SHAHAB SHARIATI - Academia.edu (original) (raw)
Papers by SHAHAB SHARIATI
Antimicrobial Resistance and Infection Control, Apr 25, 2023
Background The use of disinfectants and alcohol-based hand rubs (ABHR) to prevent COVID-19 transm... more Background The use of disinfectants and alcohol-based hand rubs (ABHR) to prevent COVID-19 transmission increased in the first wave of the infection. To meet the increased demand, the Iranian Ministry of Health issued an emergency use authorization allowing new manufacturers to enter the market, despite the limited capacity for surveillance of these products during COVID-19. Methanol poisoning outbreaks spread rapidly, and more people died from methanol poisoning than COVID-19 in some cities. The aim of this study was to analyze some ABHRs in the Iranian market to see if (a) ABHRs are standard and suitable for hand antisepsis and (b) contained potentially dangerous toxic alcohols. Method Between February and March 2020, 64 brands of ABHR were conveniently collected from pharmacies, supermarkets, and shops selling hygienic products and analyzed using Gas Chromatography. World Health Organization and Food and Drug Administration guidelines were used to define minimum requirements for ABHR. For estimating the risk for acute methanol poisoning, we assumed a serum methanol concentration of 200 mg/L following ABHR ingestion was sufficient to cause intoxication. This threshold concentration would be achieved in an average 75-kg adult after consuming 8000 mg (or eight grams) methanol in 1-2 h. Results The median [IQR] (range) concentration of ethanol, isopropanol, and methanol were 59% v/v [32.2, 68] (0, 99), 0 mg/L [0, 0] (0, 197,961), and 0 mg/L [0, 0] (0, 680,100), respectively. There was a strong negative correlation between methanol and ethanol contents of hand rubbers (r=-0.617, p < 0.001). Almost 47% of ABHRs complied with minimum standards. In 12.5% of ABHRs, high concentrations of methanol were observed, which have no antiseptic properties but could cause acute methanol poisoning if ingested. Conclusion COVID-19 initiated a policy for distribution and use of ABHR with little control. As ABHR and masks are still accepted preventive measures of the disease, non-standard ABHR compositions may increase the population's risk to both COVID-19 infection and methanol poisoning.
Fe 3 O 4 nanoparticles were prepared hydrothermally and characterized by X-Ray diffraction spectr... more Fe 3 O 4 nanoparticles were prepared hydrothermally and characterized by X-Ray diffraction spectroscopy (XRD), and scanning electron microscopy (SEM). It was found that these nanoparticles can act as an efficient catalyst in the degradation of Methylene blue dye in aqueous solution in a Fenton like system in presence of 30% perhydrol. Uv-Vis spectroscopy was used to determine the concentration of dye during optimization of different affecting factors such as pH, catalyst loading, and amount of the oxidant. Based on these results, 0.6 g/L of the catalyst and 0.32 mmol/L of the oxidant at pH=4.8 were selected as the optimum conditions and this resulted in a considerable degradation in less than 20 minutes. The catalyst was also found to be recyclable with no considerable decrease in its efficiency in successive runs.
ChemInform, Aug 16, 2012
ABSTRACT The reaction is conducted under environmentally benign conditions and has an easy work-u... more ABSTRACT The reaction is conducted under environmentally benign conditions and has an easy work-up procedure.
PubMed, Jun 1, 2011
In the present study, a simple and efficient extraction method based on dispersive liquid-liquid ... more In the present study, a simple and efficient extraction method based on dispersive liquid-liquid microextraction prior to UV-Vis spectrophotometry was developed for the preconcentration and determination of copper ions in environmental samples. Briefly, cupric ions (Cu II) were reduced to cuprous (Cu I) with addition of hydroxyl amine hydrochloride and formed hydrophobic chelates with neocuproine. Then, a proper mixture of acetonitrile (as dispersive solvent) and choloroform (as extraction solvent) was rapidly injected into the solution and a cloudy solution was formed. After centrifuging, choloroform was sedimented at the bottom of a conical tube and diluted with 100 µL of methanol for further UV-Vis spectrophotometry measurement. An orthogonal array design (OAD) was employed to study the effects of different parameters on the extraction efficiency. Under the optimum experimental conditions, a preconcentration factor up to 63.6 was achieved for extraction from 5.0 mL of sample solution. The limit of detection (LOD) based on S/N = 3 was 0.33 µg L-1 and the calibration curve was linear in the range of 1-200 µg L-1 with reasonable linearity (r2 > 0.997). Finally, the accuracy of the proposed method was successfully evaluated by determination of trace amounts of copper ions in different water samples and satisfactory results were obtained.
PubMed, Jun 1, 2012
The antiviral drugs that inhibit human immunodeficiency virus (HIV) entry to the target cells are... more The antiviral drugs that inhibit human immunodeficiency virus (HIV) entry to the target cells are already in different phases of clinical trials. They prevent viral entry and have a highly specific mechanism of action with a low toxicity profile. Few QSAR studies have been performed on this group of inhibitors. This study was performed to develop a quantitative structure-activity relationship (QSAR) model of the biological activity of indole glyoxamide derivatives as inhibitors of the interaction between HIV glycoprotein gp120 and host cell CD4 receptors. Forty different indole glyoxamide derivatives were selected as a sample set and geometrically optimized using Gaussian 98W. Different combinations of multiple linear regression (MLR), genetic algorithms (GA) and artificial neural networks (ANN) were then utilized to construct the QSAR models. These models were also utilized to select the most efficient subsets of descriptors in a cross-validation procedure for non-linear log (1/EC50) prediction. The results that were obtained using GA-ANN were compared with MLR-MLR and MLR-ANN models. A high predictive ability was observed for the MLR, MLR-ANN and GA-ANN models, with root mean sum square errors (RMSE) of 0.99, 0.91 and 0.67, respectively (N = 40). In summary, machine learning methods were highly effective in designing QSAR models when compared to statistical method.
Journal of Analytical Chemistry, Feb 1, 2020
A simple, sensitive and efficient method based on hollow fiber liquid phase microextraction follo... more A simple, sensitive and efficient method based on hollow fiber liquid phase microextraction followed by high performance liquid chromatography has been developed for preconcentration and determination of trace carbamazepine, an antiepileptic drug, in aqueous and biological solutions.The main parameters affecting the extraction efficiency were studied using response surface methodology. Central composite design was performed at five levels of extraction time, pH and ionic strength. The final model showed good linearity and performance. The optimal conditions were observed at 48.5 min, 8.9 and 0.29 M for extraction time, pH and ionic strength, respectively. The calibration curve was linear in the range of 5-500 μg/L with correlation coefficient of 0.9999 and limit of detection of 2.8 μg/L. Finally, the applicability of the proposed method was evaluated by extraction and determination of the drug in aqueous and plasma samples. The intraand inter-day coefficients of variation were less than 4.7 for all real samples.
![Research paper thumbnail of Synthesis, characterization, and catalytic application of Fe <sub>3</sub> O <sub>4</sub> ‐Si‐[CH <sub>2</sub> ] <sub>3</sub> ‐N=CH‐aryl for the efficient synthesis of novel poly‐substituted pyridines](https://attachments.academia-assets.com/118659881/thumbnails/1.jpg)
](Journal of The Chinese Chemical Society, Nov 15, 2018
In this paper, we have reported the synthesis of Au NPs-reduced graphene oxide (rGO) composites u... more In this paper, we have reported the synthesis of Au NPs-reduced graphene oxide (rGO) composites under microwave irradiation using ascorbic acid as eco-friendly reducing agent. The formation of Au NPs-rGO composites was confirmed by UV/Visible spectroscopy, DRIFT spectroscopy, TGA, XRD analysis, SAXS and HRTEM. HRTEM analysis results show that the particle size of the Au NPs formed on rGO nanosheets were in the range of 2-20 nm which is also supported by SAXS analysis results. The synthesized Au NPs-rGO composites were successfully utilized for the aerobic oxidation of benzyl alcohols to their corresponding aldehydes.
Journal of nanostructure in chemistry, Jan 23, 2019
In this research, the synthesis of a suitable nanocomposite in terms of properties and economics ... more In this research, the synthesis of a suitable nanocomposite in terms of properties and economics for use in bipolar plates in proton-exchange membrane fuel cells (PEMFCs) has been carried out successfully. Nowadays, bipolar plates play a significant role in fuel cells which is absolutely important in renewable energy industry. So, epoxy/graphite/nano-copper nanocomposite bipolar plates are prepared by bulk molding compound process. Graphite and nano-copper were added as primary and secondary fillers to the composite, respectively. Epoxy resin was selected since fabrication bulk molding can be done with ease and also because of its lower cost compared to other materials. Although graphite could increase conductive characteristics, it is not sufficient for bipolar plates. Therefore, we boost the conductive properties by increasing nano-copper. Due to the small size of nanoscale copper, it can be well dispersed in polymer and graphite matrix; nano-copper can release conductive properties perfectly throughout the composite. Different percentages of nano-copper, graphite and constant percentage of epoxy are used for this purpose. The electrical resistance, flexural strength, and density of composites were measured according to the applicable standards. The morphology of the prepared plate was studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD) found that fillers disperse well in the matrix. Innovations in this work include improving properties and increasing the efficiency of the nanocomposite by adding metal nanoparticles (copper).
Analytical Methods
Cu electrode was modified by azolla and magnetite azolla powders to produce impedimetric biosenso... more Cu electrode was modified by azolla and magnetite azolla powders to produce impedimetric biosensors. Injection of PAE blockers to these biosensors obtained a linear relationship between ΔRCT and log CPAEs with good sensitivity and repeatability.
RSC Advances, 2020
Multi-walled carbon nanotubes (MWNTs) were modified with carboxylic acid functional groups (MWCNT... more Multi-walled carbon nanotubes (MWNTs) were modified with carboxylic acid functional groups (MWCNTs-(COOH) n) prior to decoration with Fe 3 O 4 nanoparticles. A further modification step by polyethyleneimine (PEI) resulted in Fe 3 O 4-MWCNTs@PEI which provided a suitable platform for coordination and in situ reduction of silver ions to obtain an Fe 3 O 4-MWCNTs@PEI-Ag nanocomposite with highly dispersed Ag nanoparticles. The Fe 3 O 4-MWCNTs@PEI-Ag hybrid material was characterized by various techniques such as Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA), and was used as an efficient catalyst for chemoselective reduction of nitroaromatic and nitrile compounds to their corresponding amines in aqueous solution at ambient temperature. Nitrofurazone, a cytotoxic antibiotic, as a non-aromatic example was also reduced selectively at the nitro group without reduction of the other functionalities in the presence of Fe 3 O 4-MWCNTs@PEI-Ag. The catalyst was magnetically recoverable and maintained its activity for at least six cycles without considerable loss of efficiency.
Synthesis and Reactivity in Inorganic Metal-organic and Nano-metal Chemistry, Dec 15, 2015
In the present study, simple and versatile methods for preparation of SBA-3, SBA-15, and KIT-6 me... more In the present study, simple and versatile methods for preparation of SBA-3, SBA-15, and KIT-6 mesoporous silica magnetite nanoparticles (Fe3O4@SBA and Fe3O4@KIT-6 MNPs) were developed. The chemically synthesized magnetite nanoparticles were utilized for preparation of mesoporous MNPs with Fe3O4 core and mesoporous silica (SBA-3, SBA-15, and KIT-6) shell. The size and chemical structures of the synthesized nanoparticles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectrophotometery (FT-IR). The synthesized mesoporous MNPs showed super paramagnetic property and the surface area of synthesized Fe3O4@SBA-3, Fe3O4@SBA-15, and Fe3O4@KIT-6 via BET was obtained as 627.87, 510.95, and 241.68 m2 g−1, respectively.
Journal of Chemical Health Risks, May 1, 2021
Analytical and Bioanalytical Chemistry Research, Jul 1, 2020
In the present study, hollow fiber liquid-phase microextraction (HF-LPME) method was used to prec... more In the present study, hollow fiber liquid-phase microextraction (HF-LPME) method was used to preconcentrate trace amount of phenol prior to its spectrophotometric determination. Phenol reacted with 4-aminoantipyrine (4-AAP) reagent in presence of potassium hexacyanoferrate(III) and then was extracted into the octanol extractant inserted into the lumen and pores of hollow fibers. Some factors such as concentrations of 4-aminoantipyrine, potassium hexacyanoferrate(III) and ammonium chloride, the rate of stirring, and extraction time were optimized using response surface method based on the central composite design (CCD). Under the optimum conditions, the limit of detection (LOD) and limit of quantification (LOQ) were obtained as 1.5 and 5 μg l-1 , respectively. Also, the relative standard deviation (RSD%) and enrichment factor (EF) were obtained as 4.9% and 174, respectively. In addition, the suggested method was implemented to measure the phenol concentration in some real samples, including wastewater of wood and textile factories, as well as the extracts of mint, and green tea. The accuracy was investigated by the recovery of phenol from real samples in the range of 82.3-112%. The results showed that the proposed method is simple, rapid, eco-friendly, and accurate for preconcentration and analysis of phenol.
RSC Advances, 2021
In this work, a sensitive and efficient voltammetric biosensor was introduced for differential pu... more In this work, a sensitive and efficient voltammetric biosensor was introduced for differential pulse voltammetric (DPV) determination of some phthalic acid esters (PAEs) including dibutyl phthalate (DBP), dimethyl phthalate (DMP), di(2-ethylhexyl)phthalate (DEHP) and dicyclohexyl phthalate (DCHP) in aqueous solutions. Briefly, the surface of a copper electrode was modified by azolla paste prepared using azolla powder and electroencephalography gel (EEG). The modified surface was characterized by electrochemical impedance spectroscopy (EIS), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET) analysis and energy dispersive X-ray (EDX) methods. Determination of PAEs was conducted based on their blocking effect on the electrode surface for ferrous ion oxidation. The central composite design (CCD) was conducted to optimize the effects of four experimental parameters including the concentration of Fe 2+ ions (C Fe 2+) and supporting electrolyte (C sup. elec), solution pH and modifier/gel mass ratio on the decrease in the anodic peak current of ferrous ions as the response. Predicted optimal conditions (C Fe 2+ ¼ 319 mM, C sup. elec ¼ 0.125 M, pH ¼ 7.52 and modifier/gel mass ratio ¼ 0.19) were validated by experimental checking which resulted in an error of 1.453%. At the optimum conditions, linear relationships were found between the DPV responses and PAEs concentrations and the limit of detection (LOD) and limit of quantification (LOQ) values were in the ranges of 0.2-0.4 mg L À1 and 0.5-1.0 mg L À1 , respectively. Good recovery percentages ranging from 97.3 to 100.3% with RSD < 3.2% suggested the proposed method for efficient, accurate and quick determination of PAEs in real water samples.
Journal of Heterocyclic Chemistry, Oct 7, 2020
Fe3O4 magnetic nanoparticles were synthesized and functionalized by propylsilan and after that ar... more Fe3O4 magnetic nanoparticles were synthesized and functionalized by propylsilan and after that arginine. The synthesized Fe3O4@PS‐Arginine magnetic nanoparticles were modified to obtain Fe3O4@PS‐Arg[HSO4]. These nanoparticles were used as environmental friendly solidacid magnetic nanocatalyst for the synthesis of 2‐amino‐4‐arylbenzo[h]quinoline‐3‐carbonitrile and 10,10‐dimethyl‐7‐aryl‐9,10,11,12‐tetrahydrobenzo[c]acridin‐8(7H)‐one derivatives via the one‐pot reaction of α‐naphthilamine and aromatic aldehydes with malononitrile or dimedone. Simple operation, high reaction yields, reusability of catalyst for several times, short reaction time and easy separation from reaction mixture are the key advantages of using this catalyst.
Research on Chemical Intermediates, Oct 23, 2021
Fe3O4@SiO2-(CH2)3-NH-Asn-Cu(II) was synthesized via functionalization of synthesized Fe3O4 with 3... more Fe3O4@SiO2-(CH2)3-NH-Asn-Cu(II) was synthesized via functionalization of synthesized Fe3O4 with 3-aminopropyltriethoxysilane, asparagine, and Cu(OAc)2. The prepared magnetic nanocatalyst was used as a green and efficient catalyst for the synthesis of chromeno-pyrazolo[1,2-b]phthalazine-6,9,14(7H)-trione derivatives by reaction of aldehydes, phthalhydrazide, and 4-hydroxycoumarin in short reaction times and good yields. The magnetic nature of the catalyst led to easy and convenient separation by an external magnet and reused for 5 consecutive runs without significant loss inactivity. The structure of the catalyst was characterized by FT-IR, SEM, EDX, VSM analyses.
Arabian Journal of Chemistry, Sep 1, 2016
In this work, quantitative structure-activity relationship (QSAR) study has been done on tricycli... more In this work, quantitative structure-activity relationship (QSAR) study has been done on tricyclic phthalimide analogues acting as HIV-1 integrase inhibitors. Forty compounds were used in this study. Genetic algorithm (GA), artificial neural network (ANN) and multiple linear regressions (MLR) were utilized to construct the non-linear and linear QSAR models. It revealed that the GA-ANN model was much better than other models. For this purpose, ab initio geometry optimization performed at B3LYP level with a known basis set 6-31G (d). Hyperchem, ChemOffice and Gaussian 98W softwares were used for geometry optimization of the molecules and calculation of the quantum chemical descriptors. To include some of the correlation energy, the calculation was done with the density functional theory (DFT) with the same basis set and Becke's three parameter hybrid functional using the LYP correlation functional (B3LYP/6-31G (d)). For the calculations in solution phase, the polarized continuum model (PCM) was used and also included optimizations at gas-phase B3LYP/6-31G (d) level for comparison. In the aqueous phase, the root-mean-square errors of the training set and the test set for GA-ANN model using jack-knife method, were 0.1409, 0.1804, respectively. In the gas phase, the
Substance Abuse Treatment Prevention and Policy, Dec 1, 2019
Background: Methanol is highly toxic to human beings and naturally exists in some beverages. Havi... more Background: Methanol is highly toxic to human beings and naturally exists in some beverages. Having access to an easy and cheap method for its determination is of great importance to increase the safety of use of these beverages. Our main aim is to evaluate methanol concentration of some alcoholic beverages in Iran black market and compare it with the European and US standards. Also, we evaluated the efficacy of a newly designed and produced chemical kit in determining the risk of methanol toxicity by drinking of such samples compared to gas chromatography method. Methods: Methanol content of suspected alcoholic beverages referred to forensic toxicology laboratory, Guilan province, Iran was measured using gas chromatography and a recently designed kit based on modified colorimetric chromotropic acid method. Results: Of 1221 samples, 145 (11.9%) had no ethanol content, while in three samples (0.25%), methanol was high enough (700,000; 870,000; 920,000 mg/L) to cause severe methanol toxicity. Median [IQR] ethanol content of the suspected samples was 9% [3.7, 32.75]. Methanol was detected in 128 (10.48%) samples using gas chromatography method and 160 samples (13.1%) with designed kit with 100% sensitivity, 97.07% specificity, and 100% negativepredictive-value. Conclusions: Alcoholic beverages produced in local black market in Iran are not safe at all. The application of the new method is practical, rapid, easy, and accurate to evaluate the risk of methanol toxicity in suspected alcoholic drinks.
Journal of Porous Materials, Jul 19, 2016
In this research, novel nanoparticles of Kit-6 mesoporous silica magnetite were synthesized with ... more In this research, novel nanoparticles of Kit-6 mesoporous silica magnetite were synthesized with 9.6 nm pore diameter and 241.68 m 2 g-1 surface area. The synthesized mesoporous magnetite nanoparticles (MMNPs) were functionalized with amine groups. Scanning electron microscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy and nitrogen adsorption-desorption method confirmed the morphology and structure of the synthesized nanoparticles. The amine functionalized MMNPs were used for sorption of toxic chromate ions from aqueous samples. The effect of various experimental parameters (four factors at three levels) on the sorption efficiency of Cr(VI) was studied and optimized via Taguchi L 9 (3 4) orthogonal array experimental design. At optimum conditions, the sorption of the Cr(VI) was best described by a pseudo second-order kinetic model with R 2 = 0.9999 and q eq = 129.8 mg g-1 , suggesting chemisorption mechanism. Adsorption data were fitted well to the Langmuir isotherm and the synthesized sorbent showed complete ion removal with 185.2 mg g-1 sorption capacity.
Journal of Advances in Environmental Health Research, Jul 1, 2022
Background: Microbial resistance to antibiotics has led to serious efforts to discover novel drug... more Background: Microbial resistance to antibiotics has led to serious efforts to discover novel drugs, which is why there is so much interest in the use of herbs. Therefore, the aim of this study was to investigate the antibacterial effect of aqueous, hydro-alcoholic, and alcoholic extracts of Morus nigra in comparison with some common antibiotics. Method: In this experimental study, the zone of inhibition, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the Morus nigra extracts against Staphylococcus epidermidis, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus mutans and Streptococcus pyogenes were determined using the disk diffusion and broth macro-dilution methods. Statistical analysis was performed using the ANOVA test by SPSS software. Results: The results of this study showed that all studied strains were sensitive to different extracts of Morus nigra. The highest antibacterial effect was related to the aqueous extract of Morus nigra, which created an inhibition zone with a diameter of 22.25 against Streptococcus mutans and Streptococcus pyogenes. The lowest inhibition zone (9 mm) was related to the alcoholic extract of Morus nigra against Pseudomonas aeruginosa. The MIC values of different extracts of Morus nigra against test bacteria varied from 0.78 to 3.12 mg/ml and MBC values were between 3.12 and 50 mg/mL. Conclusion: Based on the findings of this study, the aqueous extract of Morus nigra has shown strong bactericidal properties against all studied bacterial strains, which indicates its potential for therapeutic application.
Antimicrobial Resistance and Infection Control, Apr 25, 2023
Background The use of disinfectants and alcohol-based hand rubs (ABHR) to prevent COVID-19 transm... more Background The use of disinfectants and alcohol-based hand rubs (ABHR) to prevent COVID-19 transmission increased in the first wave of the infection. To meet the increased demand, the Iranian Ministry of Health issued an emergency use authorization allowing new manufacturers to enter the market, despite the limited capacity for surveillance of these products during COVID-19. Methanol poisoning outbreaks spread rapidly, and more people died from methanol poisoning than COVID-19 in some cities. The aim of this study was to analyze some ABHRs in the Iranian market to see if (a) ABHRs are standard and suitable for hand antisepsis and (b) contained potentially dangerous toxic alcohols. Method Between February and March 2020, 64 brands of ABHR were conveniently collected from pharmacies, supermarkets, and shops selling hygienic products and analyzed using Gas Chromatography. World Health Organization and Food and Drug Administration guidelines were used to define minimum requirements for ABHR. For estimating the risk for acute methanol poisoning, we assumed a serum methanol concentration of 200 mg/L following ABHR ingestion was sufficient to cause intoxication. This threshold concentration would be achieved in an average 75-kg adult after consuming 8000 mg (or eight grams) methanol in 1-2 h. Results The median [IQR] (range) concentration of ethanol, isopropanol, and methanol were 59% v/v [32.2, 68] (0, 99), 0 mg/L [0, 0] (0, 197,961), and 0 mg/L [0, 0] (0, 680,100), respectively. There was a strong negative correlation between methanol and ethanol contents of hand rubbers (r=-0.617, p < 0.001). Almost 47% of ABHRs complied with minimum standards. In 12.5% of ABHRs, high concentrations of methanol were observed, which have no antiseptic properties but could cause acute methanol poisoning if ingested. Conclusion COVID-19 initiated a policy for distribution and use of ABHR with little control. As ABHR and masks are still accepted preventive measures of the disease, non-standard ABHR compositions may increase the population's risk to both COVID-19 infection and methanol poisoning.
Fe 3 O 4 nanoparticles were prepared hydrothermally and characterized by X-Ray diffraction spectr... more Fe 3 O 4 nanoparticles were prepared hydrothermally and characterized by X-Ray diffraction spectroscopy (XRD), and scanning electron microscopy (SEM). It was found that these nanoparticles can act as an efficient catalyst in the degradation of Methylene blue dye in aqueous solution in a Fenton like system in presence of 30% perhydrol. Uv-Vis spectroscopy was used to determine the concentration of dye during optimization of different affecting factors such as pH, catalyst loading, and amount of the oxidant. Based on these results, 0.6 g/L of the catalyst and 0.32 mmol/L of the oxidant at pH=4.8 were selected as the optimum conditions and this resulted in a considerable degradation in less than 20 minutes. The catalyst was also found to be recyclable with no considerable decrease in its efficiency in successive runs.
ChemInform, Aug 16, 2012
ABSTRACT The reaction is conducted under environmentally benign conditions and has an easy work-u... more ABSTRACT The reaction is conducted under environmentally benign conditions and has an easy work-up procedure.
PubMed, Jun 1, 2011
In the present study, a simple and efficient extraction method based on dispersive liquid-liquid ... more In the present study, a simple and efficient extraction method based on dispersive liquid-liquid microextraction prior to UV-Vis spectrophotometry was developed for the preconcentration and determination of copper ions in environmental samples. Briefly, cupric ions (Cu II) were reduced to cuprous (Cu I) with addition of hydroxyl amine hydrochloride and formed hydrophobic chelates with neocuproine. Then, a proper mixture of acetonitrile (as dispersive solvent) and choloroform (as extraction solvent) was rapidly injected into the solution and a cloudy solution was formed. After centrifuging, choloroform was sedimented at the bottom of a conical tube and diluted with 100 µL of methanol for further UV-Vis spectrophotometry measurement. An orthogonal array design (OAD) was employed to study the effects of different parameters on the extraction efficiency. Under the optimum experimental conditions, a preconcentration factor up to 63.6 was achieved for extraction from 5.0 mL of sample solution. The limit of detection (LOD) based on S/N = 3 was 0.33 µg L-1 and the calibration curve was linear in the range of 1-200 µg L-1 with reasonable linearity (r2 > 0.997). Finally, the accuracy of the proposed method was successfully evaluated by determination of trace amounts of copper ions in different water samples and satisfactory results were obtained.
PubMed, Jun 1, 2012
The antiviral drugs that inhibit human immunodeficiency virus (HIV) entry to the target cells are... more The antiviral drugs that inhibit human immunodeficiency virus (HIV) entry to the target cells are already in different phases of clinical trials. They prevent viral entry and have a highly specific mechanism of action with a low toxicity profile. Few QSAR studies have been performed on this group of inhibitors. This study was performed to develop a quantitative structure-activity relationship (QSAR) model of the biological activity of indole glyoxamide derivatives as inhibitors of the interaction between HIV glycoprotein gp120 and host cell CD4 receptors. Forty different indole glyoxamide derivatives were selected as a sample set and geometrically optimized using Gaussian 98W. Different combinations of multiple linear regression (MLR), genetic algorithms (GA) and artificial neural networks (ANN) were then utilized to construct the QSAR models. These models were also utilized to select the most efficient subsets of descriptors in a cross-validation procedure for non-linear log (1/EC50) prediction. The results that were obtained using GA-ANN were compared with MLR-MLR and MLR-ANN models. A high predictive ability was observed for the MLR, MLR-ANN and GA-ANN models, with root mean sum square errors (RMSE) of 0.99, 0.91 and 0.67, respectively (N = 40). In summary, machine learning methods were highly effective in designing QSAR models when compared to statistical method.
Journal of Analytical Chemistry, Feb 1, 2020
A simple, sensitive and efficient method based on hollow fiber liquid phase microextraction follo... more A simple, sensitive and efficient method based on hollow fiber liquid phase microextraction followed by high performance liquid chromatography has been developed for preconcentration and determination of trace carbamazepine, an antiepileptic drug, in aqueous and biological solutions.The main parameters affecting the extraction efficiency were studied using response surface methodology. Central composite design was performed at five levels of extraction time, pH and ionic strength. The final model showed good linearity and performance. The optimal conditions were observed at 48.5 min, 8.9 and 0.29 M for extraction time, pH and ionic strength, respectively. The calibration curve was linear in the range of 5-500 μg/L with correlation coefficient of 0.9999 and limit of detection of 2.8 μg/L. Finally, the applicability of the proposed method was evaluated by extraction and determination of the drug in aqueous and plasma samples. The intraand inter-day coefficients of variation were less than 4.7 for all real samples.
Journal of The Chinese Chemical Society, Nov 15, 2018
In this paper, we have reported the synthesis of Au NPs-reduced graphene oxide (rGO) composites u... more In this paper, we have reported the synthesis of Au NPs-reduced graphene oxide (rGO) composites under microwave irradiation using ascorbic acid as eco-friendly reducing agent. The formation of Au NPs-rGO composites was confirmed by UV/Visible spectroscopy, DRIFT spectroscopy, TGA, XRD analysis, SAXS and HRTEM. HRTEM analysis results show that the particle size of the Au NPs formed on rGO nanosheets were in the range of 2-20 nm which is also supported by SAXS analysis results. The synthesized Au NPs-rGO composites were successfully utilized for the aerobic oxidation of benzyl alcohols to their corresponding aldehydes.
Journal of nanostructure in chemistry, Jan 23, 2019
In this research, the synthesis of a suitable nanocomposite in terms of properties and economics ... more In this research, the synthesis of a suitable nanocomposite in terms of properties and economics for use in bipolar plates in proton-exchange membrane fuel cells (PEMFCs) has been carried out successfully. Nowadays, bipolar plates play a significant role in fuel cells which is absolutely important in renewable energy industry. So, epoxy/graphite/nano-copper nanocomposite bipolar plates are prepared by bulk molding compound process. Graphite and nano-copper were added as primary and secondary fillers to the composite, respectively. Epoxy resin was selected since fabrication bulk molding can be done with ease and also because of its lower cost compared to other materials. Although graphite could increase conductive characteristics, it is not sufficient for bipolar plates. Therefore, we boost the conductive properties by increasing nano-copper. Due to the small size of nanoscale copper, it can be well dispersed in polymer and graphite matrix; nano-copper can release conductive properties perfectly throughout the composite. Different percentages of nano-copper, graphite and constant percentage of epoxy are used for this purpose. The electrical resistance, flexural strength, and density of composites were measured according to the applicable standards. The morphology of the prepared plate was studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD) found that fillers disperse well in the matrix. Innovations in this work include improving properties and increasing the efficiency of the nanocomposite by adding metal nanoparticles (copper).
Analytical Methods
Cu electrode was modified by azolla and magnetite azolla powders to produce impedimetric biosenso... more Cu electrode was modified by azolla and magnetite azolla powders to produce impedimetric biosensors. Injection of PAE blockers to these biosensors obtained a linear relationship between ΔRCT and log CPAEs with good sensitivity and repeatability.
RSC Advances, 2020
Multi-walled carbon nanotubes (MWNTs) were modified with carboxylic acid functional groups (MWCNT... more Multi-walled carbon nanotubes (MWNTs) were modified with carboxylic acid functional groups (MWCNTs-(COOH) n) prior to decoration with Fe 3 O 4 nanoparticles. A further modification step by polyethyleneimine (PEI) resulted in Fe 3 O 4-MWCNTs@PEI which provided a suitable platform for coordination and in situ reduction of silver ions to obtain an Fe 3 O 4-MWCNTs@PEI-Ag nanocomposite with highly dispersed Ag nanoparticles. The Fe 3 O 4-MWCNTs@PEI-Ag hybrid material was characterized by various techniques such as Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA), and was used as an efficient catalyst for chemoselective reduction of nitroaromatic and nitrile compounds to their corresponding amines in aqueous solution at ambient temperature. Nitrofurazone, a cytotoxic antibiotic, as a non-aromatic example was also reduced selectively at the nitro group without reduction of the other functionalities in the presence of Fe 3 O 4-MWCNTs@PEI-Ag. The catalyst was magnetically recoverable and maintained its activity for at least six cycles without considerable loss of efficiency.
Synthesis and Reactivity in Inorganic Metal-organic and Nano-metal Chemistry, Dec 15, 2015
In the present study, simple and versatile methods for preparation of SBA-3, SBA-15, and KIT-6 me... more In the present study, simple and versatile methods for preparation of SBA-3, SBA-15, and KIT-6 mesoporous silica magnetite nanoparticles (Fe3O4@SBA and Fe3O4@KIT-6 MNPs) were developed. The chemically synthesized magnetite nanoparticles were utilized for preparation of mesoporous MNPs with Fe3O4 core and mesoporous silica (SBA-3, SBA-15, and KIT-6) shell. The size and chemical structures of the synthesized nanoparticles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectrophotometery (FT-IR). The synthesized mesoporous MNPs showed super paramagnetic property and the surface area of synthesized Fe3O4@SBA-3, Fe3O4@SBA-15, and Fe3O4@KIT-6 via BET was obtained as 627.87, 510.95, and 241.68 m2 g−1, respectively.
Journal of Chemical Health Risks, May 1, 2021
Analytical and Bioanalytical Chemistry Research, Jul 1, 2020
In the present study, hollow fiber liquid-phase microextraction (HF-LPME) method was used to prec... more In the present study, hollow fiber liquid-phase microextraction (HF-LPME) method was used to preconcentrate trace amount of phenol prior to its spectrophotometric determination. Phenol reacted with 4-aminoantipyrine (4-AAP) reagent in presence of potassium hexacyanoferrate(III) and then was extracted into the octanol extractant inserted into the lumen and pores of hollow fibers. Some factors such as concentrations of 4-aminoantipyrine, potassium hexacyanoferrate(III) and ammonium chloride, the rate of stirring, and extraction time were optimized using response surface method based on the central composite design (CCD). Under the optimum conditions, the limit of detection (LOD) and limit of quantification (LOQ) were obtained as 1.5 and 5 μg l-1 , respectively. Also, the relative standard deviation (RSD%) and enrichment factor (EF) were obtained as 4.9% and 174, respectively. In addition, the suggested method was implemented to measure the phenol concentration in some real samples, including wastewater of wood and textile factories, as well as the extracts of mint, and green tea. The accuracy was investigated by the recovery of phenol from real samples in the range of 82.3-112%. The results showed that the proposed method is simple, rapid, eco-friendly, and accurate for preconcentration and analysis of phenol.
RSC Advances, 2021
In this work, a sensitive and efficient voltammetric biosensor was introduced for differential pu... more In this work, a sensitive and efficient voltammetric biosensor was introduced for differential pulse voltammetric (DPV) determination of some phthalic acid esters (PAEs) including dibutyl phthalate (DBP), dimethyl phthalate (DMP), di(2-ethylhexyl)phthalate (DEHP) and dicyclohexyl phthalate (DCHP) in aqueous solutions. Briefly, the surface of a copper electrode was modified by azolla paste prepared using azolla powder and electroencephalography gel (EEG). The modified surface was characterized by electrochemical impedance spectroscopy (EIS), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET) analysis and energy dispersive X-ray (EDX) methods. Determination of PAEs was conducted based on their blocking effect on the electrode surface for ferrous ion oxidation. The central composite design (CCD) was conducted to optimize the effects of four experimental parameters including the concentration of Fe 2+ ions (C Fe 2+) and supporting electrolyte (C sup. elec), solution pH and modifier/gel mass ratio on the decrease in the anodic peak current of ferrous ions as the response. Predicted optimal conditions (C Fe 2+ ¼ 319 mM, C sup. elec ¼ 0.125 M, pH ¼ 7.52 and modifier/gel mass ratio ¼ 0.19) were validated by experimental checking which resulted in an error of 1.453%. At the optimum conditions, linear relationships were found between the DPV responses and PAEs concentrations and the limit of detection (LOD) and limit of quantification (LOQ) values were in the ranges of 0.2-0.4 mg L À1 and 0.5-1.0 mg L À1 , respectively. Good recovery percentages ranging from 97.3 to 100.3% with RSD < 3.2% suggested the proposed method for efficient, accurate and quick determination of PAEs in real water samples.
Journal of Heterocyclic Chemistry, Oct 7, 2020
Fe3O4 magnetic nanoparticles were synthesized and functionalized by propylsilan and after that ar... more Fe3O4 magnetic nanoparticles were synthesized and functionalized by propylsilan and after that arginine. The synthesized Fe3O4@PS‐Arginine magnetic nanoparticles were modified to obtain Fe3O4@PS‐Arg[HSO4]. These nanoparticles were used as environmental friendly solidacid magnetic nanocatalyst for the synthesis of 2‐amino‐4‐arylbenzo[h]quinoline‐3‐carbonitrile and 10,10‐dimethyl‐7‐aryl‐9,10,11,12‐tetrahydrobenzo[c]acridin‐8(7H)‐one derivatives via the one‐pot reaction of α‐naphthilamine and aromatic aldehydes with malononitrile or dimedone. Simple operation, high reaction yields, reusability of catalyst for several times, short reaction time and easy separation from reaction mixture are the key advantages of using this catalyst.
Research on Chemical Intermediates, Oct 23, 2021
Fe3O4@SiO2-(CH2)3-NH-Asn-Cu(II) was synthesized via functionalization of synthesized Fe3O4 with 3... more Fe3O4@SiO2-(CH2)3-NH-Asn-Cu(II) was synthesized via functionalization of synthesized Fe3O4 with 3-aminopropyltriethoxysilane, asparagine, and Cu(OAc)2. The prepared magnetic nanocatalyst was used as a green and efficient catalyst for the synthesis of chromeno-pyrazolo[1,2-b]phthalazine-6,9,14(7H)-trione derivatives by reaction of aldehydes, phthalhydrazide, and 4-hydroxycoumarin in short reaction times and good yields. The magnetic nature of the catalyst led to easy and convenient separation by an external magnet and reused for 5 consecutive runs without significant loss inactivity. The structure of the catalyst was characterized by FT-IR, SEM, EDX, VSM analyses.
Arabian Journal of Chemistry, Sep 1, 2016
In this work, quantitative structure-activity relationship (QSAR) study has been done on tricycli... more In this work, quantitative structure-activity relationship (QSAR) study has been done on tricyclic phthalimide analogues acting as HIV-1 integrase inhibitors. Forty compounds were used in this study. Genetic algorithm (GA), artificial neural network (ANN) and multiple linear regressions (MLR) were utilized to construct the non-linear and linear QSAR models. It revealed that the GA-ANN model was much better than other models. For this purpose, ab initio geometry optimization performed at B3LYP level with a known basis set 6-31G (d). Hyperchem, ChemOffice and Gaussian 98W softwares were used for geometry optimization of the molecules and calculation of the quantum chemical descriptors. To include some of the correlation energy, the calculation was done with the density functional theory (DFT) with the same basis set and Becke's three parameter hybrid functional using the LYP correlation functional (B3LYP/6-31G (d)). For the calculations in solution phase, the polarized continuum model (PCM) was used and also included optimizations at gas-phase B3LYP/6-31G (d) level for comparison. In the aqueous phase, the root-mean-square errors of the training set and the test set for GA-ANN model using jack-knife method, were 0.1409, 0.1804, respectively. In the gas phase, the
Substance Abuse Treatment Prevention and Policy, Dec 1, 2019
Background: Methanol is highly toxic to human beings and naturally exists in some beverages. Havi... more Background: Methanol is highly toxic to human beings and naturally exists in some beverages. Having access to an easy and cheap method for its determination is of great importance to increase the safety of use of these beverages. Our main aim is to evaluate methanol concentration of some alcoholic beverages in Iran black market and compare it with the European and US standards. Also, we evaluated the efficacy of a newly designed and produced chemical kit in determining the risk of methanol toxicity by drinking of such samples compared to gas chromatography method. Methods: Methanol content of suspected alcoholic beverages referred to forensic toxicology laboratory, Guilan province, Iran was measured using gas chromatography and a recently designed kit based on modified colorimetric chromotropic acid method. Results: Of 1221 samples, 145 (11.9%) had no ethanol content, while in three samples (0.25%), methanol was high enough (700,000; 870,000; 920,000 mg/L) to cause severe methanol toxicity. Median [IQR] ethanol content of the suspected samples was 9% [3.7, 32.75]. Methanol was detected in 128 (10.48%) samples using gas chromatography method and 160 samples (13.1%) with designed kit with 100% sensitivity, 97.07% specificity, and 100% negativepredictive-value. Conclusions: Alcoholic beverages produced in local black market in Iran are not safe at all. The application of the new method is practical, rapid, easy, and accurate to evaluate the risk of methanol toxicity in suspected alcoholic drinks.
Journal of Porous Materials, Jul 19, 2016
In this research, novel nanoparticles of Kit-6 mesoporous silica magnetite were synthesized with ... more In this research, novel nanoparticles of Kit-6 mesoporous silica magnetite were synthesized with 9.6 nm pore diameter and 241.68 m 2 g-1 surface area. The synthesized mesoporous magnetite nanoparticles (MMNPs) were functionalized with amine groups. Scanning electron microscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy and nitrogen adsorption-desorption method confirmed the morphology and structure of the synthesized nanoparticles. The amine functionalized MMNPs were used for sorption of toxic chromate ions from aqueous samples. The effect of various experimental parameters (four factors at three levels) on the sorption efficiency of Cr(VI) was studied and optimized via Taguchi L 9 (3 4) orthogonal array experimental design. At optimum conditions, the sorption of the Cr(VI) was best described by a pseudo second-order kinetic model with R 2 = 0.9999 and q eq = 129.8 mg g-1 , suggesting chemisorption mechanism. Adsorption data were fitted well to the Langmuir isotherm and the synthesized sorbent showed complete ion removal with 185.2 mg g-1 sorption capacity.
Journal of Advances in Environmental Health Research, Jul 1, 2022
Background: Microbial resistance to antibiotics has led to serious efforts to discover novel drug... more Background: Microbial resistance to antibiotics has led to serious efforts to discover novel drugs, which is why there is so much interest in the use of herbs. Therefore, the aim of this study was to investigate the antibacterial effect of aqueous, hydro-alcoholic, and alcoholic extracts of Morus nigra in comparison with some common antibiotics. Method: In this experimental study, the zone of inhibition, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the Morus nigra extracts against Staphylococcus epidermidis, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus mutans and Streptococcus pyogenes were determined using the disk diffusion and broth macro-dilution methods. Statistical analysis was performed using the ANOVA test by SPSS software. Results: The results of this study showed that all studied strains were sensitive to different extracts of Morus nigra. The highest antibacterial effect was related to the aqueous extract of Morus nigra, which created an inhibition zone with a diameter of 22.25 against Streptococcus mutans and Streptococcus pyogenes. The lowest inhibition zone (9 mm) was related to the alcoholic extract of Morus nigra against Pseudomonas aeruginosa. The MIC values of different extracts of Morus nigra against test bacteria varied from 0.78 to 3.12 mg/ml and MBC values were between 3.12 and 50 mg/mL. Conclusion: Based on the findings of this study, the aqueous extract of Morus nigra has shown strong bactericidal properties against all studied bacterial strains, which indicates its potential for therapeutic application.