Asadollah Mohammadi | University of Guilan (original) (raw)

Papers by Asadollah Mohammadi

Research paper thumbnail of Enhanced Photocatalytic Performance of TiO2 by β-Cyclodextrin for the Degradation of Organic Dyes

In this work, an efficient photocatalyst based on β-cyclodextrin-glycine-modified TiO2 nanopartic... more In this work, an efficient photocatalyst based on β-cyclodextrin-glycine-modified TiO2 nanoparticles (TiO2-Gly-βCD NPs) was successfully synthesized. The photocatalytic activity of the prepared TiO2-Gly-βCD was tested on the degradation of methylene blue (MB) and methyl orange (MO) dyes. The enhanced surface properties of TiO2-Gly-βCD photocatalyst generated excellent photocatalytic performance for the photocatalytic degradation of dyes in aqueous solution. These were strongly attributed to the presence of the functional hydroxyl groups and the inner cores of the hydrophobic cavity in β-CD to form inclusion complexes with organic molecules. As compared to the pure TiO2 and TiO2 modified by Gly, the dye degradation rate under UV irradiation was considerably enhanced by TiO2/Gly/βCD as a photocatalyst. In addition, the sonocatalytic degradation of dyes was investigated, and it was found that the ultrasonic waves slightly enhanced the degradation time of dyes. The results indicated tha...

Research paper thumbnail of Dyeing Properties of Some New Disperse Dyes Containing Piperazine Moiety

our novel azo disperse dyes based on 1-(4-bromobenzyl)-4phenylpiperazine were synthesized in two ... more our novel azo disperse dyes based on 1-(4-bromobenzyl)-4phenylpiperazine were synthesized in two steps, using alkylation and azo coupling reactions. Chemical structure of the dyes was characterized and confirmed by the Ultraviolet Visible, Fourrier Transform Infrared, Proton Nuclear Magnetic Resonance and Carbon Nuclear Magnetic Resonance analyses. The solvatochromic behavior of the dyes was studied in a set of 10 solvents with different polarity and considerable results were obtained. The prepared dyes were applied as disperse dyes for dyeing polyester fibers and their dyeing properties were evaluated. The fastness properties of the dyed fabrics such as wash, light and rubbing fastness degrees were measured by standard methods. Investigation of antioxidant activity of compounds was carried out by ferric reducing antioxidant power (FRAP) method. The activity data show that the synthesized dyes B1-B4 have promising antioxidant activity.

Research paper thumbnail of Naphthalene-based azo dyes: Synthesis, characterization and dyeing performance on polyester fibers

n the present study, five naphthalene-based azo dyes were obtained using classical azo coupling r... more n the present study, five naphthalene-based azo dyes were obtained using classical azo coupling reactions. The structure of the dyes was characterized and confirmed by the UV-Vis, FT-IR, 1 H NMR and 13 C NMR analyzes. The solvatochromic behavior of the dyes was studied in a set of 10 solvents with different polarity and considerable results were obtained. The dyes were applied as disperse dyes to polyester fiber and their dyeing properties were evaluated. The fastness properties of the dyed fabrics such as wash, light and rubbing fastness degrees were measured by standard methods. Additionally, the prepared dyes were evaluated for antioxidant activity by ferric reducing antioxidant power method.

Research paper thumbnail of Methylene Blue Removal Using Surface-Modified TiO2 Nanoparticles: A Comparative Study on Adsorption and Photocatalytic Degradation

This study describes the adsorption and photocatalytic removal of methylene blue (MB) from aqueo... more This study describes the adsorption and photocatalytic removal of methylene blue (MB) from aqueous solution by surface-modified TiO2 nanoparticles under ultraviolet irradiation in a batch system. The 5-sulfosalicylic acid grafted TiO2 (5-SA-TiO2) as a photocatalyst was characterized by means of XRD, FTIR and SEM techniques. The surface of TiO2 nanoparticles was modified by 5-sulfosalicylic acid (5-SA) to increase performance by altering surface properties. Notably, in contrast with the adsorption process, the remarkable removal enhancement of MB dye was observed by photocatalytic degradation process from aqueous solution. The adsorption and photocatalytic degradation kinetics of MB using 5-SA-TiO2 nanoparticles have also been investigated. The results show that the photocatalytic degradation was good fit with the pseudo-first-order kinetic model (R2 > 0.99). The adsorption isotherm of MB onto modified TiO2 nanoparticles fitted into the Temkin equation. In addition, thermodyn...

Research paper thumbnail of Synthesis and effective dispersion of Fe3O4 NPs on alfalfa as a green nanoadsorbent for the removal of cationic dyes from aqueous solutions

Research paper thumbnail of A new and efficient diaminopyrimidine-based colorimetric and fluorescence chemosensor for the highly selective and sensitive detection of Cu2+ in aqueous media and living cells

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy

Research paper thumbnail of A novel sulfamethoxazole derivative as an inhibitory agent against HSP70: A combination of computational with in vitro studies

International Journal of Biological Macromolecules

In the current study, a novel derivative of sulfamethoxazole (a sulfonamide containing anti-bioti... more In the current study, a novel derivative of sulfamethoxazole (a sulfonamide containing anti-biotic) named ZM-093 (IUPAC name: (E)-4-((4-(bis(2-hydroxyethyl)amino)phenyl)diazenyl)-N-(5-methylisoxazole-3-yl)benzenesulfonamide) was synthesized via common diazotization-coupling reactions from sulfamethoxazole and subsequently characterized through NMR/FT-IR spectroscopy. After evaluation, the compound was geometrically optimized at the DFT level of theory with BL3YP method and 6/31++G (d,p) basis set and from the optimized structure, several molecular descriptors important in the biological reactivity of the compound, such as global reactivity parameters, molecular electrostatic potential, average local ionization energy, and drug-likeness features of the compound were computationally analyzed. The experimental in vitro investigations of the interaction between ZM-093 and heat shock protein 70 (HSP70), a protein that is highly expressed in several types of cancers, exhibited a significant inhibitory effect against the chaperone activity of HSP70 for the titled compound (P-value < 0.01) and the comparison between the experimental studies with the mentioned computational analysis, as well as molecular docking, illustrated that ZM-093 may inhibit HSP70 through binding to its substrate-binding domain. Finally, by taking all the previous results into account, a new method for assessing the inhibitory activity of ligand to HSP70 is introduced based on protonography, a recently developed method that is dependent on the catalytic activity of carbonic anhydrase on polyacrylamide gel electrophoresis.

Research paper thumbnail of Sensitive and selective colorimetric detection of Cu (II) in water samples by thiazolylazopyrimidine-functionalized TiO2 nanoparticles

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy

Research paper thumbnail of Synthesis and comparison of two chromone based Schiff bases containing methoxy and acetamido substitutes as highly sustainable corrosion inhibitors for steel in hydrochloric acid

Journal of Molecular Structure

Research paper thumbnail of Synthesis and application of a new chemosensor based on the thiazolylazo-quinazolinone hybrid for detection of F− and S2− in aqueous solutions

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy

Research paper thumbnail of Epoxy-Triazinetrione-Functionalized Magnetic Nanoparticles as an Efficient Magnetic Nanoadsorbent for the Removal of Malachite Green and Pb(II) from Aqueous Solutions

Journal of Chemical & Engineering Data

In this study, a new epoxy-triazinetrione (ETT)-functionalized magnetic nanoadsorbent (Fe3O4-ETT)... more In this study, a new epoxy-triazinetrione (ETT)-functionalized magnetic nanoadsorbent (Fe3O4-ETT) has been developed for the removal of malachite green (MG) and Pb(II) from aqueous solutions. Fe3O4...

Research paper thumbnail of A simple and sensitive thiazole-based colorimetric chemosensor for detection of CN−, AcO− and Cu2+ ions

Journal of the Iranian Chemical Society

A thiazole-based chemosensor (TCS) for detection of important ions was synthesized in high yield ... more A thiazole-based chemosensor (TCS) for detection of important ions was synthesized in high yield through diazotization–coupling reactions. Sensor TCS in aqueous solution of acetonitrile displays notable colorimetric changes after addition of CN−, AcO− and Cu2+. On the basis of titration experiment and resultant good linear relationship between its absorbance and ions concentration, the LOD of TCS for CN−, AcO− and Cu2+ sensing were found to be of micro-molar (μM) level, respectively. Job’s plots revealed that the TCS interacts with corresponding ions using a 1:1 binding stoichiometry. Furthermore, the test papers of the TCS were successfully prepared and applied to detect related ions in aqueous solution. This shows the potential application of the developed sensor for the detection of ions in the chemical and biological samples without any spectroscopic instrumentation. Importantly, sensor TCS was used to retrieve CN− in real water samples with the least relative error.

Research paper thumbnail of Eco-friendly synthesis of maleate ester: A comparison between solid acid and enzyme-catalyzed esterification

Sustainable Chemistry and Pharmacy

Abstract In this study, two different eco-friendly methods were investigated for the synthesis of... more Abstract In this study, two different eco-friendly methods were investigated for the synthesis of a dicarboxylic acid ester, dimethyl maleate (DMM). One method involves application of molybdate sulfuric acid (MSA) as a solid acid catalyst in the esterification of maleic acid with methanol. The effects of three parameters namely, temperature, time, and catalyst amount on the product synthesis were determined. By using response surface methodology (RSM) based on central composite rotatable design (CCRD), maximum conversion of the maleic acid (87.6%) was obtained at reaction conditions of 120 °C, 0.27 g MSA, and 103 min. In the other method, DMM was synthesized by enzymatic esterification using immobilized Candida antarctica lipase B as the catalyst. Maximum conversion was 72.3%, at the optimal conditions of 62.5 °C, 0.27 g enzyme, and 249 min. The reusability study showed that MSA lost its catalytic activity after five cycles. However, the immobilized enzyme maintained its activity and stability. The results indicated that both employed methods were efficient for the synthesis of DMM. A higher conversion could be obtained using MSA as the catalyst, which could be compensated by better reusability of the enzyme. The enzyme-catalyzed reaction was more energy efficient but it took a longer time to obtain maximum reaction yield.

Research paper thumbnail of A novel uracil-based chemosensor for sequential detection of copper (II) and cyanide ions and its application in real samples

Journal of Photochemistry and Photobiology A: Chemistry

Abstract A simple uracil based chemosensor (UraCS) has been developed for sequential detection of... more Abstract A simple uracil based chemosensor (UraCS) has been developed for sequential detection of Cu2+ and CN− in aqueous acetonitrile solution. The sensor UraCS showed a high selectivity, high sensitivity and quick response to copper ions in the presence of other competing cations including Cd2+, Fe2+, Hg2+, Al3+, Ni2+, Ba2+, Ca2+, Cr3+, Co2+, Zn2+, Cu2+, Pb2+, Ag+, Fe3+ and K+. In the presence of Cu2+, UraCS provided a distinct color change from colorless to dark yellow forming a complex with a 2:1 stoichiometry and reverse color change after addition of CN‾ to the probe containing UraCS-Cu2+ complex. More importantly, the results confirmed that the UraCS has widely linear detection range of 3.0 to 150 µM toward Cu2+ ions. The calculated limit of detection for Cu2+ ions was low as 0.28 μM. Moreover, interaction of UraCS with Cu2+ causes a significant fluorescence quenching at 378 nm. UraCS-Cu2+ complex could be successfully applied to detect cyanide ions via Cu2+ displacement approach. The free UraCS was recovered after adding the CN‾ ions in a few seconds due to the formation of the stable copper cyanide complex Cu(CN)x. The DFT calculation was also performed for better understanding of the Cu2+ sensing mechanism. Furthermore, chemosensor UraCS was successfully utilized in the preparation of test strips and supported silica gel for the detection of Cu2+ and CN− ions from aqueous environment and real water samples.

Research paper thumbnail of A simple pyrimidine based chemosensor for sequential detection of copper (II) and cyanide ions and its application in real samples

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy

In this study, a new pyrimidine-based chemosensor (PyrCS) has been developed for sequential detec... more In this study, a new pyrimidine-based chemosensor (PyrCS) has been developed for sequential detection of copper (II) and cyanide ions. The PyrCS has revealed high sensitivity and selectivity toward copper ion over other metal ions in aqueous media. The PyrCS as an optical probe exhibited a distinct color change and a bathochromic shift in UV spectra in the presence of copper ion in a few seconds due to the formation of stable complex (PyrCS-Cu2+). The results confirmed that the PyrCS has a widely linear detection range of 0.3-30 μM toward Cu2+. The calculated limit of detection for Cu2+ ions was low as 0.116 μM. Moreover, the fluorescent intensity of PyrCS at 507 nm was significantly quenched in the presence of Cu2⁺ and Fe2⁺ ions. Additionally, complex PyrCS-Cu2+ was successfully used to detect cyanide ions via Cu2+ displacement approach. The free PyrCS was recovered after adding the CN‾ ions in a few seconds due to the formation of the stable copper cyanide complex Cu(CN)x. The calculated LOD for CN‾ ions was low as 0.320 μM. The data also clarified that the other competing anions did not create a clear color change in solutions. Since the proposed method could provide a vivid colorimetric response in the presence of detected analytes within the pH range of 3-9, we can claim that the developed chemosensor can be utilized in any physical and biological conditions.

Research paper thumbnail of Rapid, sensitive and selective detection of arginine using a simple azo-based colorimetric and fluorescent chemosensor

Journal of Photochemistry and Photobiology A: Chemistry

Abstract In this work, a new thiazole-based colorimetric and fluorescent chemosensor (ThiCS) has ... more Abstract In this work, a new thiazole-based colorimetric and fluorescent chemosensor (ThiCS) has been developed for arginine (Arg) detection. It has revealed high sensitivity and selectivity toward arginine over other amino acids in aqueous acetonitrile media. Among various amino acids, only the amino acid arginine exhibited a visual color change and a bathochromic shift in UV–vis spectra in a few seconds due to the charge transformation between azo group of sensor and guanidino group of Arg. Moreover, interaction of ThiCS with Arg cause a red-shift in fluorescence emission accompanied with the fluorescence enhancement at 545 nm and fluorescence quenching at 486 nm. Since ThiCS could provide a vivid and reasonable response in the presence of detected amino acid within the pH range of 5–9, we can claim that the chemosensor can be utilized in any physical and biological conditions. More importantly, the sensor ThiCS has a wide linear detection range, low detection limit, high selectivity, and rapid response time for the detection of arginine under the experimental conditions. Besides, Arg can be detected in human blood plasma through this method resulting satisfactory color and spectral changes, which demonstrates the potential of application of ThiCS in real analysis.

Research paper thumbnail of A novel chromone based colorimetric sensor for highly selective detection of copper ions: Synthesis, optical properties and DFT calculations

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy

In this work, a new chromone based colorimetric sensor (ChrCS) was developed for highly selective... more In this work, a new chromone based colorimetric sensor (ChrCS) was developed for highly selective detection of copper ions in semi-aqueous media. Evaluation of color and spectral changes displayed by the developed sensor shows that the sensor can be applied to detect copper ions in the presence of other competing metal ions and anions. The developed sensor, which contains biologically active chromone ring, shows excellent selectivity at microlevel for Cu2+ with a color change from colorless to yellow. Job's plot based on spectroscopic data showed the complex formation between ChrCS and Cu2+ ions has the stoichiometric ratio of 1:1 (ChrCS-Cu2+ complex). In addition, the binding constant of the ChrCS to Cu2+ was determined using the Benesi-Hildebrand equation. Furthermore, the test papers of the developed ChrCS were successfully prepared and employed to detect different concentration Cu2+ (10-3 M to 10-7 M) in aqueous solution. Importantly, sensor ChrCS was applied to detect Cu2+ ions in real water samples. To better understand the optical character of ChrCS and the effect of metal ion titration, density functional theory (DFT) calculations at the B3LYP/6-31 + G(d,p) level were performed for ChrCS and its complex ChrCS-Cu2+. Furthermore, on the basis of the Job's plot analysis DFT calculations, and reversible nature of the developed sensor, the sensing mechanism was demonstrated.

Research paper thumbnail of Chemical sensor using metal-organic complex: Preparation, characterization and application for highly selective detection of cyanide ions in mixed aqueous-organic media

Journal of Photochemistry and Photobiology A: Chemistry

Abstract In this study, a novel metal-organic hybrid material (MO1) was designed and synthesized ... more Abstract In this study, a novel metal-organic hybrid material (MO1) was designed and synthesized for the detection of CN− ions. The spectral analyses by FT-IR, 1H NMR, 13C NMR, CHN and TGA satisfactorily confirmed the structure of MO1. The sensor MO1 was applied as colorimetric probe for sensing of cyanide ions in aqueous solutions of dimethyl sulfoxide. MO1 with electron withdrawing group at organic ligand showed high selectivity for detection of cyanide over other interfering anions. Interaction of MO1 with cyanide provides obvious colorimetric change from red to violet, enabling easy detect with the naked eye. In addition, the sensing details were evaluated using UV–vis spectroscopy. Furthermore, the detection limit of chemosensor toward CN‾ ions was found to be 5.52 μM. Moreover, probe MO1 can be used for selective sensing of cyanide based on the obvious color changes in real samples.

Research paper thumbnail of A simple colorimetric chemosensor with highly performance for detection of cyanide and copper ions and its practical application in real samples

Journal of Photochemistry and Photobiology A: Chemistry

Abstract Two novel and simple azo-based compounds with electron-withdrawing and electron-donating... more Abstract Two novel and simple azo-based compounds with electron-withdrawing and electron-donating groups (M1 and M2) were synthesized by the diazotization procedure. The synthesized compounds were then applied for detection of important ions in aqueous solutions of acetonitrile. Sensor M1 with electron-withdrawing group (EWG) showed distinct colorimetric responses towards CNˉ (light yellow to red) and Cu2+ (light yellow to dark yellow). Through titration experiment, the detection limit (LOD) of M1 for CNˉ and Cu2+ ions sensing were found to be nano molar (nM) level. Job’s plot based on spectroscopic data showed the complexes formation between M1 and ions has the stoichiometric ratio of 1:1 (M1-CNˉ and M1-Cu2+). In addition, the binding constants for M1 towards CNˉ and Cu2+ were determined using the Benesi-Hildebrand equation. Furthermore, the M1-based test papers strips were successfully used to the rapid detection of CNˉ ions in semi‐aqueous medium. Importantly, sensor M1 was applied to detect CNˉ and Cu2+ in real water samples and apple seeds samples. However, for M2, containing electron-donating group (EDG), no clear color changes were observed in the presence of investigated ions.

Research paper thumbnail of A cyclodextrin/glycine-functionalized TiO 2 nanoadsorbent: Synthesis, characterization and application for the removal of organic pollutants from water and real textile wastewater

Process Safety and Environmental Protection

Abstract In this paper, β-cyclodextrin-glycine-modified TiO2 nanoparticles (TiO2/Gly/β-CD NPs) as... more Abstract In this paper, β-cyclodextrin-glycine-modified TiO2 nanoparticles (TiO2/Gly/β-CD NPs) as a nano-adsorbent were prepared and employed for the removal of some organic pollutants from aqueous solutions. Results from FT-IR, FESEM, TEM, XRD, EDX and BET surface area measurement showed that the TiO2 NPs was modified with Gly and βeta-cyclodextrin (β-CD). The effect of environmental factors, including pH, contact time, adsorbent dosage, temperature, and initial dye concentration on the adsorption ability of the TiO2/Gly/β-CD were investigated in detail. The results of this study showed that TiO2/Gly/β-CD has high adsorption efficiency toward organic dyes, and were comparable with other adsorbents. The adsorption capacities of MB, MO, AB113, and DR1 onto TiO2/Gly/β-CD NPs are found to be 81.97 mg/g, 384.62 mg/g, 76.92 mg/g, and 138.89 mg/g, respectively. In addition, the adsorbent presented can be used in several adsorption–desorption cycles. The dye adsorption kinetics, thermodynamics and isotherms were also investigated. The results indicated that pseudo-second-order kinetic model with correlation coefficients greater than 0.9971, and Freundlich isotherm model with correlation coefficients greater than 0.991 well describe the adsorption of MB, MO, AB113, and DR1 on the TiO2/Gly/β-CD NPs. Moreover, the thermodynamic parameters indicated that the adsorption process for all types of organic dyes was exothermic. Additionally, the adsorbent was successfully applied to remove industrial dyes from real textile wastewater with satisfactory results.

Research paper thumbnail of Enhanced Photocatalytic Performance of TiO2 by β-Cyclodextrin for the Degradation of Organic Dyes

In this work, an efficient photocatalyst based on β-cyclodextrin-glycine-modified TiO2 nanopartic... more In this work, an efficient photocatalyst based on β-cyclodextrin-glycine-modified TiO2 nanoparticles (TiO2-Gly-βCD NPs) was successfully synthesized. The photocatalytic activity of the prepared TiO2-Gly-βCD was tested on the degradation of methylene blue (MB) and methyl orange (MO) dyes. The enhanced surface properties of TiO2-Gly-βCD photocatalyst generated excellent photocatalytic performance for the photocatalytic degradation of dyes in aqueous solution. These were strongly attributed to the presence of the functional hydroxyl groups and the inner cores of the hydrophobic cavity in β-CD to form inclusion complexes with organic molecules. As compared to the pure TiO2 and TiO2 modified by Gly, the dye degradation rate under UV irradiation was considerably enhanced by TiO2/Gly/βCD as a photocatalyst. In addition, the sonocatalytic degradation of dyes was investigated, and it was found that the ultrasonic waves slightly enhanced the degradation time of dyes. The results indicated tha...

Research paper thumbnail of Dyeing Properties of Some New Disperse Dyes Containing Piperazine Moiety

our novel azo disperse dyes based on 1-(4-bromobenzyl)-4phenylpiperazine were synthesized in two ... more our novel azo disperse dyes based on 1-(4-bromobenzyl)-4phenylpiperazine were synthesized in two steps, using alkylation and azo coupling reactions. Chemical structure of the dyes was characterized and confirmed by the Ultraviolet Visible, Fourrier Transform Infrared, Proton Nuclear Magnetic Resonance and Carbon Nuclear Magnetic Resonance analyses. The solvatochromic behavior of the dyes was studied in a set of 10 solvents with different polarity and considerable results were obtained. The prepared dyes were applied as disperse dyes for dyeing polyester fibers and their dyeing properties were evaluated. The fastness properties of the dyed fabrics such as wash, light and rubbing fastness degrees were measured by standard methods. Investigation of antioxidant activity of compounds was carried out by ferric reducing antioxidant power (FRAP) method. The activity data show that the synthesized dyes B1-B4 have promising antioxidant activity.

Research paper thumbnail of Naphthalene-based azo dyes: Synthesis, characterization and dyeing performance on polyester fibers

n the present study, five naphthalene-based azo dyes were obtained using classical azo coupling r... more n the present study, five naphthalene-based azo dyes were obtained using classical azo coupling reactions. The structure of the dyes was characterized and confirmed by the UV-Vis, FT-IR, 1 H NMR and 13 C NMR analyzes. The solvatochromic behavior of the dyes was studied in a set of 10 solvents with different polarity and considerable results were obtained. The dyes were applied as disperse dyes to polyester fiber and their dyeing properties were evaluated. The fastness properties of the dyed fabrics such as wash, light and rubbing fastness degrees were measured by standard methods. Additionally, the prepared dyes were evaluated for antioxidant activity by ferric reducing antioxidant power method.

Research paper thumbnail of Methylene Blue Removal Using Surface-Modified TiO2 Nanoparticles: A Comparative Study on Adsorption and Photocatalytic Degradation

This study describes the adsorption and photocatalytic removal of methylene blue (MB) from aqueo... more This study describes the adsorption and photocatalytic removal of methylene blue (MB) from aqueous solution by surface-modified TiO2 nanoparticles under ultraviolet irradiation in a batch system. The 5-sulfosalicylic acid grafted TiO2 (5-SA-TiO2) as a photocatalyst was characterized by means of XRD, FTIR and SEM techniques. The surface of TiO2 nanoparticles was modified by 5-sulfosalicylic acid (5-SA) to increase performance by altering surface properties. Notably, in contrast with the adsorption process, the remarkable removal enhancement of MB dye was observed by photocatalytic degradation process from aqueous solution. The adsorption and photocatalytic degradation kinetics of MB using 5-SA-TiO2 nanoparticles have also been investigated. The results show that the photocatalytic degradation was good fit with the pseudo-first-order kinetic model (R2 > 0.99). The adsorption isotherm of MB onto modified TiO2 nanoparticles fitted into the Temkin equation. In addition, thermodyn...

Research paper thumbnail of Synthesis and effective dispersion of Fe3O4 NPs on alfalfa as a green nanoadsorbent for the removal of cationic dyes from aqueous solutions

Research paper thumbnail of A new and efficient diaminopyrimidine-based colorimetric and fluorescence chemosensor for the highly selective and sensitive detection of Cu2+ in aqueous media and living cells

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy

Research paper thumbnail of A novel sulfamethoxazole derivative as an inhibitory agent against HSP70: A combination of computational with in vitro studies

International Journal of Biological Macromolecules

In the current study, a novel derivative of sulfamethoxazole (a sulfonamide containing anti-bioti... more In the current study, a novel derivative of sulfamethoxazole (a sulfonamide containing anti-biotic) named ZM-093 (IUPAC name: (E)-4-((4-(bis(2-hydroxyethyl)amino)phenyl)diazenyl)-N-(5-methylisoxazole-3-yl)benzenesulfonamide) was synthesized via common diazotization-coupling reactions from sulfamethoxazole and subsequently characterized through NMR/FT-IR spectroscopy. After evaluation, the compound was geometrically optimized at the DFT level of theory with BL3YP method and 6/31++G (d,p) basis set and from the optimized structure, several molecular descriptors important in the biological reactivity of the compound, such as global reactivity parameters, molecular electrostatic potential, average local ionization energy, and drug-likeness features of the compound were computationally analyzed. The experimental in vitro investigations of the interaction between ZM-093 and heat shock protein 70 (HSP70), a protein that is highly expressed in several types of cancers, exhibited a significant inhibitory effect against the chaperone activity of HSP70 for the titled compound (P-value < 0.01) and the comparison between the experimental studies with the mentioned computational analysis, as well as molecular docking, illustrated that ZM-093 may inhibit HSP70 through binding to its substrate-binding domain. Finally, by taking all the previous results into account, a new method for assessing the inhibitory activity of ligand to HSP70 is introduced based on protonography, a recently developed method that is dependent on the catalytic activity of carbonic anhydrase on polyacrylamide gel electrophoresis.

Research paper thumbnail of Sensitive and selective colorimetric detection of Cu (II) in water samples by thiazolylazopyrimidine-functionalized TiO2 nanoparticles

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy

Research paper thumbnail of Synthesis and comparison of two chromone based Schiff bases containing methoxy and acetamido substitutes as highly sustainable corrosion inhibitors for steel in hydrochloric acid

Journal of Molecular Structure

Research paper thumbnail of Synthesis and application of a new chemosensor based on the thiazolylazo-quinazolinone hybrid for detection of F− and S2− in aqueous solutions

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy

Research paper thumbnail of Epoxy-Triazinetrione-Functionalized Magnetic Nanoparticles as an Efficient Magnetic Nanoadsorbent for the Removal of Malachite Green and Pb(II) from Aqueous Solutions

Journal of Chemical & Engineering Data

In this study, a new epoxy-triazinetrione (ETT)-functionalized magnetic nanoadsorbent (Fe3O4-ETT)... more In this study, a new epoxy-triazinetrione (ETT)-functionalized magnetic nanoadsorbent (Fe3O4-ETT) has been developed for the removal of malachite green (MG) and Pb(II) from aqueous solutions. Fe3O4...

Research paper thumbnail of A simple and sensitive thiazole-based colorimetric chemosensor for detection of CN−, AcO− and Cu2+ ions

Journal of the Iranian Chemical Society

A thiazole-based chemosensor (TCS) for detection of important ions was synthesized in high yield ... more A thiazole-based chemosensor (TCS) for detection of important ions was synthesized in high yield through diazotization–coupling reactions. Sensor TCS in aqueous solution of acetonitrile displays notable colorimetric changes after addition of CN−, AcO− and Cu2+. On the basis of titration experiment and resultant good linear relationship between its absorbance and ions concentration, the LOD of TCS for CN−, AcO− and Cu2+ sensing were found to be of micro-molar (μM) level, respectively. Job’s plots revealed that the TCS interacts with corresponding ions using a 1:1 binding stoichiometry. Furthermore, the test papers of the TCS were successfully prepared and applied to detect related ions in aqueous solution. This shows the potential application of the developed sensor for the detection of ions in the chemical and biological samples without any spectroscopic instrumentation. Importantly, sensor TCS was used to retrieve CN− in real water samples with the least relative error.

Research paper thumbnail of Eco-friendly synthesis of maleate ester: A comparison between solid acid and enzyme-catalyzed esterification

Sustainable Chemistry and Pharmacy

Abstract In this study, two different eco-friendly methods were investigated for the synthesis of... more Abstract In this study, two different eco-friendly methods were investigated for the synthesis of a dicarboxylic acid ester, dimethyl maleate (DMM). One method involves application of molybdate sulfuric acid (MSA) as a solid acid catalyst in the esterification of maleic acid with methanol. The effects of three parameters namely, temperature, time, and catalyst amount on the product synthesis were determined. By using response surface methodology (RSM) based on central composite rotatable design (CCRD), maximum conversion of the maleic acid (87.6%) was obtained at reaction conditions of 120 °C, 0.27 g MSA, and 103 min. In the other method, DMM was synthesized by enzymatic esterification using immobilized Candida antarctica lipase B as the catalyst. Maximum conversion was 72.3%, at the optimal conditions of 62.5 °C, 0.27 g enzyme, and 249 min. The reusability study showed that MSA lost its catalytic activity after five cycles. However, the immobilized enzyme maintained its activity and stability. The results indicated that both employed methods were efficient for the synthesis of DMM. A higher conversion could be obtained using MSA as the catalyst, which could be compensated by better reusability of the enzyme. The enzyme-catalyzed reaction was more energy efficient but it took a longer time to obtain maximum reaction yield.

Research paper thumbnail of A novel uracil-based chemosensor for sequential detection of copper (II) and cyanide ions and its application in real samples

Journal of Photochemistry and Photobiology A: Chemistry

Abstract A simple uracil based chemosensor (UraCS) has been developed for sequential detection of... more Abstract A simple uracil based chemosensor (UraCS) has been developed for sequential detection of Cu2+ and CN− in aqueous acetonitrile solution. The sensor UraCS showed a high selectivity, high sensitivity and quick response to copper ions in the presence of other competing cations including Cd2+, Fe2+, Hg2+, Al3+, Ni2+, Ba2+, Ca2+, Cr3+, Co2+, Zn2+, Cu2+, Pb2+, Ag+, Fe3+ and K+. In the presence of Cu2+, UraCS provided a distinct color change from colorless to dark yellow forming a complex with a 2:1 stoichiometry and reverse color change after addition of CN‾ to the probe containing UraCS-Cu2+ complex. More importantly, the results confirmed that the UraCS has widely linear detection range of 3.0 to 150 µM toward Cu2+ ions. The calculated limit of detection for Cu2+ ions was low as 0.28 μM. Moreover, interaction of UraCS with Cu2+ causes a significant fluorescence quenching at 378 nm. UraCS-Cu2+ complex could be successfully applied to detect cyanide ions via Cu2+ displacement approach. The free UraCS was recovered after adding the CN‾ ions in a few seconds due to the formation of the stable copper cyanide complex Cu(CN)x. The DFT calculation was also performed for better understanding of the Cu2+ sensing mechanism. Furthermore, chemosensor UraCS was successfully utilized in the preparation of test strips and supported silica gel for the detection of Cu2+ and CN− ions from aqueous environment and real water samples.

Research paper thumbnail of A simple pyrimidine based chemosensor for sequential detection of copper (II) and cyanide ions and its application in real samples

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy

In this study, a new pyrimidine-based chemosensor (PyrCS) has been developed for sequential detec... more In this study, a new pyrimidine-based chemosensor (PyrCS) has been developed for sequential detection of copper (II) and cyanide ions. The PyrCS has revealed high sensitivity and selectivity toward copper ion over other metal ions in aqueous media. The PyrCS as an optical probe exhibited a distinct color change and a bathochromic shift in UV spectra in the presence of copper ion in a few seconds due to the formation of stable complex (PyrCS-Cu2+). The results confirmed that the PyrCS has a widely linear detection range of 0.3-30 μM toward Cu2+. The calculated limit of detection for Cu2+ ions was low as 0.116 μM. Moreover, the fluorescent intensity of PyrCS at 507 nm was significantly quenched in the presence of Cu2⁺ and Fe2⁺ ions. Additionally, complex PyrCS-Cu2+ was successfully used to detect cyanide ions via Cu2+ displacement approach. The free PyrCS was recovered after adding the CN‾ ions in a few seconds due to the formation of the stable copper cyanide complex Cu(CN)x. The calculated LOD for CN‾ ions was low as 0.320 μM. The data also clarified that the other competing anions did not create a clear color change in solutions. Since the proposed method could provide a vivid colorimetric response in the presence of detected analytes within the pH range of 3-9, we can claim that the developed chemosensor can be utilized in any physical and biological conditions.

Research paper thumbnail of Rapid, sensitive and selective detection of arginine using a simple azo-based colorimetric and fluorescent chemosensor

Journal of Photochemistry and Photobiology A: Chemistry

Abstract In this work, a new thiazole-based colorimetric and fluorescent chemosensor (ThiCS) has ... more Abstract In this work, a new thiazole-based colorimetric and fluorescent chemosensor (ThiCS) has been developed for arginine (Arg) detection. It has revealed high sensitivity and selectivity toward arginine over other amino acids in aqueous acetonitrile media. Among various amino acids, only the amino acid arginine exhibited a visual color change and a bathochromic shift in UV–vis spectra in a few seconds due to the charge transformation between azo group of sensor and guanidino group of Arg. Moreover, interaction of ThiCS with Arg cause a red-shift in fluorescence emission accompanied with the fluorescence enhancement at 545 nm and fluorescence quenching at 486 nm. Since ThiCS could provide a vivid and reasonable response in the presence of detected amino acid within the pH range of 5–9, we can claim that the chemosensor can be utilized in any physical and biological conditions. More importantly, the sensor ThiCS has a wide linear detection range, low detection limit, high selectivity, and rapid response time for the detection of arginine under the experimental conditions. Besides, Arg can be detected in human blood plasma through this method resulting satisfactory color and spectral changes, which demonstrates the potential of application of ThiCS in real analysis.

Research paper thumbnail of A novel chromone based colorimetric sensor for highly selective detection of copper ions: Synthesis, optical properties and DFT calculations

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy

In this work, a new chromone based colorimetric sensor (ChrCS) was developed for highly selective... more In this work, a new chromone based colorimetric sensor (ChrCS) was developed for highly selective detection of copper ions in semi-aqueous media. Evaluation of color and spectral changes displayed by the developed sensor shows that the sensor can be applied to detect copper ions in the presence of other competing metal ions and anions. The developed sensor, which contains biologically active chromone ring, shows excellent selectivity at microlevel for Cu2+ with a color change from colorless to yellow. Job's plot based on spectroscopic data showed the complex formation between ChrCS and Cu2+ ions has the stoichiometric ratio of 1:1 (ChrCS-Cu2+ complex). In addition, the binding constant of the ChrCS to Cu2+ was determined using the Benesi-Hildebrand equation. Furthermore, the test papers of the developed ChrCS were successfully prepared and employed to detect different concentration Cu2+ (10-3 M to 10-7 M) in aqueous solution. Importantly, sensor ChrCS was applied to detect Cu2+ ions in real water samples. To better understand the optical character of ChrCS and the effect of metal ion titration, density functional theory (DFT) calculations at the B3LYP/6-31 + G(d,p) level were performed for ChrCS and its complex ChrCS-Cu2+. Furthermore, on the basis of the Job's plot analysis DFT calculations, and reversible nature of the developed sensor, the sensing mechanism was demonstrated.

Research paper thumbnail of Chemical sensor using metal-organic complex: Preparation, characterization and application for highly selective detection of cyanide ions in mixed aqueous-organic media

Journal of Photochemistry and Photobiology A: Chemistry

Abstract In this study, a novel metal-organic hybrid material (MO1) was designed and synthesized ... more Abstract In this study, a novel metal-organic hybrid material (MO1) was designed and synthesized for the detection of CN− ions. The spectral analyses by FT-IR, 1H NMR, 13C NMR, CHN and TGA satisfactorily confirmed the structure of MO1. The sensor MO1 was applied as colorimetric probe for sensing of cyanide ions in aqueous solutions of dimethyl sulfoxide. MO1 with electron withdrawing group at organic ligand showed high selectivity for detection of cyanide over other interfering anions. Interaction of MO1 with cyanide provides obvious colorimetric change from red to violet, enabling easy detect with the naked eye. In addition, the sensing details were evaluated using UV–vis spectroscopy. Furthermore, the detection limit of chemosensor toward CN‾ ions was found to be 5.52 μM. Moreover, probe MO1 can be used for selective sensing of cyanide based on the obvious color changes in real samples.

Research paper thumbnail of A simple colorimetric chemosensor with highly performance for detection of cyanide and copper ions and its practical application in real samples

Journal of Photochemistry and Photobiology A: Chemistry

Abstract Two novel and simple azo-based compounds with electron-withdrawing and electron-donating... more Abstract Two novel and simple azo-based compounds with electron-withdrawing and electron-donating groups (M1 and M2) were synthesized by the diazotization procedure. The synthesized compounds were then applied for detection of important ions in aqueous solutions of acetonitrile. Sensor M1 with electron-withdrawing group (EWG) showed distinct colorimetric responses towards CNˉ (light yellow to red) and Cu2+ (light yellow to dark yellow). Through titration experiment, the detection limit (LOD) of M1 for CNˉ and Cu2+ ions sensing were found to be nano molar (nM) level. Job’s plot based on spectroscopic data showed the complexes formation between M1 and ions has the stoichiometric ratio of 1:1 (M1-CNˉ and M1-Cu2+). In addition, the binding constants for M1 towards CNˉ and Cu2+ were determined using the Benesi-Hildebrand equation. Furthermore, the M1-based test papers strips were successfully used to the rapid detection of CNˉ ions in semi‐aqueous medium. Importantly, sensor M1 was applied to detect CNˉ and Cu2+ in real water samples and apple seeds samples. However, for M2, containing electron-donating group (EDG), no clear color changes were observed in the presence of investigated ions.

Research paper thumbnail of A cyclodextrin/glycine-functionalized TiO 2 nanoadsorbent: Synthesis, characterization and application for the removal of organic pollutants from water and real textile wastewater

Process Safety and Environmental Protection

Abstract In this paper, β-cyclodextrin-glycine-modified TiO2 nanoparticles (TiO2/Gly/β-CD NPs) as... more Abstract In this paper, β-cyclodextrin-glycine-modified TiO2 nanoparticles (TiO2/Gly/β-CD NPs) as a nano-adsorbent were prepared and employed for the removal of some organic pollutants from aqueous solutions. Results from FT-IR, FESEM, TEM, XRD, EDX and BET surface area measurement showed that the TiO2 NPs was modified with Gly and βeta-cyclodextrin (β-CD). The effect of environmental factors, including pH, contact time, adsorbent dosage, temperature, and initial dye concentration on the adsorption ability of the TiO2/Gly/β-CD were investigated in detail. The results of this study showed that TiO2/Gly/β-CD has high adsorption efficiency toward organic dyes, and were comparable with other adsorbents. The adsorption capacities of MB, MO, AB113, and DR1 onto TiO2/Gly/β-CD NPs are found to be 81.97 mg/g, 384.62 mg/g, 76.92 mg/g, and 138.89 mg/g, respectively. In addition, the adsorbent presented can be used in several adsorption–desorption cycles. The dye adsorption kinetics, thermodynamics and isotherms were also investigated. The results indicated that pseudo-second-order kinetic model with correlation coefficients greater than 0.9971, and Freundlich isotherm model with correlation coefficients greater than 0.991 well describe the adsorption of MB, MO, AB113, and DR1 on the TiO2/Gly/β-CD NPs. Moreover, the thermodynamic parameters indicated that the adsorption process for all types of organic dyes was exothermic. Additionally, the adsorbent was successfully applied to remove industrial dyes from real textile wastewater with satisfactory results.