Meera Moydeen - Academia.edu (original) (raw)

Papers by Meera Moydeen

Research paper thumbnail of Synthesis, crystal structure, DFT calculations and antimicrobial activity of 4-(4-Fluoro-phenyl)-2,6-dimethyl-1,4-dihydro-pyridine-3,5-dicarboxylic acid diethyl ester

The title compound was synthesized and confirmed by FT-IR, H, C NMR analysis. The molecular struc... more The title compound was synthesized and confirmed by FT-IR, H, C NMR analysis. The molecular structure of the compound was precisely determined by Single Crystal X-ray Diffraction (SC-XRD) analysis. The crystalized compound shows P21/C & monoclinic crystal system with cell parameters a = 9.7768 (5), b = 7.4005(3) and c = 24.8099 (12), β=93.734(2)°.The structural and electronic properties of the compound were carried out by Density Functional Theory (DFT) calculations. The compound exhibited H-bonding between N1-H1A-----O1 with bond distance 2.98(7) A°).The energy gap Egap 4.53eV and Egap= 4.34eV for crystal and DFT method respectively. The molecular orbitals energies were studied through Highest Unoccupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) analysis. The softness and hardness of the molecule was studied through Global Chemical Reactivity Descriptors (GCRD). The electrophilic and nucleophilic characters were studied through Molecular Electrostatic ...

Research paper thumbnail of Fabrication, microstructure characterization and degradation performance of electrospun mats based on poly(3‐hydroxybutyrate‐ co ‐3 hydroxyvalerate)/polyethylene glycol blend for potential tissue engineering

Research paper thumbnail of Synthesis, crystal structure, quantum calculation and Hirshfeld surface analysis of 4-bromoanilinium oxalate hemihydrate single crystal

Journal of Molecular Structure

Research paper thumbnail of Recent Advantages of Biopolymer Preparation and Applications in Bio-Industry

Research paper thumbnail of Biocidal Polymers: Synthesis, Characterization and Antimicrobial Activity of Bis-Quaternary Onium Salts of Poly(aspartate-co-succinimide)

Polymers

Microbial multidrug resistance presents a real problem to human health. Therefore, water-soluble ... more Microbial multidrug resistance presents a real problem to human health. Therefore, water-soluble polymers based on poly(aspartate-co-succinimide) were synthesized via reaction of poly(aspartate-co-succinimide) with bis-quaternary ammonium or quaternary salts. The resultant copolymers were characterized by various techniques such as FTIR, TGA, 1HNMR, 13CNMR and elemental microanalysis. Antimicrobial activities of the new onium salts were investigated against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella typhi, and the fungi; Candida albicans,Aspergillus niger, Cryptococcus neoformans and Aspergillus flavus by agar diffusion method. Antimicrobial activity was studied in terms of inhibition zone diameters, in addition to the estimation of minimal inhibitory concentration (MIC) of the prepared compounds. A. niger and E. coli were the most affected microorganisms among the tested microorganisms with an inhibition zone of 19–21 (mm) in case of biocides, (...

Research paper thumbnail of Modified Electrospun Polymeric Nanofibers and Their Nanocomposites as Nanoadsorbents for Toxic Dye Removal from Contaminated Waters: A Review

Polymers

Electrospun polymer nanofibers (EPNFs) as one-dimensional nanostructures are characterized by a h... more Electrospun polymer nanofibers (EPNFs) as one-dimensional nanostructures are characterized by a high surface area-to-volume ratio, high porosity, large number of adsorption sites and high adsorption capacity. These properties nominate them to be used as an effective adsorbent for the removal of water pollutants such as heavy metals, dyes and other pollutants. Organic dyes are considered one of the most hazardous water pollutants due to their toxic effects even at very low concentrations. To overcome this problem, the adsorption technique has proven its high effectiveness towards the removal of such pollutants from aqueous systems. The use of the adsorption technique depends mainly on the properties, efficacy, cost and reusability of the adsorbent. So, the use of EPNFs as adsorbents for dye removal has received increasing attention due to their unique properties, adsorption efficiency and reusability. Moreover, the adsorption efficiency and stability of EPNFs in aqueous media can be ...

Research paper thumbnail of Synthesis of lanthanide‐doped strontium aluminate nanoparticles encapsulated in polyacrylonitrile nanofibers: Photoluminescence properties for anti‐counterfeiting applications

Luminescence

Photochromism has been applied as an interesting technique to improve the anti-counterfeiting of ... more Photochromism has been applied as an interesting technique to improve the anti-counterfeiting of commercial commodities. In order to build up a mechanically reliable anti-counterfeiting nanocomposite, it has been vital to enhance the engineering process of the anti-counterfeiting material. In the current study, we developed mechanically reliable and highly photoluminescent lanthanide-doped strontium aluminate nanoparticles (LSAN)/polyacrylonitrile (PAN) hybrid nanofibers successfully fabricated by electrospinning technique for anti-counterfeiting applications. The produced nanocomposite films exhibited ultraviolet-induced photochromic anti-counterfeiting property. In order to guarantee the transparent of the LSAN-PAN film, LSAN must be immobilized into the nanoparticle size to allow better dispersion without aggregation in the polyacrylonitrile matrix. The LSAN-PAN nanofibrous film demonstrated absorbance intensity at 354 nm associated with an emission intensity at 424 nm. The produced LSAN-PAN films demonstrated an enhanced hydrophobicity with increasing the ratio of LSAN without adversely influence their native appearance and mechanical performance. Upon excitation with ultraviolet, the translucent nanofibrous substrates exhibited fast and reversible photochromic activity to greenish-yellow without exhaustion. The nanofibrous films exhibited stretchability, transparency, flexibility and ultraviolet-induced photochromism at low-cost. The current strategy can be considered as an efficient technique toward the development of various anti-counterfeiting materials for a better market with economic and social values.

Research paper thumbnail of Enhancement the electrical conductivity of the synthesized polyvinylidene fluoride/polyvinyl chloride composite doped with palladium nanoparticles via laser ablation

Journal of Materials Research and Technology

Research paper thumbnail of In Situ Preparation of Novel Porous Nanocomposite Hydrogel as Effective Adsorbent for the Removal of Cationic Dyes from Polluted Water

Polymers

The use of some hydrogels as adsorbents for pollutants removal from wastewater is limited due to ... more The use of some hydrogels as adsorbents for pollutants removal from wastewater is limited due to their high swelling properties and the difficulty in recovering them after the adsorption process. To overcome these problems, a new hydrogel nanocomposite based on chitosan-grafted-polyacrylic acid/oxidized electrospun carbon nanofibers (CT-g-PAA/O-ECNFs) was prepared by an in situ grafting polymerization process. The prepared hydrogel nanocomposite was used as a novel effective and highly reusable adsorbent for the removal of methylene blue (MB) from polluted water with low cost. The morphology and the structure of CT-g-PAA/O-ECNFs were investigated by numerous techniques. The effect of incorporating O-ECNFs on the swelling capability of the prepared hydrogel was explored in distillated water and MB solution at normal pH. The effect of parameters including ratio of O-ECNFs, contact time, pH, initial concentration, and temperature on adsorption process were explored. The adsorption isot...

Research paper thumbnail of Fabrication of biohybrid electrospun nanofibers for the eradication of wound infection and drug-resistant pathogens

Colloids and Surfaces A: Physicochemical and Engineering Aspects

Research paper thumbnail of Fabrication of Sustained Release System of Electrospun Poly(acrylic acid)/Dextran Nanofibers Using Emulsion Electrospinning as Wound Dressing Applications

Journal of Nanoscience and Nanotechnology

The burst release of drug is a problem associated with the use of common blending electrospinning... more The burst release of drug is a problem associated with the use of common blending electrospinning. This problem can be avoided via fabrication of core–shell nanofibers where drug can be coated with polymer nanofibers as a shell. Moreover, there is a need to provide wound dressing with prolonged system of sustained release to accelerate the recovery of the wound. Currently, electrospun ciprofloxacin loaded poly(acrylic acid)/Dextran (Cipro@PAA/Dex) core–shell nanofibers can be prepared in green method using emulsion electrospinning. For comparison study, blend electrospun nanofibers (Cipro/PAA/Dex) was also prepared. The entrapment of drug into the polymeric material and the interaction between polymer blends were confirmed by FT-IR. Moreover, DSC was used to identify the type of interaction between polymeric chains. Field emission scanning electron microscope (FE-SEM) was used to study the nanofiber morphology and transmission electron microscope (TEM) and confocal laser scanning mi...

Research paper thumbnail of Synthesis of aminated electrospun carbon nanofibers and their application in removal of cationic dye

Materials Research Bulletin

Research paper thumbnail of Wound dressing properties of functionalized environmentally biopolymer loaded with selenium nanoparticles

Journal of Molecular Structure

Research paper thumbnail of Fabrication of functionalized electrospun carbon nanofibers for enhancing lead-ion adsorption from aqueous solutions

Scientific Reports

Electrospinning technique is a simple and cheap method for fabrication of electrospun nanofibers ... more Electrospinning technique is a simple and cheap method for fabrication of electrospun nanofibers (ENFs), which in turn can converted into electrospun carbon nanofibers (ECNFs) by carbonization process. The controlling of the ECNFs properties (e.g. surface area, porosity, diameters) during fabrication, make it superior over the other carbon nanomaterials. The aim of our study is to modify the surface of ECNFs to increase its hydrophilicity and in turn its efficiency in removing lead ions (Pb2+) from aqueous systems. The surface modification was carried out in two steps starting from oxidation of pristine ECNFs to produce oxidized ECNFs (o-ECNFs), followed by covalently bonded of melamine, and poly(m-phenylene diamine) for forming melamine-functionalized ECNFs (melam-ECNFs) and poly(m-phenylene diamine)-functionalized ECNFs (PmPDA-ECNFs), respectively. The as-prepared materials were characterized in routine way. The ability of the as-prepared materials towards adsorption of Pb2+ ions ...

Research paper thumbnail of Single-nozzle Core-shell Electrospun Nanofibers of PVP/Dextran as Drug Delivery System

Fibers and Polymers

Ciprofloxacin-loaded poly(vinylpyrrolidinone) (PVP) and dextran sulfate (Dex) (PVP/Dex) nanofiber... more Ciprofloxacin-loaded poly(vinylpyrrolidinone) (PVP) and dextran sulfate (Dex) (PVP/Dex) nanofibers were prepared using the emulsion electrospinning method. The physical and morphological characteristics of the prepared nanofibers were evaluated by conducting a Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The polymer-polymer and polymer-drug interactions were determined using differential scanning calorimetry (DSC). Moreover, the formation of the core-shell structure was confirmed by transmission electron microscopy (TEM) and confocal laser microscopy. The sustained release behavior was evaluated using ultraviolet-visible (UV-vis) spectroscopy, and its kinetic mechanism was investigated using Korsmeyer-Peppas, Peppas-Sahlin, and Weibull models by a non-linear regression equation. The antibacterial properties were evaluated using the disc diffusion method with respect to several wound gram-positive (Methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Staphylococcus aureus, and Klebsiella pneumoniae) and gram-negative bacteria (Pseudomonas aeruginosa, Salmonella typhimurium, and Proteus vulgaris). In general, the release behavior of Ciprofloxacin from PVP/Dex is controlled by diffusion in the delivery system.

Research paper thumbnail of Facile coprecipitation synthesis of nickel doped copper oxide nanocomposite as electrocatalyst for methanol electrooxidation in alkaline solution

Materials Research Express

A nickel doped copper oxide (Ni–CuO) nanocomposite is prepared by the coprecipitation method for ... more A nickel doped copper oxide (Ni–CuO) nanocomposite is prepared by the coprecipitation method for use as an electrocatalyst. The physicochemical properties of the synthesized electrocatalyst are characterized by powder XRD analysis, Fourier transform-infrared spectroscopy, field-emission scanning electron microscopy, high-resolution transmission electron microscopy, and N2 sorption measurements. The electrocatalytic performance of the Ni–CuO nanocomposite with respect to the electrochemical oxidation of methanol in an alkaline medium is evaluated through cyclic voltammetry and chronopotentiometry measurements. The reaction involving the electrooxidation of methanol is investigated comprehensively by varying experimental parameters such as the amount of catalyst used and the methanol solution concentration. The superior electrocatalytic activity of the Ni–CuO nanocomposite is attributable to its surface morphology and the presence of a large number of catalytically active sites on the nanocomposite surface. The results of this study suggest that the synthesized Ni–CuO nanocomposite should be suitable for use as an economical and abundant electrocatalyst in direct methanol fuel cells.

Research paper thumbnail of Alkali-activated electrospun carbon nanofibers as an efficient bifunctional adsorbent for cationic and anionic dyes

Colloids and Surfaces A: Physicochemical and Engineering Aspects

Abstract Activated electrospun carbon nanofibers (A-ECNFs) with micro/mesoporous structures and h... more Abstract Activated electrospun carbon nanofibers (A-ECNFs) with micro/mesoporous structures and high surface areas (1615 m2 g−1) were prepared using electrospinning technique followed by carbonization and alkali activation. The adsorption of Congo red (CR) and methylene blue (MB) dyes by A-ECNFs from aqueous solutions was investigated and compared with those of pristine ECNFs. The textural characteristics and morphology of the prepared pristine and activated ECNFs were characterized using various techniques. The adsorption performance was found to be associated to the surface area, porosity, and surface charges of the prepared adsorbents, the nature and molecular size of the dyes, and the pH and temperature of the solution. Six nonlinear isotherm models were applied to analyze the adsorption equilibrium data, and the results showed that the adsorption behavior could be appropriately described using the Redlich–Peterson isotherm model. The kinetic results for the adsorption of CR and MB onto A-ECNFs were fitted reasonably well to the Elovich model and were fitted by a pseudo-second order (PSO) model onto the pristine ECNFs. According to the thermodynamic results, the adsorption of CR and MB onto the A-ECNFs was endothermic and spontaneous. In addition, the reusability of the A-ECNFs was evaluated over five adsorption-desorption cycles.

Research paper thumbnail of Platinum nanoparticle decorated rutile titania synthesized by surfactant free hydrothermal method for visible light catalysis for dye degradation and hydrogen production study

International Journal of Hydrogen Energy

Abstract Rutile phase of titanium oxide and platinum nanoparticle decorated rutile titania is pre... more Abstract Rutile phase of titanium oxide and platinum nanoparticle decorated rutile titania is prepared by a surfactant free hydrothermal process in acidic condition. The pure rutile phase of TiO2 particle is forms the specific cauliflower morphology. Hydrothermal process in presence of specific acid addition led to the formation of cauli-flower shaped rutile phase of titania. The efficiency and solar assisted photo catalytic ability of these materials are tested for methylene blue degradation as well as hydrogen generation by methanol reforming process. The X-ray diffraction of pattern of pure rutile phase formation is confirmed by reported JCPDS data. The surface physico-chemical property of prepared rutile Titania is further characterized by BET, Raman and SEM analysis. The HR-TEM of the prepared samples show the reduced particle size for rutile titania and studied their morphology in detail. Solar light assisted methylene blue degradation reaction was carrying out to study the catalytic efficiency towards dye degradation and kinetic activity of the same for prepared commercial titania and pure rutile TiO2. The platinum loaded and photo deposited rutile Titania is further analyzed for hydrogen production reaction by methanol reforming process. The rate of hydrogen evolution on platinum nanoparticle photo deposited on reforming process shows more than 900 μmol/g compared to pristine rutile titania catalysts.

Research paper thumbnail of Effective adsorption of Coomassie brilliant blue dye using poly(phenylene diamine)grafted electrospun carbon nanofibers as a novel adsorbent

Materials Chemistry and Physics

Abstract Grafting of poly(para-, ortho- and meta-phenylenediamine (PPDA)) onto electrospun carbon... more Abstract Grafting of poly(para-, ortho- and meta-phenylenediamine (PPDA)) onto electrospun carbon nanofibers was performed via oxidative polymerization of o-, p-, m-PDA onto the surface of ECNFs to produce PPDA-g-ECNFs. The well characterized PPDA-g-ECNFs and their precursors were applied as effective nanoadsorbent for the removal of Coomassie brilliant blue R-250 (CBB) from aqueous solutions. The obtained results indicated that the surface modification of ECNFs by conjugated polymers enhanced its adsorption capacity with respect to CBB and was dependent on the nature of surface functionalization, concentration of CBB, pH, and contact time. The equilibrium isotherm and kinetic parameters on the adsorption of CBB onto the functionalized ECNFs were evaluated and analyzed by non-linear isotherm and kinetic models. The results of the kinetic and isotherm studies revealed that the Elovich kinetic model and the Redlich–Peterson isotherm model were more suitable to describe the adsorption of CBB from an aqueous solution. Furthermore, the thermodynamic parameters exhibited spontaneity of CBB adsorption and its endothermic characteristic, thereby demonstrating the high efficiency of the introduced adsorbents for CBB adsorption. A possible mechanism of adsorption was suggested wherein electrostatic interaction, π–π interactions, and intermolecular H-bonding control the CBB adsorption.

Research paper thumbnail of Effective synthesis of some novel pyrazolidine-3,5-dione derivatives via Mg(II) catalyzed in water medium and their anticancer and antimicrobial activities

Molecular Diversity

Novel pyrazolidine-3,5-dione derivatives (2a–g, 4a–g, and 6a–g) were synthesized by an easy-to-pe... more Novel pyrazolidine-3,5-dione derivatives (2a–g, 4a–g, and 6a–g) were synthesized by an easy-to-perform Mg(II) acetylacetonate-catalyzed reaction with high yields using water as the reaction medium. Synthesized compounds were screened for anticancer and antimicrobial activities. The compound 6c (LD50 19.1 µg/mL) showed anticancer activity higher than that of all other compounds against MCF-7 breast cancer cell line. Results of antimicrobial activities revealed that the compound 4d (MIC 0.5 μg/mL) had higher activity than ciprofloxacin against Staphylococcus aureus, whereas the compound 2b (MIC 0.5 μg/mL) had higher activity than clotrimazole against Candida albicans. Overall results of this study envisaged that the compounds 2b, 4d, and 6c have the potential to be developed as anticancer and antimicrobial agents.Graphical abstractNovel pyrazolidine-3,5-dione derivatives (2a–g, 4a–g, and 6a–g) were synthesized via an easy-to perform Mg(II) catalysis in water medium. The synthesized compounds were screened for anticancer and antimicrobial activities.

Research paper thumbnail of Synthesis, crystal structure, DFT calculations and antimicrobial activity of 4-(4-Fluoro-phenyl)-2,6-dimethyl-1,4-dihydro-pyridine-3,5-dicarboxylic acid diethyl ester

The title compound was synthesized and confirmed by FT-IR, H, C NMR analysis. The molecular struc... more The title compound was synthesized and confirmed by FT-IR, H, C NMR analysis. The molecular structure of the compound was precisely determined by Single Crystal X-ray Diffraction (SC-XRD) analysis. The crystalized compound shows P21/C & monoclinic crystal system with cell parameters a = 9.7768 (5), b = 7.4005(3) and c = 24.8099 (12), β=93.734(2)°.The structural and electronic properties of the compound were carried out by Density Functional Theory (DFT) calculations. The compound exhibited H-bonding between N1-H1A-----O1 with bond distance 2.98(7) A°).The energy gap Egap 4.53eV and Egap= 4.34eV for crystal and DFT method respectively. The molecular orbitals energies were studied through Highest Unoccupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) analysis. The softness and hardness of the molecule was studied through Global Chemical Reactivity Descriptors (GCRD). The electrophilic and nucleophilic characters were studied through Molecular Electrostatic ...

Research paper thumbnail of Fabrication, microstructure characterization and degradation performance of electrospun mats based on poly(3‐hydroxybutyrate‐ co ‐3 hydroxyvalerate)/polyethylene glycol blend for potential tissue engineering

Research paper thumbnail of Synthesis, crystal structure, quantum calculation and Hirshfeld surface analysis of 4-bromoanilinium oxalate hemihydrate single crystal

Journal of Molecular Structure

Research paper thumbnail of Recent Advantages of Biopolymer Preparation and Applications in Bio-Industry

Research paper thumbnail of Biocidal Polymers: Synthesis, Characterization and Antimicrobial Activity of Bis-Quaternary Onium Salts of Poly(aspartate-co-succinimide)

Polymers

Microbial multidrug resistance presents a real problem to human health. Therefore, water-soluble ... more Microbial multidrug resistance presents a real problem to human health. Therefore, water-soluble polymers based on poly(aspartate-co-succinimide) were synthesized via reaction of poly(aspartate-co-succinimide) with bis-quaternary ammonium or quaternary salts. The resultant copolymers were characterized by various techniques such as FTIR, TGA, 1HNMR, 13CNMR and elemental microanalysis. Antimicrobial activities of the new onium salts were investigated against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella typhi, and the fungi; Candida albicans,Aspergillus niger, Cryptococcus neoformans and Aspergillus flavus by agar diffusion method. Antimicrobial activity was studied in terms of inhibition zone diameters, in addition to the estimation of minimal inhibitory concentration (MIC) of the prepared compounds. A. niger and E. coli were the most affected microorganisms among the tested microorganisms with an inhibition zone of 19–21 (mm) in case of biocides, (...

Research paper thumbnail of Modified Electrospun Polymeric Nanofibers and Their Nanocomposites as Nanoadsorbents for Toxic Dye Removal from Contaminated Waters: A Review

Polymers

Electrospun polymer nanofibers (EPNFs) as one-dimensional nanostructures are characterized by a h... more Electrospun polymer nanofibers (EPNFs) as one-dimensional nanostructures are characterized by a high surface area-to-volume ratio, high porosity, large number of adsorption sites and high adsorption capacity. These properties nominate them to be used as an effective adsorbent for the removal of water pollutants such as heavy metals, dyes and other pollutants. Organic dyes are considered one of the most hazardous water pollutants due to their toxic effects even at very low concentrations. To overcome this problem, the adsorption technique has proven its high effectiveness towards the removal of such pollutants from aqueous systems. The use of the adsorption technique depends mainly on the properties, efficacy, cost and reusability of the adsorbent. So, the use of EPNFs as adsorbents for dye removal has received increasing attention due to their unique properties, adsorption efficiency and reusability. Moreover, the adsorption efficiency and stability of EPNFs in aqueous media can be ...

Research paper thumbnail of Synthesis of lanthanide‐doped strontium aluminate nanoparticles encapsulated in polyacrylonitrile nanofibers: Photoluminescence properties for anti‐counterfeiting applications

Luminescence

Photochromism has been applied as an interesting technique to improve the anti-counterfeiting of ... more Photochromism has been applied as an interesting technique to improve the anti-counterfeiting of commercial commodities. In order to build up a mechanically reliable anti-counterfeiting nanocomposite, it has been vital to enhance the engineering process of the anti-counterfeiting material. In the current study, we developed mechanically reliable and highly photoluminescent lanthanide-doped strontium aluminate nanoparticles (LSAN)/polyacrylonitrile (PAN) hybrid nanofibers successfully fabricated by electrospinning technique for anti-counterfeiting applications. The produced nanocomposite films exhibited ultraviolet-induced photochromic anti-counterfeiting property. In order to guarantee the transparent of the LSAN-PAN film, LSAN must be immobilized into the nanoparticle size to allow better dispersion without aggregation in the polyacrylonitrile matrix. The LSAN-PAN nanofibrous film demonstrated absorbance intensity at 354 nm associated with an emission intensity at 424 nm. The produced LSAN-PAN films demonstrated an enhanced hydrophobicity with increasing the ratio of LSAN without adversely influence their native appearance and mechanical performance. Upon excitation with ultraviolet, the translucent nanofibrous substrates exhibited fast and reversible photochromic activity to greenish-yellow without exhaustion. The nanofibrous films exhibited stretchability, transparency, flexibility and ultraviolet-induced photochromism at low-cost. The current strategy can be considered as an efficient technique toward the development of various anti-counterfeiting materials for a better market with economic and social values.

Research paper thumbnail of Enhancement the electrical conductivity of the synthesized polyvinylidene fluoride/polyvinyl chloride composite doped with palladium nanoparticles via laser ablation

Journal of Materials Research and Technology

Research paper thumbnail of In Situ Preparation of Novel Porous Nanocomposite Hydrogel as Effective Adsorbent for the Removal of Cationic Dyes from Polluted Water

Polymers

The use of some hydrogels as adsorbents for pollutants removal from wastewater is limited due to ... more The use of some hydrogels as adsorbents for pollutants removal from wastewater is limited due to their high swelling properties and the difficulty in recovering them after the adsorption process. To overcome these problems, a new hydrogel nanocomposite based on chitosan-grafted-polyacrylic acid/oxidized electrospun carbon nanofibers (CT-g-PAA/O-ECNFs) was prepared by an in situ grafting polymerization process. The prepared hydrogel nanocomposite was used as a novel effective and highly reusable adsorbent for the removal of methylene blue (MB) from polluted water with low cost. The morphology and the structure of CT-g-PAA/O-ECNFs were investigated by numerous techniques. The effect of incorporating O-ECNFs on the swelling capability of the prepared hydrogel was explored in distillated water and MB solution at normal pH. The effect of parameters including ratio of O-ECNFs, contact time, pH, initial concentration, and temperature on adsorption process were explored. The adsorption isot...

Research paper thumbnail of Fabrication of biohybrid electrospun nanofibers for the eradication of wound infection and drug-resistant pathogens

Colloids and Surfaces A: Physicochemical and Engineering Aspects

Research paper thumbnail of Fabrication of Sustained Release System of Electrospun Poly(acrylic acid)/Dextran Nanofibers Using Emulsion Electrospinning as Wound Dressing Applications

Journal of Nanoscience and Nanotechnology

The burst release of drug is a problem associated with the use of common blending electrospinning... more The burst release of drug is a problem associated with the use of common blending electrospinning. This problem can be avoided via fabrication of core–shell nanofibers where drug can be coated with polymer nanofibers as a shell. Moreover, there is a need to provide wound dressing with prolonged system of sustained release to accelerate the recovery of the wound. Currently, electrospun ciprofloxacin loaded poly(acrylic acid)/Dextran (Cipro@PAA/Dex) core–shell nanofibers can be prepared in green method using emulsion electrospinning. For comparison study, blend electrospun nanofibers (Cipro/PAA/Dex) was also prepared. The entrapment of drug into the polymeric material and the interaction between polymer blends were confirmed by FT-IR. Moreover, DSC was used to identify the type of interaction between polymeric chains. Field emission scanning electron microscope (FE-SEM) was used to study the nanofiber morphology and transmission electron microscope (TEM) and confocal laser scanning mi...

Research paper thumbnail of Synthesis of aminated electrospun carbon nanofibers and their application in removal of cationic dye

Materials Research Bulletin

Research paper thumbnail of Wound dressing properties of functionalized environmentally biopolymer loaded with selenium nanoparticles

Journal of Molecular Structure

Research paper thumbnail of Fabrication of functionalized electrospun carbon nanofibers for enhancing lead-ion adsorption from aqueous solutions

Scientific Reports

Electrospinning technique is a simple and cheap method for fabrication of electrospun nanofibers ... more Electrospinning technique is a simple and cheap method for fabrication of electrospun nanofibers (ENFs), which in turn can converted into electrospun carbon nanofibers (ECNFs) by carbonization process. The controlling of the ECNFs properties (e.g. surface area, porosity, diameters) during fabrication, make it superior over the other carbon nanomaterials. The aim of our study is to modify the surface of ECNFs to increase its hydrophilicity and in turn its efficiency in removing lead ions (Pb2+) from aqueous systems. The surface modification was carried out in two steps starting from oxidation of pristine ECNFs to produce oxidized ECNFs (o-ECNFs), followed by covalently bonded of melamine, and poly(m-phenylene diamine) for forming melamine-functionalized ECNFs (melam-ECNFs) and poly(m-phenylene diamine)-functionalized ECNFs (PmPDA-ECNFs), respectively. The as-prepared materials were characterized in routine way. The ability of the as-prepared materials towards adsorption of Pb2+ ions ...

Research paper thumbnail of Single-nozzle Core-shell Electrospun Nanofibers of PVP/Dextran as Drug Delivery System

Fibers and Polymers

Ciprofloxacin-loaded poly(vinylpyrrolidinone) (PVP) and dextran sulfate (Dex) (PVP/Dex) nanofiber... more Ciprofloxacin-loaded poly(vinylpyrrolidinone) (PVP) and dextran sulfate (Dex) (PVP/Dex) nanofibers were prepared using the emulsion electrospinning method. The physical and morphological characteristics of the prepared nanofibers were evaluated by conducting a Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The polymer-polymer and polymer-drug interactions were determined using differential scanning calorimetry (DSC). Moreover, the formation of the core-shell structure was confirmed by transmission electron microscopy (TEM) and confocal laser microscopy. The sustained release behavior was evaluated using ultraviolet-visible (UV-vis) spectroscopy, and its kinetic mechanism was investigated using Korsmeyer-Peppas, Peppas-Sahlin, and Weibull models by a non-linear regression equation. The antibacterial properties were evaluated using the disc diffusion method with respect to several wound gram-positive (Methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Staphylococcus aureus, and Klebsiella pneumoniae) and gram-negative bacteria (Pseudomonas aeruginosa, Salmonella typhimurium, and Proteus vulgaris). In general, the release behavior of Ciprofloxacin from PVP/Dex is controlled by diffusion in the delivery system.

Research paper thumbnail of Facile coprecipitation synthesis of nickel doped copper oxide nanocomposite as electrocatalyst for methanol electrooxidation in alkaline solution

Materials Research Express

A nickel doped copper oxide (Ni–CuO) nanocomposite is prepared by the coprecipitation method for ... more A nickel doped copper oxide (Ni–CuO) nanocomposite is prepared by the coprecipitation method for use as an electrocatalyst. The physicochemical properties of the synthesized electrocatalyst are characterized by powder XRD analysis, Fourier transform-infrared spectroscopy, field-emission scanning electron microscopy, high-resolution transmission electron microscopy, and N2 sorption measurements. The electrocatalytic performance of the Ni–CuO nanocomposite with respect to the electrochemical oxidation of methanol in an alkaline medium is evaluated through cyclic voltammetry and chronopotentiometry measurements. The reaction involving the electrooxidation of methanol is investigated comprehensively by varying experimental parameters such as the amount of catalyst used and the methanol solution concentration. The superior electrocatalytic activity of the Ni–CuO nanocomposite is attributable to its surface morphology and the presence of a large number of catalytically active sites on the nanocomposite surface. The results of this study suggest that the synthesized Ni–CuO nanocomposite should be suitable for use as an economical and abundant electrocatalyst in direct methanol fuel cells.

Research paper thumbnail of Alkali-activated electrospun carbon nanofibers as an efficient bifunctional adsorbent for cationic and anionic dyes

Colloids and Surfaces A: Physicochemical and Engineering Aspects

Abstract Activated electrospun carbon nanofibers (A-ECNFs) with micro/mesoporous structures and h... more Abstract Activated electrospun carbon nanofibers (A-ECNFs) with micro/mesoporous structures and high surface areas (1615 m2 g−1) were prepared using electrospinning technique followed by carbonization and alkali activation. The adsorption of Congo red (CR) and methylene blue (MB) dyes by A-ECNFs from aqueous solutions was investigated and compared with those of pristine ECNFs. The textural characteristics and morphology of the prepared pristine and activated ECNFs were characterized using various techniques. The adsorption performance was found to be associated to the surface area, porosity, and surface charges of the prepared adsorbents, the nature and molecular size of the dyes, and the pH and temperature of the solution. Six nonlinear isotherm models were applied to analyze the adsorption equilibrium data, and the results showed that the adsorption behavior could be appropriately described using the Redlich–Peterson isotherm model. The kinetic results for the adsorption of CR and MB onto A-ECNFs were fitted reasonably well to the Elovich model and were fitted by a pseudo-second order (PSO) model onto the pristine ECNFs. According to the thermodynamic results, the adsorption of CR and MB onto the A-ECNFs was endothermic and spontaneous. In addition, the reusability of the A-ECNFs was evaluated over five adsorption-desorption cycles.

Research paper thumbnail of Platinum nanoparticle decorated rutile titania synthesized by surfactant free hydrothermal method for visible light catalysis for dye degradation and hydrogen production study

International Journal of Hydrogen Energy

Abstract Rutile phase of titanium oxide and platinum nanoparticle decorated rutile titania is pre... more Abstract Rutile phase of titanium oxide and platinum nanoparticle decorated rutile titania is prepared by a surfactant free hydrothermal process in acidic condition. The pure rutile phase of TiO2 particle is forms the specific cauliflower morphology. Hydrothermal process in presence of specific acid addition led to the formation of cauli-flower shaped rutile phase of titania. The efficiency and solar assisted photo catalytic ability of these materials are tested for methylene blue degradation as well as hydrogen generation by methanol reforming process. The X-ray diffraction of pattern of pure rutile phase formation is confirmed by reported JCPDS data. The surface physico-chemical property of prepared rutile Titania is further characterized by BET, Raman and SEM analysis. The HR-TEM of the prepared samples show the reduced particle size for rutile titania and studied their morphology in detail. Solar light assisted methylene blue degradation reaction was carrying out to study the catalytic efficiency towards dye degradation and kinetic activity of the same for prepared commercial titania and pure rutile TiO2. The platinum loaded and photo deposited rutile Titania is further analyzed for hydrogen production reaction by methanol reforming process. The rate of hydrogen evolution on platinum nanoparticle photo deposited on reforming process shows more than 900 μmol/g compared to pristine rutile titania catalysts.

Research paper thumbnail of Effective adsorption of Coomassie brilliant blue dye using poly(phenylene diamine)grafted electrospun carbon nanofibers as a novel adsorbent

Materials Chemistry and Physics

Abstract Grafting of poly(para-, ortho- and meta-phenylenediamine (PPDA)) onto electrospun carbon... more Abstract Grafting of poly(para-, ortho- and meta-phenylenediamine (PPDA)) onto electrospun carbon nanofibers was performed via oxidative polymerization of o-, p-, m-PDA onto the surface of ECNFs to produce PPDA-g-ECNFs. The well characterized PPDA-g-ECNFs and their precursors were applied as effective nanoadsorbent for the removal of Coomassie brilliant blue R-250 (CBB) from aqueous solutions. The obtained results indicated that the surface modification of ECNFs by conjugated polymers enhanced its adsorption capacity with respect to CBB and was dependent on the nature of surface functionalization, concentration of CBB, pH, and contact time. The equilibrium isotherm and kinetic parameters on the adsorption of CBB onto the functionalized ECNFs were evaluated and analyzed by non-linear isotherm and kinetic models. The results of the kinetic and isotherm studies revealed that the Elovich kinetic model and the Redlich–Peterson isotherm model were more suitable to describe the adsorption of CBB from an aqueous solution. Furthermore, the thermodynamic parameters exhibited spontaneity of CBB adsorption and its endothermic characteristic, thereby demonstrating the high efficiency of the introduced adsorbents for CBB adsorption. A possible mechanism of adsorption was suggested wherein electrostatic interaction, π–π interactions, and intermolecular H-bonding control the CBB adsorption.

Research paper thumbnail of Effective synthesis of some novel pyrazolidine-3,5-dione derivatives via Mg(II) catalyzed in water medium and their anticancer and antimicrobial activities

Molecular Diversity

Novel pyrazolidine-3,5-dione derivatives (2a–g, 4a–g, and 6a–g) were synthesized by an easy-to-pe... more Novel pyrazolidine-3,5-dione derivatives (2a–g, 4a–g, and 6a–g) were synthesized by an easy-to-perform Mg(II) acetylacetonate-catalyzed reaction with high yields using water as the reaction medium. Synthesized compounds were screened for anticancer and antimicrobial activities. The compound 6c (LD50 19.1 µg/mL) showed anticancer activity higher than that of all other compounds against MCF-7 breast cancer cell line. Results of antimicrobial activities revealed that the compound 4d (MIC 0.5 μg/mL) had higher activity than ciprofloxacin against Staphylococcus aureus, whereas the compound 2b (MIC 0.5 μg/mL) had higher activity than clotrimazole against Candida albicans. Overall results of this study envisaged that the compounds 2b, 4d, and 6c have the potential to be developed as anticancer and antimicrobial agents.Graphical abstractNovel pyrazolidine-3,5-dione derivatives (2a–g, 4a–g, and 6a–g) were synthesized via an easy-to perform Mg(II) catalysis in water medium. The synthesized compounds were screened for anticancer and antimicrobial activities.