The photochemical behavior of the phototoxic antidepressant drug venlafaxine (VLF, 1) was studied... more The photochemical behavior of the phototoxic antidepressant drug venlafaxine (VLF, 1) was studied under aerobic conditions in UV-A light. Irradiation of a phosphate buffer solution of the drug produces N-Demethylated (2) and O-Demethylated (3) as two major photoproducts. The formation of photoproducts (2) and (3) occurs through a singlet oxygen-mediated mechanism, i.e., type-II photodynamic action, involving an irreversible trapping of the self-photogenerated singlet molecular oxygen (1 O 2) and through free radical-mediated mechanism, i.e., type 1 photodynamic action, respectively. The generation of singlet oxygen and free radicals during photolysis was confirmed by singlet oxygen scavenger sodium azide (NaN 3) and free radical scavenger reduced glutathione (GSH). In addition, the comparative antioxidant potentials of the parent drug and its photoproducts were examined utilizing in-silico molecular docking against tyrosinase to better understand the in vivo relevance of drug pharmacological action as a result of drug-light interaction. Photoproduct (2) exhibited less activity as compared to the parent drug, VLF (1), whereas photoproduct (3) formed a stable protein-ligand complex. In order to determine the nature of stability of complex between protein and ligand, further, molecular dynamics (MD) simulation on photoproduct (3) was performed for 100 ns, and the results were analyzed by monitoring root mean square deviations (RMSD), the radius of gyration (Rg), and solvent accessible surface area (SASA). The results proved the formation of a better protein-ligand complex with photoproduct (3). These findings imply that drug users should avoid their exposure to light (natural or artificial) to prevent drug-induced photosensitivity. This study also opens new vistas for the development of novel drugs with desired tyrosinase binding affinity, improved biological features, and low phototoxic manifestations.
He has published 12 research papers in the areas of hybrid naocomposite materials, adsorption, po... more He has published 12 research papers in the areas of hybrid naocomposite materials, adsorption, polymer and potentiometric sensors in refereed international journals and 3 Book Chapters. He has presented several research papers at various national and international conferences. His areas of research include preparation, characterization and application of hybrid nano-composite materials, Thermodynamic and kinetics study of composite material, synthesis of potentiometric sensors for determination of toxic metals in water and their removal, Purification of water using synthesized nano-composite.
Due to its distinct and unique surface morphology, mechanical strength, tunable solubility in wat... more Due to its distinct and unique surface morphology, mechanical strength, tunable solubility in water, viscous properties, ease of access and enormous amount of raw materials, low-cost synthesis process and similarly several more opposing characteristics, carboxymethyl cellulose (CMC) based materials have wide applications. While synthesizing nanoparticles, CMC appears to be better as both a reducing and stabilizing agent. CMC would have no detrimental effects on human health or the environment and also is non-toxic and biodegradable. Hence, CMC mediated metal and metal oxide nanoparticles have multiple benefits in the areas of antibacterial, antimicrobial, antidiabetic, anti-inflammatory, wound healing, antioxidant, as well as optical properties. In this mini-review article, the role of carboxymethyl cellulose (CMC) is highligted in the fabrication of nanoparticles.
The present work describes the synthesis of copper oxide nanoparticles (CuONPs) via a solution pr... more The present work describes the synthesis of copper oxide nanoparticles (CuONPs) via a solution process with the aim of applying the nano-adsorbent for the reduction of methylene blue (MB) dye in alkaline media. These NPs were characterized via Field emission scanning electron microscopy (FE-SEM), X-ray diffraction, high-resolution Transmission electron microscopy (TEM), and ultra violet UV-visible spectroscopy to confirm their morphology and crystalline and optical properties in order to design an adsorption-degradation process. The photocatalytic CuONPs exhibited dynamic properties, great adsorption affinity during the chemisorption process, and operated at various modes with a strong interaction between the adsorbent and the adsorptive species, and equilibrium isotherm, kinetic isotherm, and thermodynamic activities in the presence of UV light. All basic quantities, such as concentration, pH, adsorbent dose, time, and temperature, were determined by an optimization process. The be...
Poly o-toluidine zirconium(IV) iodosulfosalicylate (PTZIS) is a hybrid inorganic–organic composit... more Poly o-toluidine zirconium(IV) iodosulfosalicylate (PTZIS) is a hybrid inorganic–organic composite cation exchanger, which was synthesized by mixing an organic compound, poly o-toluidine, into the matrices of zirconium(IV) iodosulfosalicylate. On the basis of distribution coefficient, Kd, the material was found to have high affinity for adsorption of Cr(III) ion. Due to its Cr(III) selective nature, ion exchanger was used as an electroactive material for preparation of an ion-selective membrane electrode. The physical properties of membrane were determined by XRD, SEM, and AFM analysis, which indicates that PVC-based Cr(III) ion-selective membrane is amorphous and porous in nature. The electrode responds to Cr(III) in a linear range from 3.16 × 10–6 to 1 × 10–1 M with a Nernstian slope of 22 ± 0.5 mV per decade change in concentration and a detection limit of 1.584 × 10–6 M. The life span of the electrode is found to be 12 weeks. The proposed electrode shows satisfactory performance over a pH range of 3.0...
ABSTRACT The present study explored the feasibility of using zirconium(IV) iodosulphosalicylate (... more ABSTRACT The present study explored the feasibility of using zirconium(IV) iodosulphosalicylate (ZIS) as adsorbent for the removal of lead(II) under different conditions. Batch studies were performed to evaluate the influence of various experimental parameters such as pH 7.5, adsorbent dose 200 mg or 10 g L−1 of solution and equilibrium time 120 min for the concentration range of 53.87–241.45 ppm at 323 K. A comparison of kinetic models applied to the adsorption of Pb (II) on ZIS was evaluated for the Lagergren pseudo first order, Ho and McKay pseudo second order, Elovich and intraparticle diffusion kinetic models. The experimental data fitted very well in pseudo second order followed by Elovich model. Intraparticle diffusion does not seem to control the Pb (II) removal process. Equilibrium isotherm for the adsorption of Pb (II) on ZIS was analyzed by Freundlich, Langmuir, Dubnin–Radushkevich (D–R) and Temkin isotherm model using linear regression technique. Langmuir and Freundlich isotherms were found to best represent the data for Pb (II) onto ZIS. The maximum adsorption capacity of ZIS is found to be 327.87 mg g−1 Pb (II). The results show that the sorption capacity increases with increase in temperature, concentration, pH but decreased with adsorbent dose. The thermodynamics parameters such as enthalpy change (ΔH° = 6797.23 J mol−1), entropy change (ΔS° = 29.333 J mol−1), Gibb's free energy (ΔG° = −2677.45 J mol−1) and activation energy (Ea = 8198.6 J mol−1) results indicate that adsorption process was spontaneous, endothermic nature, increased randomness and shows feasibility and good affinity of Pb (II) toward the adsorbent.
Zirconium(IV) phosphosulphosalicylate, a cation exchanger was synthesized by mixing zirconium oxy... more Zirconium(IV) phosphosulphosalicylate, a cation exchanger was synthesized by mixing zirconium oxychloride to a mixture of 5-sulphosalicylic acid and phosphoric acid. The material showed good efficiency for the preparation of an ion-selective membrane electrode. The membrane was characterized affinity for Pb(II) ions. Due to its Pb(II) selective nature, the ion-exchanger was used as an electroactive by XRD and SEM analysis. The electrode responds to Pb(II) ions in a linear range from 1 • 10 À5 to 1 • 10 À1 M with a slope of 43.8 mV per decade change in concentration with detection limit of 4.78 • 10 À6 M. The life span of electrode was found to be 90 days. The proposed electrode showed satisfactory performance over a pH range of 4.0-6.5, with a fast response time of 15 s. The sensor has been applied to the determination of Pb(II) ions in water samples of different origins. It has also been used as indicator electrode in potentiometric titration of Pb(II) ion with EDTA.
ABSTRACT The UV–visible spectrophotometric method has been described the study of raw carbon nano... more ABSTRACT The UV–visible spectrophotometric method has been described the study of raw carbon nanotubes (R-MWCNTs) and functionalized multiwall carbon nanotubes (F-MWCNTs) for the control of bacterial growth by using validated analytical techniques. The absorption spectra of functionalized carbon nanotubes (F-MWCNTs) and raw carbon nanotubes (R-MWCNTs) show maximum absorbance at λ max 600 nm. The linear relationship was found between absorbance and concentration of R-MWCNTs and F-MWCNTs in the range of 0.25–2.0 μg mL−1. The linear regression equation was evaluated by statistical treatment of calibration data and gives the value of correlation coefficient for F-MWCNTs (0.9999) and R-MWCNTs (0.9993), which indicate excellent linearity. The Optical and regression characteristics of the proposed method were found apparent molar absorptivity, limits of detection (LOD), and limit of quantitation (LOQ) for R-MWCNTs and F-MWCNTs (5.75 × 102: 8.25 × 102 L mol−1 cm−1), (0.052: 0.018 μg mL−1), and (0.055: 0.158 μg mL−1), respectively. The validity of the proposed method was checked by precision, accuracy, linearity, limits of detection (LOD), and limit of quantitation (LOQ). The RSD (%) and quantitative recoveries (%) were obtained (0.026–0.0086) and (100.34 and 100.71) for R-MWCNTs: for F-MWCNTs by UV–visible spectrophotometric, respectively.
The present work describes the synthesis of copper oxide nanoparticles (CuONPs) via a solution pr... more The present work describes the synthesis of copper oxide nanoparticles (CuONPs) via a solution process with the aim of applying the nano-adsorbent for the reduction of methylene blue (MB) dye in alkaline media. These NPs were characterized via Field emission scanning electron microscopy (FE-SEM), X-ray diffraction, high-resolution Transmission electron microscopy (TEM), and ultra violet UV-visible spectroscopy to confirm their morphology and crystalline and optical properties in order to design an adsorption-degradation process. The photocatalytic CuONPs exhibited dynamic properties, great adsorption affinity during the chemisorption process, and operated at various modes with a strong interaction between the adsorbent and the adsorptive species, and equilibrium isotherm, kinetic isotherm, and thermodynamic activities in the presence of UV light. All basic quantities, such as concentration, pH, adsorbent dose, time, and temperature, were determined by an optimization process. The best-fitted adsorption Langmuir model (R 2 = 0.9988) and performance, including adsorption capacity (350.87 mg/g), photocatalytic efficiency (90.74%), and degradation rate constant (Ks = 2.23 ×10 −2 min −1), illustrate good feasibility with respect to sorption-reduction reactions but followed a pseudo-second-order kinetic on the adsorbent surface, reaching an equilibrium point in 80 min. The thermodynamic analysis suggests that the adsorption reaction is spontaneous and endothermic in nature. The thermodynamic parameters such as enthalpy (∆H°), entropy (∆S°), and Gibbs free energy (∆G°) give effective results to support a chemical reduction reaction at 303 K temperature. The equilibrium isotherm and kinetic and thermodynamic models with error function analysis explore the potential, acceptability, accuracy, access to adsorbents, and novelty of an unrivaled-sorption system.
Poly o-toluidine zirconium(IV) iodosulfosalicylate (PTZIS) is a hybrid inorganic−organic composit... more Poly o-toluidine zirconium(IV) iodosulfosalicylate (PTZIS) is a hybrid inorganic−organic composite cation exchanger, which was synthesized by mixing an organic compound, poly o-toluidine, into the matrices of zirconium(IV) iodosulfosalicylate. On the basis of distribution coefficient, K d , the material was found to have high affinity for adsorption of Cr(III) ion. Due to its Cr(III) selective nature, ion exchanger was used as an electroactive material for preparation of an ionselective membrane electrode. The physical properties of membrane were determined by XRD, SEM, and AFM analysis, which indicates that PVC-based Cr(III) ion-selective membrane is amorphous and porous in nature. The electrode responds to Cr(III) in a linear range from 3.16 × 10 −6 to 1 × 10 −1 M with a Nernstian slope of 22 ± 0.5 mV per decade change in concentration and a detection limit of 1.584 × 10 −6 M. The life span of the electrode is found to be 12 weeks. The proposed electrode shows satisfactory performance over a pH range of 3.0−7.0, with a fast response time of 10s. The sensor has been applied to determination of Cr(III) ions in water samples of different origins. The sensor has been used as an indicator electrode in potentiometric titrations of Cr(III) ion with EDTA.
Various samples of zirconium(IV) iodosulphosalicylate have been synthesized under varying mixing ... more Various samples of zirconium(IV) iodosulphosalicylate have been synthesized under varying mixing ratios of aqueous solutions of 0.1 M zirconium oxychloride, 0.1 M potassium iodate and 0.1 M 5-sulphosalicylaic acid at pH 1. The material showed ion-exchange capacity of 1.58 meqg −1 for K + . pH titration curve indicated its monofunctional behavior. On the basis of chemical composition, FTIR and thermogravimetric analysis the tentative formula was proposed as (ZrO) 2 (HIO 3 )(C 6 H 3 COOH · OH · SO 3 H)(OH) 4 · nH 2 O. The distribution coefficient values of 15 metal ions have been determined in distilled water and different concentrations of HNO 3 . The material is highly selective for Pb(II). The adsorption behavior of Pb(II), Th(IV), Al(III) and Cu(II) on the material was studied. Negative values of G at all temperatures (293, 303 and 313 K) indicated the feasibility and spontaneity of the adsorption process. Positive values of S confirmed the randomness of the adsorption process. The removal efficiency of Pb(II) from a synthetic mixture of metal ions such as Mg(II), Ca(II), Sr(II), Ba(II), Cd(II), Mn(II), Zn(II), Co(II), Cu(II), Fe(III), Al(III) and Ni(II) has been demonstrated.
Poly-o-toluidine zirconium(IV) iodosulphosalicylate Ion-exchange capacity Cr(III) selectivity Pse... more Poly-o-toluidine zirconium(IV) iodosulphosalicylate Ion-exchange capacity Cr(III) selectivity Pseudo first order kinetic model Particle diffusion controlled A B S T R A C T An organic-inorganic composite poly-o-toluidine zirconium(IV) iodosulphosalicylate has been synthesized by mixing poly-o-toluidine into the gel of zirconium(IV) iodosulphosalicylate. The physicochemical properties of the material were characterized by FTIR, X-ray, TGA-DTA, SEM, TEM and EDX analysis. The ion-exchange capacity and chemical stability were determined. The adsorption efficiency toward heavy metal ions was determined and material was found to be highly selective for Cr(III). The thermodynamics and kinetics of the sorption of Cr(III) were studied. Adsorption of Cr(III) was explained by pseudo-first order kinetic model. The analytical utility of the material was demonstrated by achieving separation of Cr(III) from other metal ions.
Zirconium(IV) phosphosulphosalicylate, a cation exchanger was synthesized by mixing zirconium oxy... more Zirconium(IV) phosphosulphosalicylate, a cation exchanger was synthesized by mixing zirconium oxychloride to a mixture of 5-sulphosalicylic acid and phosphoric acid. The material showed good efficiency for the preparation of an ion-selective membrane electrode. The membrane was characterized affinity for Pb(II) ions. Due to its Pb(II) selective nature, the ion-exchanger was used as an electroactive by XRD and SEM analysis. The electrode responds to Pb(II) ions in a linear range from 1 · 10 À5 to 1 · 10 À1 M with a slope of 43.8 mV per decade change in concentration with detection limit of 4.78 · 10 À6 M. The life span of electrode was found to be 90 days. The proposed electrode showed satisfactory performance over a pH range of 4.0-6.5, with a fast response time of 15 s. The sensor has been applied to the determination of Pb(II) ions in water samples of different origins. It has also been used as indicator electrode in potentiometric titration of Pb(II) ion with EDTA. ª 2015 The Authors. Production and hosting by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
The present study explored the feasibility of using zirconium(IV) iodosulphosalicylate (ZIS) as a... more The present study explored the feasibility of using zirconium(IV) iodosulphosalicylate (ZIS) as adsorbent for the removal of lead(II) under different conditions. Batch studies were performed to evaluate the influence of various experimental parameters such as pH 7.5, adsorbent dose 200 mg or 10 g L −1 of solution and equilibrium time 120 min for the concentration range of 53.87-241.45 ppm at 323 K. A comparison of kinetic models applied to the adsorption of Pb (II) on ZIS was evaluated for the Lagergren pseudo first order, Ho and McKay pseudo second order, Elovich and intraparticle diffusion kinetic models. The experimental data fitted very well in pseudo second order followed by Elovich model. Intraparticle diffusion does not seem to control the Pb (II) removal process. Equilibrium isotherm for the adsorption of Pb (II) on ZIS was analyzed by Freundlich, Langmuir, Dubnin-Radushkevich (D-R) and Temkin isotherm model using linear regression technique. Langmuir and Freundlich isotherms were found to best represent the data for Pb (II) onto ZIS. The maximum adsorption capacity of ZIS is found to be 327.87 mg g −1 Pb (II). The results show that the sorption capacity increases with increase in temperature, concentration, pH but decreased with adsorbent dose. The thermodynamics parameters such as enthalpy change ( H • = 6797.23 J mol −1 ), entropy change ( S • = 29.333 J mol −1 ), Gibb's free energy ( G • = −2677.45 J mol −1 ) and activation energy (E a = 8198.6 J mol −1 ) results indicate that adsorption process was spontaneous, endothermic nature, increased randomness and shows feasibility and good affinity of Pb (II) toward the adsorbent.
In the present study, various samples of zirconium(IV) phosphosulphosalicylate ion-exchanger were... more In the present study, various samples of zirconium(IV) phosphosulphosalicylate ion-exchanger were synthesized under varying conditions. The sample which showed maximum ion-exchange capacity was selected for further studies. The material has been characterized on the basis of chemical composition, FTIR, X-ray diffraction and TGA studies. To know the practical applicability of the material, distribution coefficient (K d ) values for some metal ions have been evaluated in demineralized water, different concentrations of HNO 3 , 0.1 M thiourea and thiourea-HNO 3 solvent systems. The material has high selectivity for Pb(II). Adsorption kinetic study revealed that the adsorption process followed second order kinetics. G values for the adsorption of Pb(II), Cu(II) and Zn(II) were found to be negative, indicating the adsorption process is spontaneous. On the basis of difference in K d values, some binary separations have also been achieved. The removal efficiency of Pb(II) from a synthetic mixture of metal ions such as Ca(II), Mg(II), Sr(II), Ba(II), Ni(II), Cd(II), Fe(III), Cu(II), Zn(II), Al(III) and Mn(II) has been demonstrated.
Zirconium(IV) iodosulphosalicylate (ZIS), a cation exchanger, was synthesized by mixing 0.1 M zir... more Zirconium(IV) iodosulphosalicylate (ZIS), a cation exchanger, was synthesized by mixing 0.1 M zirconium oxychloride to a mixture of 0.1 M 5-sulphosalicylic acid and 0.1 M potassium iodate at pH 1. The distribution coefficient values of various metal ions were determined at pH 6 which showed high selectivity for Pb(II) ion. Due to its Pb(II) selective nature, the ion-exchanger was used as an electroactive material for the preparation of an ion-selective membrane electrode. The membrane (M − 1) was characterized by XRD and SEM analysis. It was observed that membrane (M − 1) displayed a useful analytical response with excellent reproducibility, low detection limit (4 07 × 10 −6 M), wide working pH range (3-6.5) and quick response time (15 s). The electrode responds to Pb(II) in a linear range from 1 × 10 −5 -1 × 10 −1 M with Nerstian slope of 24 mV per decade change in concentration. The life span of electrode was found to be 90 days. The sensor has been used as indicator electrode in potentiometric titration of Pb(II) ion with EDTA.
The photochemical behavior of the phototoxic antidepressant drug venlafaxine (VLF, 1) was studied... more The photochemical behavior of the phototoxic antidepressant drug venlafaxine (VLF, 1) was studied under aerobic conditions in UV-A light. Irradiation of a phosphate buffer solution of the drug produces N-Demethylated (2) and O-Demethylated (3) as two major photoproducts. The formation of photoproducts (2) and (3) occurs through a singlet oxygen-mediated mechanism, i.e., type-II photodynamic action, involving an irreversible trapping of the self-photogenerated singlet molecular oxygen (1 O 2) and through free radical-mediated mechanism, i.e., type 1 photodynamic action, respectively. The generation of singlet oxygen and free radicals during photolysis was confirmed by singlet oxygen scavenger sodium azide (NaN 3) and free radical scavenger reduced glutathione (GSH). In addition, the comparative antioxidant potentials of the parent drug and its photoproducts were examined utilizing in-silico molecular docking against tyrosinase to better understand the in vivo relevance of drug pharmacological action as a result of drug-light interaction. Photoproduct (2) exhibited less activity as compared to the parent drug, VLF (1), whereas photoproduct (3) formed a stable protein-ligand complex. In order to determine the nature of stability of complex between protein and ligand, further, molecular dynamics (MD) simulation on photoproduct (3) was performed for 100 ns, and the results were analyzed by monitoring root mean square deviations (RMSD), the radius of gyration (Rg), and solvent accessible surface area (SASA). The results proved the formation of a better protein-ligand complex with photoproduct (3). These findings imply that drug users should avoid their exposure to light (natural or artificial) to prevent drug-induced photosensitivity. This study also opens new vistas for the development of novel drugs with desired tyrosinase binding affinity, improved biological features, and low phototoxic manifestations.
He has published 12 research papers in the areas of hybrid naocomposite materials, adsorption, po... more He has published 12 research papers in the areas of hybrid naocomposite materials, adsorption, polymer and potentiometric sensors in refereed international journals and 3 Book Chapters. He has presented several research papers at various national and international conferences. His areas of research include preparation, characterization and application of hybrid nano-composite materials, Thermodynamic and kinetics study of composite material, synthesis of potentiometric sensors for determination of toxic metals in water and their removal, Purification of water using synthesized nano-composite.
Due to its distinct and unique surface morphology, mechanical strength, tunable solubility in wat... more Due to its distinct and unique surface morphology, mechanical strength, tunable solubility in water, viscous properties, ease of access and enormous amount of raw materials, low-cost synthesis process and similarly several more opposing characteristics, carboxymethyl cellulose (CMC) based materials have wide applications. While synthesizing nanoparticles, CMC appears to be better as both a reducing and stabilizing agent. CMC would have no detrimental effects on human health or the environment and also is non-toxic and biodegradable. Hence, CMC mediated metal and metal oxide nanoparticles have multiple benefits in the areas of antibacterial, antimicrobial, antidiabetic, anti-inflammatory, wound healing, antioxidant, as well as optical properties. In this mini-review article, the role of carboxymethyl cellulose (CMC) is highligted in the fabrication of nanoparticles.
The present work describes the synthesis of copper oxide nanoparticles (CuONPs) via a solution pr... more The present work describes the synthesis of copper oxide nanoparticles (CuONPs) via a solution process with the aim of applying the nano-adsorbent for the reduction of methylene blue (MB) dye in alkaline media. These NPs were characterized via Field emission scanning electron microscopy (FE-SEM), X-ray diffraction, high-resolution Transmission electron microscopy (TEM), and ultra violet UV-visible spectroscopy to confirm their morphology and crystalline and optical properties in order to design an adsorption-degradation process. The photocatalytic CuONPs exhibited dynamic properties, great adsorption affinity during the chemisorption process, and operated at various modes with a strong interaction between the adsorbent and the adsorptive species, and equilibrium isotherm, kinetic isotherm, and thermodynamic activities in the presence of UV light. All basic quantities, such as concentration, pH, adsorbent dose, time, and temperature, were determined by an optimization process. The be...
Poly o-toluidine zirconium(IV) iodosulfosalicylate (PTZIS) is a hybrid inorganic–organic composit... more Poly o-toluidine zirconium(IV) iodosulfosalicylate (PTZIS) is a hybrid inorganic–organic composite cation exchanger, which was synthesized by mixing an organic compound, poly o-toluidine, into the matrices of zirconium(IV) iodosulfosalicylate. On the basis of distribution coefficient, Kd, the material was found to have high affinity for adsorption of Cr(III) ion. Due to its Cr(III) selective nature, ion exchanger was used as an electroactive material for preparation of an ion-selective membrane electrode. The physical properties of membrane were determined by XRD, SEM, and AFM analysis, which indicates that PVC-based Cr(III) ion-selective membrane is amorphous and porous in nature. The electrode responds to Cr(III) in a linear range from 3.16 × 10–6 to 1 × 10–1 M with a Nernstian slope of 22 ± 0.5 mV per decade change in concentration and a detection limit of 1.584 × 10–6 M. The life span of the electrode is found to be 12 weeks. The proposed electrode shows satisfactory performance over a pH range of 3.0...
ABSTRACT The present study explored the feasibility of using zirconium(IV) iodosulphosalicylate (... more ABSTRACT The present study explored the feasibility of using zirconium(IV) iodosulphosalicylate (ZIS) as adsorbent for the removal of lead(II) under different conditions. Batch studies were performed to evaluate the influence of various experimental parameters such as pH 7.5, adsorbent dose 200 mg or 10 g L−1 of solution and equilibrium time 120 min for the concentration range of 53.87–241.45 ppm at 323 K. A comparison of kinetic models applied to the adsorption of Pb (II) on ZIS was evaluated for the Lagergren pseudo first order, Ho and McKay pseudo second order, Elovich and intraparticle diffusion kinetic models. The experimental data fitted very well in pseudo second order followed by Elovich model. Intraparticle diffusion does not seem to control the Pb (II) removal process. Equilibrium isotherm for the adsorption of Pb (II) on ZIS was analyzed by Freundlich, Langmuir, Dubnin–Radushkevich (D–R) and Temkin isotherm model using linear regression technique. Langmuir and Freundlich isotherms were found to best represent the data for Pb (II) onto ZIS. The maximum adsorption capacity of ZIS is found to be 327.87 mg g−1 Pb (II). The results show that the sorption capacity increases with increase in temperature, concentration, pH but decreased with adsorbent dose. The thermodynamics parameters such as enthalpy change (ΔH° = 6797.23 J mol−1), entropy change (ΔS° = 29.333 J mol−1), Gibb's free energy (ΔG° = −2677.45 J mol−1) and activation energy (Ea = 8198.6 J mol−1) results indicate that adsorption process was spontaneous, endothermic nature, increased randomness and shows feasibility and good affinity of Pb (II) toward the adsorbent.
Zirconium(IV) phosphosulphosalicylate, a cation exchanger was synthesized by mixing zirconium oxy... more Zirconium(IV) phosphosulphosalicylate, a cation exchanger was synthesized by mixing zirconium oxychloride to a mixture of 5-sulphosalicylic acid and phosphoric acid. The material showed good efficiency for the preparation of an ion-selective membrane electrode. The membrane was characterized affinity for Pb(II) ions. Due to its Pb(II) selective nature, the ion-exchanger was used as an electroactive by XRD and SEM analysis. The electrode responds to Pb(II) ions in a linear range from 1 • 10 À5 to 1 • 10 À1 M with a slope of 43.8 mV per decade change in concentration with detection limit of 4.78 • 10 À6 M. The life span of electrode was found to be 90 days. The proposed electrode showed satisfactory performance over a pH range of 4.0-6.5, with a fast response time of 15 s. The sensor has been applied to the determination of Pb(II) ions in water samples of different origins. It has also been used as indicator electrode in potentiometric titration of Pb(II) ion with EDTA.
ABSTRACT The UV–visible spectrophotometric method has been described the study of raw carbon nano... more ABSTRACT The UV–visible spectrophotometric method has been described the study of raw carbon nanotubes (R-MWCNTs) and functionalized multiwall carbon nanotubes (F-MWCNTs) for the control of bacterial growth by using validated analytical techniques. The absorption spectra of functionalized carbon nanotubes (F-MWCNTs) and raw carbon nanotubes (R-MWCNTs) show maximum absorbance at λ max 600 nm. The linear relationship was found between absorbance and concentration of R-MWCNTs and F-MWCNTs in the range of 0.25–2.0 μg mL−1. The linear regression equation was evaluated by statistical treatment of calibration data and gives the value of correlation coefficient for F-MWCNTs (0.9999) and R-MWCNTs (0.9993), which indicate excellent linearity. The Optical and regression characteristics of the proposed method were found apparent molar absorptivity, limits of detection (LOD), and limit of quantitation (LOQ) for R-MWCNTs and F-MWCNTs (5.75 × 102: 8.25 × 102 L mol−1 cm−1), (0.052: 0.018 μg mL−1), and (0.055: 0.158 μg mL−1), respectively. The validity of the proposed method was checked by precision, accuracy, linearity, limits of detection (LOD), and limit of quantitation (LOQ). The RSD (%) and quantitative recoveries (%) were obtained (0.026–0.0086) and (100.34 and 100.71) for R-MWCNTs: for F-MWCNTs by UV–visible spectrophotometric, respectively.
The present work describes the synthesis of copper oxide nanoparticles (CuONPs) via a solution pr... more The present work describes the synthesis of copper oxide nanoparticles (CuONPs) via a solution process with the aim of applying the nano-adsorbent for the reduction of methylene blue (MB) dye in alkaline media. These NPs were characterized via Field emission scanning electron microscopy (FE-SEM), X-ray diffraction, high-resolution Transmission electron microscopy (TEM), and ultra violet UV-visible spectroscopy to confirm their morphology and crystalline and optical properties in order to design an adsorption-degradation process. The photocatalytic CuONPs exhibited dynamic properties, great adsorption affinity during the chemisorption process, and operated at various modes with a strong interaction between the adsorbent and the adsorptive species, and equilibrium isotherm, kinetic isotherm, and thermodynamic activities in the presence of UV light. All basic quantities, such as concentration, pH, adsorbent dose, time, and temperature, were determined by an optimization process. The best-fitted adsorption Langmuir model (R 2 = 0.9988) and performance, including adsorption capacity (350.87 mg/g), photocatalytic efficiency (90.74%), and degradation rate constant (Ks = 2.23 ×10 −2 min −1), illustrate good feasibility with respect to sorption-reduction reactions but followed a pseudo-second-order kinetic on the adsorbent surface, reaching an equilibrium point in 80 min. The thermodynamic analysis suggests that the adsorption reaction is spontaneous and endothermic in nature. The thermodynamic parameters such as enthalpy (∆H°), entropy (∆S°), and Gibbs free energy (∆G°) give effective results to support a chemical reduction reaction at 303 K temperature. The equilibrium isotherm and kinetic and thermodynamic models with error function analysis explore the potential, acceptability, accuracy, access to adsorbents, and novelty of an unrivaled-sorption system.
Poly o-toluidine zirconium(IV) iodosulfosalicylate (PTZIS) is a hybrid inorganic−organic composit... more Poly o-toluidine zirconium(IV) iodosulfosalicylate (PTZIS) is a hybrid inorganic−organic composite cation exchanger, which was synthesized by mixing an organic compound, poly o-toluidine, into the matrices of zirconium(IV) iodosulfosalicylate. On the basis of distribution coefficient, K d , the material was found to have high affinity for adsorption of Cr(III) ion. Due to its Cr(III) selective nature, ion exchanger was used as an electroactive material for preparation of an ionselective membrane electrode. The physical properties of membrane were determined by XRD, SEM, and AFM analysis, which indicates that PVC-based Cr(III) ion-selective membrane is amorphous and porous in nature. The electrode responds to Cr(III) in a linear range from 3.16 × 10 −6 to 1 × 10 −1 M with a Nernstian slope of 22 ± 0.5 mV per decade change in concentration and a detection limit of 1.584 × 10 −6 M. The life span of the electrode is found to be 12 weeks. The proposed electrode shows satisfactory performance over a pH range of 3.0−7.0, with a fast response time of 10s. The sensor has been applied to determination of Cr(III) ions in water samples of different origins. The sensor has been used as an indicator electrode in potentiometric titrations of Cr(III) ion with EDTA.
Various samples of zirconium(IV) iodosulphosalicylate have been synthesized under varying mixing ... more Various samples of zirconium(IV) iodosulphosalicylate have been synthesized under varying mixing ratios of aqueous solutions of 0.1 M zirconium oxychloride, 0.1 M potassium iodate and 0.1 M 5-sulphosalicylaic acid at pH 1. The material showed ion-exchange capacity of 1.58 meqg −1 for K + . pH titration curve indicated its monofunctional behavior. On the basis of chemical composition, FTIR and thermogravimetric analysis the tentative formula was proposed as (ZrO) 2 (HIO 3 )(C 6 H 3 COOH · OH · SO 3 H)(OH) 4 · nH 2 O. The distribution coefficient values of 15 metal ions have been determined in distilled water and different concentrations of HNO 3 . The material is highly selective for Pb(II). The adsorption behavior of Pb(II), Th(IV), Al(III) and Cu(II) on the material was studied. Negative values of G at all temperatures (293, 303 and 313 K) indicated the feasibility and spontaneity of the adsorption process. Positive values of S confirmed the randomness of the adsorption process. The removal efficiency of Pb(II) from a synthetic mixture of metal ions such as Mg(II), Ca(II), Sr(II), Ba(II), Cd(II), Mn(II), Zn(II), Co(II), Cu(II), Fe(III), Al(III) and Ni(II) has been demonstrated.
Poly-o-toluidine zirconium(IV) iodosulphosalicylate Ion-exchange capacity Cr(III) selectivity Pse... more Poly-o-toluidine zirconium(IV) iodosulphosalicylate Ion-exchange capacity Cr(III) selectivity Pseudo first order kinetic model Particle diffusion controlled A B S T R A C T An organic-inorganic composite poly-o-toluidine zirconium(IV) iodosulphosalicylate has been synthesized by mixing poly-o-toluidine into the gel of zirconium(IV) iodosulphosalicylate. The physicochemical properties of the material were characterized by FTIR, X-ray, TGA-DTA, SEM, TEM and EDX analysis. The ion-exchange capacity and chemical stability were determined. The adsorption efficiency toward heavy metal ions was determined and material was found to be highly selective for Cr(III). The thermodynamics and kinetics of the sorption of Cr(III) were studied. Adsorption of Cr(III) was explained by pseudo-first order kinetic model. The analytical utility of the material was demonstrated by achieving separation of Cr(III) from other metal ions.
Zirconium(IV) phosphosulphosalicylate, a cation exchanger was synthesized by mixing zirconium oxy... more Zirconium(IV) phosphosulphosalicylate, a cation exchanger was synthesized by mixing zirconium oxychloride to a mixture of 5-sulphosalicylic acid and phosphoric acid. The material showed good efficiency for the preparation of an ion-selective membrane electrode. The membrane was characterized affinity for Pb(II) ions. Due to its Pb(II) selective nature, the ion-exchanger was used as an electroactive by XRD and SEM analysis. The electrode responds to Pb(II) ions in a linear range from 1 · 10 À5 to 1 · 10 À1 M with a slope of 43.8 mV per decade change in concentration with detection limit of 4.78 · 10 À6 M. The life span of electrode was found to be 90 days. The proposed electrode showed satisfactory performance over a pH range of 4.0-6.5, with a fast response time of 15 s. The sensor has been applied to the determination of Pb(II) ions in water samples of different origins. It has also been used as indicator electrode in potentiometric titration of Pb(II) ion with EDTA. ª 2015 The Authors. Production and hosting by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
The present study explored the feasibility of using zirconium(IV) iodosulphosalicylate (ZIS) as a... more The present study explored the feasibility of using zirconium(IV) iodosulphosalicylate (ZIS) as adsorbent for the removal of lead(II) under different conditions. Batch studies were performed to evaluate the influence of various experimental parameters such as pH 7.5, adsorbent dose 200 mg or 10 g L −1 of solution and equilibrium time 120 min for the concentration range of 53.87-241.45 ppm at 323 K. A comparison of kinetic models applied to the adsorption of Pb (II) on ZIS was evaluated for the Lagergren pseudo first order, Ho and McKay pseudo second order, Elovich and intraparticle diffusion kinetic models. The experimental data fitted very well in pseudo second order followed by Elovich model. Intraparticle diffusion does not seem to control the Pb (II) removal process. Equilibrium isotherm for the adsorption of Pb (II) on ZIS was analyzed by Freundlich, Langmuir, Dubnin-Radushkevich (D-R) and Temkin isotherm model using linear regression technique. Langmuir and Freundlich isotherms were found to best represent the data for Pb (II) onto ZIS. The maximum adsorption capacity of ZIS is found to be 327.87 mg g −1 Pb (II). The results show that the sorption capacity increases with increase in temperature, concentration, pH but decreased with adsorbent dose. The thermodynamics parameters such as enthalpy change ( H • = 6797.23 J mol −1 ), entropy change ( S • = 29.333 J mol −1 ), Gibb's free energy ( G • = −2677.45 J mol −1 ) and activation energy (E a = 8198.6 J mol −1 ) results indicate that adsorption process was spontaneous, endothermic nature, increased randomness and shows feasibility and good affinity of Pb (II) toward the adsorbent.
In the present study, various samples of zirconium(IV) phosphosulphosalicylate ion-exchanger were... more In the present study, various samples of zirconium(IV) phosphosulphosalicylate ion-exchanger were synthesized under varying conditions. The sample which showed maximum ion-exchange capacity was selected for further studies. The material has been characterized on the basis of chemical composition, FTIR, X-ray diffraction and TGA studies. To know the practical applicability of the material, distribution coefficient (K d ) values for some metal ions have been evaluated in demineralized water, different concentrations of HNO 3 , 0.1 M thiourea and thiourea-HNO 3 solvent systems. The material has high selectivity for Pb(II). Adsorption kinetic study revealed that the adsorption process followed second order kinetics. G values for the adsorption of Pb(II), Cu(II) and Zn(II) were found to be negative, indicating the adsorption process is spontaneous. On the basis of difference in K d values, some binary separations have also been achieved. The removal efficiency of Pb(II) from a synthetic mixture of metal ions such as Ca(II), Mg(II), Sr(II), Ba(II), Ni(II), Cd(II), Fe(III), Cu(II), Zn(II), Al(III) and Mn(II) has been demonstrated.
Zirconium(IV) iodosulphosalicylate (ZIS), a cation exchanger, was synthesized by mixing 0.1 M zir... more Zirconium(IV) iodosulphosalicylate (ZIS), a cation exchanger, was synthesized by mixing 0.1 M zirconium oxychloride to a mixture of 0.1 M 5-sulphosalicylic acid and 0.1 M potassium iodate at pH 1. The distribution coefficient values of various metal ions were determined at pH 6 which showed high selectivity for Pb(II) ion. Due to its Pb(II) selective nature, the ion-exchanger was used as an electroactive material for the preparation of an ion-selective membrane electrode. The membrane (M − 1) was characterized by XRD and SEM analysis. It was observed that membrane (M − 1) displayed a useful analytical response with excellent reproducibility, low detection limit (4 07 × 10 −6 M), wide working pH range (3-6.5) and quick response time (15 s). The electrode responds to Pb(II) in a linear range from 1 × 10 −5 -1 × 10 −1 M with Nerstian slope of 24 mV per decade change in concentration. The life span of electrode was found to be 90 days. The sensor has been used as indicator electrode in potentiometric titration of Pb(II) ion with EDTA.
The science of polymer chemistry has shown excellent at
creating a broad variety of polymeric ma... more The science of polymer chemistry has shown excellent at creating a broad variety of polymeric materials suitable for a wide range of uses. The molecular architecture of such substances is stunning, but the human eye cannot see atoms, thus it frequently goes unrecognized. To address this issue and provide a window into the physical and mechanical features of these complex systems, molecular modelling is a useful tool. Contrasting the modelling often used in the pharmaceutical sector is the field of polymer modelling. Protein homology modelling, protein-ligand docking, and computer design of combinatorial libraries are all typical in the pharmaceutical modelling industry nowadays due to the enormous resources required to bring a novel medication to market. This is intriguing because whereas synthetic polymers typically consist of a few monomers, the average protein is a polymer of up to 20 monomers (amino acids). Therefore, synthetic polymer modelling should be theoretically easier than protein modelling, yet its applications have received less attention. The computational screening of new prospective polymers may be carried out before synthesis to check for desired characteristics, due to the fast development of polymer modelling to the point where the modelling is quicker than the synthesis
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creating a broad variety of polymeric materials suitable for
a wide range of uses. The molecular architecture of such
substances is stunning, but the human eye cannot see
atoms, thus it frequently goes unrecognized. To address
this issue and provide a window into the physical and
mechanical features of these complex systems, molecular
modelling is a useful tool.
Contrasting the modelling often used in the
pharmaceutical sector is the field of polymer modelling.
Protein homology modelling, protein-ligand docking, and
computer design of combinatorial libraries are all typical
in the pharmaceutical modelling industry nowadays due
to the enormous resources required to bring a novel
medication to market. This is intriguing because whereas
synthetic polymers typically consist of a few monomers,
the average protein is a polymer of up to 20 monomers
(amino acids).
Therefore, synthetic polymer modelling should be
theoretically easier than protein modelling, yet its
applications have received less attention. The
computational screening of new prospective polymers
may be carried out before synthesis to check for desired
characteristics, due to the fast development of polymer
modelling to the point where the modelling is quicker than the synthesis