract
Recently, different significant efforts have been made to fabricate an effectively modified electrode for replying to the growing requests for enhanced performance electrodes for electrochemical sensors. Herein, we introduced an organic material along with a composite of the zinc sulfide (ZnS) particles ...
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Recently, different significant efforts have been made to fabricate an effectively modified electrode for replying to the growing requests for enhanced performance electrodes for electrochemical sensors. Herein, we introduced an organic material along with a composite of the zinc sulfide (ZnS) particles distributed in the substrate of carbon nanotubes (CNTs)/reduced graphene oxide (RGO) nanosheets by using an inexpensive, simple, and one-step fabrication method, as an effectively modified electrode for the determination of hydrazine as an analyte. This electrode represents a great electrochemical performance with a large linear range (0.01 μM-60.0 μM) and a proper limit of detection value (0.006 µM) for determination of hydrazine. Good recovery percentage values for the proposed sensor confirm its excellent ability to measure hydrazine.
Peyman khanaliluo; Azar Bagheri Gh.; Tayebeh Mosanegad
Volume 4, Issue 2 , September 2017, , Pages 17-21
Abstract
The catalytic degradation of 4-chloro 2-nitro phenol aromatic compound has been studied with coupled ozone-sonolysis method. The response surface methodology was used to optimize the influence of operation parameters on the catalytic degradation of 4-chloro 2-nitro phenol. In order to evaluate the influence ...
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The catalytic degradation of 4-chloro 2-nitro phenol aromatic compound has been studied with coupled ozone-sonolysis method. The response surface methodology was used to optimize the influence of operation parameters on the catalytic degradation of 4-chloro 2-nitro phenol. In order to evaluate the influence of operation conditions in the degradation of 4-Chloro 2-Nitro Phenol, four independent variable chosen: 4-Chloro 2-Nitro Phenol concentration, mass flow rate of O3, TiO2 concentration and ultra sonic power. Analysis of variance was employed to consider main factors effects and interactive effects in the optimization of catalytic degradation of of 4-Chloro 2-Nitro Phenol. Analysis of variance results present that the model is statistically significant. The response surface methodology predictions were in agreement with the experimental values.
Hadi Farahani; Mehdi Rahimi-Nasrabadi
Volume 5, Issue 1 , March 2018, , Pages 17-24
Abstract
An efficient carbon dot-dispersive liquid-liquid microextraction followed by UV-Vis spectrophotometry (CD-DLLME-UV-Vis) has been effectively developed for the sensitive determination of 1,3,6,8-tetranitrocarbazole (TNC) in environmental water samples. In this DLLME-based method, home-made syntheses ...
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An efficient carbon dot-dispersive liquid-liquid microextraction followed by UV-Vis spectrophotometry (CD-DLLME-UV-Vis) has been effectively developed for the sensitive determination of 1,3,6,8-tetranitrocarbazole (TNC) in environmental water samples. In this DLLME-based method, home-made syntheses carbon dots (CDs) were directly extracted into carbon tetrachloride using trioctylmethylammonium chloride (aliquat 336), which works as a disperser agent. By applying inherent colorimetric feature, the enriched CDs exhibited an intensive absorption signal at 300 nm, which swelled up in the presence of TNC due to their interaction at the colloidal interface. Main parameters that controlling and affecting the performance of the microextraction process were evaluated and optimized in details. An enrichment factor of 55.5 beside a meaningful sample clean-up was achieved under the optimized conditions. The calibration curve was linear in the range of 1-200 ng mL-1 with regression coefficient corresponding to 0.999. Limit of detection (S/N = 3) was 0.2 ng mL-1 while the RSD% values (n = 10) for the target analyte at two concentration levels of 20 and 100 ng mL-1 were 3.6 and 1.7, respectively. The proposed method was ultimately exerted for the preconcentration and determination of TNC in various environmental water samples and admissible results were achieved.
Mohammad Mazloum-Ardakani; Mehrorang Ghaedi; Shaaker Hajati; Behnaz Barazesh
Volume 5, Issue 2 , September 2018, , Pages 17-22
Abstract
Two locally available, cost-effective, renewable biosorbents including the untreated straw of Smyrniopsis Aucheri and untreated leaf of Acer Negundo were used for the removal of Methylene Blue dye. The influence of initial dye concentration on the dye removal was investigated. Isotherm and kinetics ...
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Two locally available, cost-effective, renewable biosorbents including the untreated straw of Smyrniopsis Aucheri and untreated leaf of Acer Negundo were used for the removal of Methylene Blue dye. The influence of initial dye concentration on the dye removal was investigated. Isotherm and kinetics of the biosorption process were studied. The optimum pH was found to be 6 and 5 for Smyrniopsis Aucheri and Acer Negundo, respectively. The optimum biosorbent dosage was found to be 0.3 g for Smyrniopsis Aucheri and 0.5 g for Acer Negundo. The removal of Methylene Blue by Smyrniopsis Aucheri and Acer Negundo occurred during 10 and 15 min, respectively. The quick biosorption using reasonably small amount of such natural and untreated materials is a big advantages of this work for wastewater treatment applications in an environmental friendly way. The Langmuir adsorption isotherm model, was found to be the best applicable one to fit the experimental data. The pseudo-second and pseudo-first order kinetic models were applied well to describe the kinetics of Smyrniopsis Aucheri and Acer Negundo biosorption, respectively.
Naser Samadi; Mahzad Golafshan Yeganeh
Volume 4, Issue 1 , March 2017, , Pages 18-24
Abstract
In this study, an oral insulin delivery system, based on Biocompatible and smart pH sensitive Hydrogel (PSH) on to natural polymer nano-cellulose backbones has been designed. PSH is made of mixed acrylic acid and 2-hydroxyethyl methacrylate on the nano-cellulose backbones and has been identified by using ...
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In this study, an oral insulin delivery system, based on Biocompatible and smart pH sensitive Hydrogel (PSH) on to natural polymer nano-cellulose backbones has been designed. PSH is made of mixed acrylic acid and 2-hydroxyethyl methacrylate on the nano-cellulose backbones and has been identified by using FT-IR and SEM methods. Synthetic networks, can sense the pH environment changes and lead to the creation of a swinging distribution pattern. The results show that the main factor influencing the behavior of the hydrogels in drug distribution, is the pH environment, so that the rate of drug release from the hydrogel, within 48 hours in a simulated body environment in SIF with pH= 9 and blood plasma-neutral environment with pH= 7.4, (93%) has been in greater amount of it’s release in acidic conditions (SGF with pH= 1.5) and the results have been satisfactory for the preparation of oral insulin.
Adams Udoji Itodo; Rufus Sha’Ato; Johnson Idoko Adaji
Abstract
The study involves the adsorption of potentially toxic metals from brewery effluent (Beff), using size modified (UAD) and chemically modified (TAD) Borassus aethiopum biomass. Preliminary study and characterization of both brewery effluent and the derived adsorbents were recorded, with result ...
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The study involves the adsorption of potentially toxic metals from brewery effluent (Beff), using size modified (UAD) and chemically modified (TAD) Borassus aethiopum biomass. Preliminary study and characterization of both brewery effluent and the derived adsorbents were recorded, with result showing some water quality parameters greater than threshold limits set by legislation. Both classical and instrumental techniques adopted for Sorbent characterization show valid outcome. Batch kinetic studies were monitored along with the role of varying conditions (Effluent concentration, pH, time and temperature) that could influence cadmium (Cd) and chromium (Cr) adsorption. Model applicability test supported the Pseudo second-order, with a high correlation coefficient, least error sum and high precision in qe. cal./exp. The mode of transport is best explained with intra-particle diffusion, not as the only rate limiting process. Generally, the chemically treated biomass exhibited metal removal efficiencies that could compete with the function of commercial activated carbon (CAC).
Sayyed Hossein Hashemi; Fateme Keykha
Abstract
In this research a graphene oxide/zinc oxide nanocomposite (GO/ZnO) was synthesized and employed for simple and sensitive pipette tip-based micro-solid phase extraction (PT-µSPE) of nalidixic acid (NA) from seawater and human blood plasma samples following by its determination by spectrophotometry. ...
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In this research a graphene oxide/zinc oxide nanocomposite (GO/ZnO) was synthesized and employed for simple and sensitive pipette tip-based micro-solid phase extraction (PT-µSPE) of nalidixic acid (NA) from seawater and human blood plasma samples following by its determination by spectrophotometry. Several parameters affecting the suggested protocol were optimized, namely type and volume of eluent, amount of sorbent, sample volume, number of cycles of extraction and elution, pH of sample solution and type and amount of salt. The optimization performed by both response surface methodology (RSM) and one-variable-at-a-time techniques. Figures of merit were achieved as: detection limit; 0.30 µg L-1, enrichment factor 40 for NA, linear calibration curve in the range of 1.0-200.0 µg L-1; and reproducibility (as RSD %) better than 4.4%. Results for the application of the technique in seawater and human blood plasma showed that this analysis method can be applied for the determination of the analyte in complex real samples successfully.
Elahe Salari; massoud Nejati-Yazdinejad; Hamid Ahmar; Laleh Adlnasab
Abstract
Herein, a simple, rapid, and efficient method based on pH assisted homogenous liquid-liquid microextraction was combined with gas chromatography- mass spectrometry (GC-MS) to do trace analysis of polychlorinated biphenyls (PCBs) in water samples. Triethylamine (TEA) was used as a switchable hydrophilicity ...
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Herein, a simple, rapid, and efficient method based on pH assisted homogenous liquid-liquid microextraction was combined with gas chromatography- mass spectrometry (GC-MS) to do trace analysis of polychlorinated biphenyls (PCBs) in water samples. Triethylamine (TEA) was used as a switchable hydrophilicity solvent which can be miscible/immiscible with aqueous sample by varying the pH of the sample solution. In this regard, the effects of various parameters were explored on the extraction performance of PCBs. Detection limits, quantification limits and linear dynamic ranges were equal to 0.15 µg L-1, 0.5 µg L-1 and 0.5-150 µg L-1 respectively. The RSDs% (n = 3) were in the range of 5.2-6.4 and 5.6-7.2 for intra-day and inter-day assays, respectively. Ultimately, the method was employed for determination of PCBs in water samples.
Ahmadreza Amraei; Mohammad Hosseini; Rouhollah Heydari; Ali Niazi
Abstract
Simultaneous spectrophotometric determination of some polycyclic aromatic hydrocarbons (PAHs) in wastewater samples after preconcentration by salting-out assisted liquid-liquid extraction was achieved using a doolittle multivariate calibration algorithm (DMCA). The DMCA was applied by lower and upper ...
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Simultaneous spectrophotometric determination of some polycyclic aromatic hydrocarbons (PAHs) in wastewater samples after preconcentration by salting-out assisted liquid-liquid extraction was achieved using a doolittle multivariate calibration algorithm (DMCA). The DMCA was applied by lower and upper (LU) triangular matrix decomposition which is efficient, powerful and easily. Results were shown that DMCA has advantages such as, simplicity, rapidness, avoiding matrix inverting and reducing the orders of matrices. The influence of various parameters, such as extraction solvent and volume, type and amount of salt, vortex time and sample pH were studied and optimized. The net analyte signal (NAS) method was used for calculating figures of merit. Linear range (LR) of calibration graphs for naphthalene, anthracene and pyrene were between 0.20 - 2.00, 0.10 - 1.50 and 0.07 -1.00 µg mL-1, respectively. The root mean square errors of prediction (RMSEP) for naphthalene, anthracene and pyrene using DMCA model were 0.0367, 0.0331 and 0.0305, respectively.
Suprapto Suprapto; Yessy I. Riwayati; Yatim L. Ni’mah
Abstract
In this study, the differential pulse voltammetry (DPV) method was used to simultaneously determine bismuth and copper concentrations. A 25 bismuth and copper mixtures at the designed ratio were measured using the DPV technique. However, the overlapping differential pulse voltammograms obtained made ...
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In this study, the differential pulse voltammetry (DPV) method was used to simultaneously determine bismuth and copper concentrations. A 25 bismuth and copper mixtures at the designed ratio were measured using the DPV technique. However, the overlapping differential pulse voltammograms obtained made it difficult to quantitatively analyze the concentrations based on adaptive peak current selection. To address this issue, the voltammograms were preprocessed using derivatization and peak subtraction. The second derivative voltammogram was found to be highly correlated with the copper-bismuth concentration ratio, resulting in improved fit and prediction accuracy. To further improve the accuracy and precision of the training and prediction results, XGBoost and Gradient Boosting regression models were applied. The XGBoost and Gradient Boosting regression models showed high accuracy and precision with r-squared values of 0.877 and 0.993 for copper, and 0.879 and 0.993 for bismuth, respectively. The mean recoveries of copper were 99.84% and 98.07%, while bismuth recoveries were 93.17% and 90.85% for XGBoost and Gradient Boosting, respectively. Additionally, cross-validation using 10 splits produced a mean score of 45.565 and a mean absolute error of 13.051 for copper, and a mean score of 13.600 and a mean absolute error of 10.920 for bismuth. Overall, the results indicate that the proposed method is an accurate and precise way to simultaneously determine bismuth and copper concentrations.
Asghar Amiri; Mohammad Rahimipour
Volume 3, Issue 1 , March 2016, , Pages 38-41
Abstract
In this research, poly (DL-lactide-co-glycolide)-block-poly (ethylene glycol), (PLGA-PEG) nanoparticles (NPs) of less than 195 nm in diameter containing of Naringenin (NRG) a naturally flavonoid were synthesized. Encapsulated form NRG improves its medical properties and solubility. The therapeutic efficacy ...
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In this research, poly (DL-lactide-co-glycolide)-block-poly (ethylene glycol), (PLGA-PEG) nanoparticles (NPs) of less than 195 nm in diameter containing of Naringenin (NRG) a naturally flavonoid were synthesized. Encapsulated form NRG improves its medical properties and solubility. The therapeutic efficacy of the encapsulated naringenin (NRG-NPs) and NRG on human lung epithelial (A549) and mouse mammary (4T1) carcinoma cells proliferation was determined by MTT assays. The cytotoxicity potency was rated as follows: NRG-NPs > NRG. The antioxidant effects of the NRG and NRG-NPs were also determined by FRAP method. Our results show that NRG-NPs are cytotoxic compounds for cancer cells and anti-cancer effect can be attributed to the presence of Fe chelatory and antioxidant effects of NRG-NPs.
Alankar Shrivastava
Volume 2, Issue 2 , September 2015, , Pages 77-99
Abstract
Benign Prostatic Hyperplasia generally affects males above fourty years of age and has significant effect in overall quality of life (QOL). This is one of the cause of millions of dollors in healthcare expenditure. Alpha one adrenoreceptor blockers are frequently used for the benign prostatic enlargement ...
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Benign Prostatic Hyperplasia generally affects males above fourty years of age and has significant effect in overall quality of life (QOL). This is one of the cause of millions of dollors in healthcare expenditure. Alpha one adrenoreceptor blockers are frequently used for the benign prostatic enlargement because of their significant effect on storage and voiding symptoms, QOL, flow rate and post void residual urine volume. The present study is review on the determination of three alpha one adrenoreceptor blockers Alfuzosin, Silodosin and Naftopidil in various matrices and combinations. This kind of literature is helpful for those scientists engaged in the determination of these drugs by supporting them in terms of current available literature is one platform so that they can decide the initial conditions of their research such as decisions of mobile phase, dilutions etc. This review article also helps scientists engaged in developing formulations of these drugs.
Mohammad Mazloum-Ardakani; Azimeh Mandegari; Alireza Khoshroo Khoshroo; Saeed Masoum; Hadi Kargar
Volume 3, Issue 2 , September 2016, , Pages 96-104
Abstract
In this work, response surface methodology in conjunction with central composite design for modeling and optimization of the influence of some process variables (polyvinyl chloride (F1), ionophore (F2), additive (F3) and plasticizer (F4) amounts), on the performance of polyvinyl chloride membrane lead ...
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In this work, response surface methodology in conjunction with central composite design for modeling and optimization of the influence of some process variables (polyvinyl chloride (F1), ionophore (F2), additive (F3) and plasticizer (F4) amounts), on the performance of polyvinyl chloride membrane lead (ІІ) ion-selective electrode is discussed. The slope of 29.1 ± 0.1 mV at the optimal amounts of polyvinyl chloride (0.0283 g), ionophore (0.0074 g), additive (0.002 g) and plasticizer (0.060 g) has been achieved. The electrode exhibited a linear potential response to lead (II) in the concentration range of 1.0 × 10-5 mol L-1 to 1.0 × 10-1 mol L-1 over pH range of 3.0 - 5.5. Greatly, the alternating current impedance technique was applied to investigate the response mechanism of the electrode. The results were obtained from electrochemical impedance spectroscopy shows a linear concentrations range of 1.0 × 10-6 mol L-1 to 1.0×10-1 mol L-1 and in comparison with potentiometry, the pH range increased to 2.5 − 6.0.
Nasrin Soltani; Hosein Salavati; Mehrnoosh Paziresh; A. Moghadasi
Volume 2, Issue 1 , March 2015, , Pages 22-35
Abstract
The corrosion inhibition characteristics of two synthesized Schiff bases, namely N, N´-bis(2-hydroxy-6-nitrobenzaldehyde) benzidine and N, N´-bis(salysylaldehyde) benzidine, on the mild steel corrosion in 2.0 M hydrochloric acid have been investigated by weight loss, potentiodynamic ...
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The corrosion inhibition characteristics of two synthesized Schiff bases, namely N, N´-bis(2-hydroxy-6-nitrobenzaldehyde) benzidine and N, N´-bis(salysylaldehyde) benzidine, on the mild steel corrosion in 2.0 M hydrochloric acid have been investigated by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy techniques. These studies were carried out at different concentrations, temperatures and durations. Polarization measurements indicate that the two inhibitors act as mixed type inhibitors. The adsorption of inhibitors obeys the Langmuir adsorption isotherm and the thermodynamic parameters (Ea, Kads, ΔG0ads) were calculated and discussed. Quantum chemical calculations were performed to provide further insight into the inhibition efficiencies determined experimentally.
Sedigheh Kamran
Volume 4, Issue 2 , September 2017, , Pages 22-32
Abstract
Fe3O4 magnetic nanoparticles modified with alizarin red S (ARS-Fe3O4) were used for the removal of several metal ions from aqueous solution. The mean size and the surface morphology of the nanoparticles were characterized by TEM, XRD and FTIR techniques. Adsorption studies of mentioned metal ions were ...
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Fe3O4 magnetic nanoparticles modified with alizarin red S (ARS-Fe3O4) were used for the removal of several metal ions from aqueous solution. The mean size and the surface morphology of the nanoparticles were characterized by TEM, XRD and FTIR techniques. Adsorption studies of mentioned metal ions were performed in batch system. The adsorption of metal ions onto ARS-Fe3O4nanoparticles was affected by the several analytical parameters such as an initial pH, metal ions concentration, adsorbent amount, contact time and temperature. Experimental results indicated that ARS-Fe3O4 nanoparticles were quantitatively removed. The maximum adsorption capacities ofARS-Fe3O4 for the Langmuir model were 50.0, 22.7 and 21.7 mg of metal ions per gram of nanoparticle for Zn2+,Cu2+and Pb2+, respectively. The isotherm evaluations revealed that the Langmuir model attained better fits to the equilibrium data than the othermodels. The kinetic data of adsorption of Zn2+,Cu2+and Pb2+ ions on the synthesized adsorbents were best described by pseudo-second-order equation. The adsorption processesfor three metal ions were endothermic. Metal ions were desorbed from nanoparticles by 2 mLHCl solution 0.1 mol L−1.
Nosrat Madadi Mahani; Azra Horzadeh
Volume 5, Issue 2 , September 2018, , Pages 23-30
Abstract
A quantitative structure activity relationship analysis has been applied to a data set of 34 derivatives of 8-hydroxy-2-iminochromene with inhibitory activities for carbonyl reductase 1. Semi-empirical quantum chemical calculations at the AM1 level were used to find the geometry of the studied molecules. ...
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A quantitative structure activity relationship analysis has been applied to a data set of 34 derivatives of 8-hydroxy-2-iminochromene with inhibitory activities for carbonyl reductase 1. Semi-empirical quantum chemical calculations at the AM1 level were used to find the geometry of the studied molecules. Whole numbers of descriptors were calculated with Dragon software, and a subset of calculated descriptors was selected from 407 Dragon descriptors with the multiple linear regression (MLR), partial least square and principal component analysis methods. Results displayed that the MLR method predicted of activity good enough. The best model of MLR, with seven descriptors was selected. Also it indicates very good consistency towards data variations for the validation methods. The predicted values of activities are in suitable agreement with the experimental results. The obtained results suggested that the PLS method could be more helpful to predict the biological activity of iminochromene derivatives. This study is be useful to predict the activity of other compounds in the same derivatives.
Bafe Baykedagn; Yared Merdassa; Abera Gure
Volume 4, Issue 1 , March 2017, , Pages 25-33
Abstract
In this study, vortex-assisted low density based dispersive liquid-liquid microextraction followed by high performance liquid chromatography with ultraviolet detector has been developed for the determination of three pesticides including chlorflurenol-methyl, chlorfenvinphos, and diazinon from environmental ...
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In this study, vortex-assisted low density based dispersive liquid-liquid microextraction followed by high performance liquid chromatography with ultraviolet detector has been developed for the determination of three pesticides including chlorflurenol-methyl, chlorfenvinphos, and diazinon from environmental water samples. Different parameters influencing the extraction efficiency such as the type and volume of extraction and disperser solvent, sample pH, salt addition as well as vortex and centrifugation time were investigated and the optimal conditions were obtained. Under the optimum conditions, the calibration curves were linear in the concentration range of 8.5–100, 3.1–100 and 36.5–600 ng/mL for chlorflurenol-Methyl, chlorfenvinphos and diazinon, respectively, with coefficient of determination (r2) of 0.993 or better. The limits of detection and quantification of the analytes, which were determined at 3 and 10 signal-to-noise ratio (S/N) ranged from 0.9–11 and 3.1–36.8 ng/mL, respectively. The proposed method has been successfully applied to the analysis of real water samples. The relative recoveries (%RR) studied at two spiking concentration levels were ranging from 76–108%, with the corresponding relative standard deviation (%RSD) ranging from 1.9–9.9%. The results of study demonstrated that the proposed method is efficient for extraction and/or preconcentration of the three pesticides prior to quantitative determination utilizing HPLC–UV/Vis instrument.
