The Experts below are selected from a list of 117 Experts worldwide ranked by ideXlab platform
Youssry Y Botros - One of the best experts on this subject based on the ideXlab platform.
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strong and reversible binding of carbon dioxide in a green metal organic framework
Journal of the American Chemical Society, 2011Co-Authors: Jeremiah J Gassensmith, Ronald A Smaldone, Ross S Forgan, Youssry Y Botros, Hiroyasu Furukawa, Omar M Yaghi, Fraser J StoddartAbstract:The efficient capture and storage of gaseous CO2 is a pressing environmental problem. Although porous metal–organic frameworks (MOFs) have been shown to be very effective at adsorbing CO2 selectively by dint of dipole–quadruple interactions and/or ligation to open metal sites, the gas is not usually trapped covalently. Furthermore, the vast majority of these MOFs are fabricated from nonrenewable materials, often in the presence of harmful solvents, most of which are derived from petrochemical sources. Herein we report the highly selective adsorption of CO2 by CD-MOF-2, a recently described green MOF consisting of the renewable Cyclic Oligosaccharide γ-cyclodextrin and RbOH, by what is believed to be reversible carbon fixation involving carbonate formation and decomposition at room temperature. The process was monitored by solid-state 13C NMR spectroscopy as well as colorimetrically after a pH indicator was incorporated into CD-MOF-2 to signal the formation of carbonic acid functions within the nanoporous ...
Resat Apak - One of the best experts on this subject based on the ideXlab platform.
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simultaneous total antioxidant capacity assay of lipophilic and hydrophilic antioxidants in the same acetone water solution containing 2 methyl β cyclodextrin using the cupric reducing antioxidant capacity cuprac method
Analytica Chimica Acta, 2008Co-Authors: Mustafa Özyürek, Kubilay Guclu, Burcu Bektasoglu, Nilay Gungor, Resat ApakAbstract:Abstract Antioxidants are health beneficial compounds that can protect cells from the damage caused by unstable molecules known as reactive oxygen species (ROS). This work reports the capacity assay of both lipophilic and hydrophilic antioxidants simultaneously, by making use of their ‘host–guest’ complexes with methyl-β-cyclodextrin (M-β-CD), a Cyclic Oligosaccharide, in acetonated aqueous medium using the cupric reducing antioxidant capacity (CUPRAC) method. Thus the order of antioxidant potency of various compounds irrespective of their lipophilicity could be established in the same solvent medium. M-β-CD was introduced as the water solubility enhancer for lipophilic antioxidants. Two percent M-β-CD (w/v) in an acetone–H2O (9:1, v/v) mixture was found to sufficiently solubilize β-carotene, lycopene, vitamin E, vitamin C, synthetic antioxidants and other phenolic antioxidants. This assay was validated through linearity, additivity, precision, and recovery. The validation results demonstrate that the CUPRAC assay is reliable and robust. In acetonated aqueous solution of M-β-CD, only CUPRAC and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays were capable of measuring carotenoids together with hydrophilic antioxidants. The CUPRAC antioxidant capacities of a wide range of polyphenolics and flavonoids were experimentally reported in this work as trolox equivalent antioxidant capacity (TEAC) in the CUPRAC assay, and compared to those found by reference methods, ABTS/horseradish peroxidase (HRP)–H2O2 and ferric reducing antioxidant power (FRAP) assays.
Mahendra Nath Roy - One of the best experts on this subject based on the ideXlab platform.
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preparation interaction and spectroscopic characterization of inclusion complex of a Cyclic Oligosaccharide with an antidepressant drug
Journal of Inclusion Phenomena and Macrocyclic Chemistry, 2017Co-Authors: Mitali Kundu, Mahendra Nath RoyAbstract:The study is related to characterise the formation, mechanism behaviour and importance of the complexation between nortriptyline hydrochloride (NTHCL), a class of triCyclic antidepressant (TCA) drug and also having neuroprotective effects, with β-cyclodextrin (β-Cyd) acts as an excellent drug-receptor. The continuous various method (Job plot), UV-spectroscopy, fluorescence measurements and powder XRD have been reported to confirm the inclusion complex with 1:1 stoichiometry with the TCA aliphatic tail. A variant view of NTHCL/β-CD complex where the interaction of triCyclic ringring with β-Cyd cavity is presented in this work using 1HNMR, 13C NMR and FTIR spectroscopy. The most considerable evidence for inclusion of nortriptyline triCyclic ring and the protons located inside the β-Cyd cavity is the 2D NMR ROESY cross-peaks. Changes in chemical shifts in 1H NMR and behaviour of 2D ROESY cross peak suggest the inclusion complex formation. Preparation, mechanism and characterization of the complexation phenomenon for nortriptyline hydrochloride a TCA drug with β-Cyd (a good drug receptor) have been done in solution/solid phase.
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subsistence of inclusion complex via assembly of a drug into Cyclic Oligosaccharide its formation mechanism behaviour and importance
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2017Co-Authors: Mitali Kundu, Mahendra Nath RoyAbstract:The aim of this present work is to make soluble DEPM in aqueous medium through the formation inclusion complex into the hydrophobic hollow space of β-cyclodextrin (β-Cyd) which will provide a novel approach for designing drug delivery system in aqueous medium. The study of supramolecular complexation of DEPM with β-Cyd has been designed in both solution and solid state. In solution phase the evidences of the presence of non-covalent interactions in inclusion complex with 1:1 stoichiometry behaviour are obtained by investigating the UV-spectroscopy. The resultant solid of DEPM and β-Cyd is established by 1H NMR, FTIR, powder XRD and SEM techniques. So, β-Cyd has the ability to encapsulate DEPM into their core without formation any covalent bonds and also increases the bioavailability of the water insoluble DEPM drug.
Fraser J Stoddart - One of the best experts on this subject based on the ideXlab platform.
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strong and reversible binding of carbon dioxide in a green metal organic framework
Journal of the American Chemical Society, 2011Co-Authors: Jeremiah J Gassensmith, Ronald A Smaldone, Ross S Forgan, Youssry Y Botros, Hiroyasu Furukawa, Omar M Yaghi, Fraser J StoddartAbstract:The efficient capture and storage of gaseous CO2 is a pressing environmental problem. Although porous metal–organic frameworks (MOFs) have been shown to be very effective at adsorbing CO2 selectively by dint of dipole–quadruple interactions and/or ligation to open metal sites, the gas is not usually trapped covalently. Furthermore, the vast majority of these MOFs are fabricated from nonrenewable materials, often in the presence of harmful solvents, most of which are derived from petrochemical sources. Herein we report the highly selective adsorption of CO2 by CD-MOF-2, a recently described green MOF consisting of the renewable Cyclic Oligosaccharide γ-cyclodextrin and RbOH, by what is believed to be reversible carbon fixation involving carbonate formation and decomposition at room temperature. The process was monitored by solid-state 13C NMR spectroscopy as well as colorimetrically after a pH indicator was incorporated into CD-MOF-2 to signal the formation of carbonic acid functions within the nanoporous ...
Omar M Yaghi - One of the best experts on this subject based on the ideXlab platform.
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strong and reversible binding of carbon dioxide in a green metal organic framework
Journal of the American Chemical Society, 2011Co-Authors: Jeremiah J Gassensmith, Ronald A Smaldone, Ross S Forgan, Youssry Y Botros, Hiroyasu Furukawa, Omar M Yaghi, Fraser J StoddartAbstract:The efficient capture and storage of gaseous CO2 is a pressing environmental problem. Although porous metal–organic frameworks (MOFs) have been shown to be very effective at adsorbing CO2 selectively by dint of dipole–quadruple interactions and/or ligation to open metal sites, the gas is not usually trapped covalently. Furthermore, the vast majority of these MOFs are fabricated from nonrenewable materials, often in the presence of harmful solvents, most of which are derived from petrochemical sources. Herein we report the highly selective adsorption of CO2 by CD-MOF-2, a recently described green MOF consisting of the renewable Cyclic Oligosaccharide γ-cyclodextrin and RbOH, by what is believed to be reversible carbon fixation involving carbonate formation and decomposition at room temperature. The process was monitored by solid-state 13C NMR spectroscopy as well as colorimetrically after a pH indicator was incorporated into CD-MOF-2 to signal the formation of carbonic acid functions within the nanoporous ...
