The molecular interaction of inclusion complex between βcyclodextrin(βCD)and nicotine in aqueous solutions was studied by UVVis spectrophotometric and proton nuclear magnetic resonance(1HNMR)spectrosco...The molecular interaction of inclusion complex between βcyclodextrin(βCD)and nicotine in aqueous solutions was studied by UVVis spectrophotometric and proton nuclear magnetic resonance(1HNMR)spectroscopy.It was found that the inclusion complex between βCD and nicotine can also be formed in alkaline aqueous solutions at pH=105.The result can be further proved by a competitive inclusion process using phenolphthalein as a probe.A solid with supermolecular structure of βCD/nicotine was prepared,and its powder Xray diffraction data indicated that the crystalline structure of inclusion complex is different from the original βCD crystalline structure.The result of differential scanning calorimetry(DSC)can also confirm this conclusion.展开更多
Aim：To investigate quantitatively the binding ability and inclusion complexation behavior of curcumin with natural α-，β-，γ-cyclodextrins(1-3) and a series of organoselenium-bridged bit(β-cyclodextrin)s with sim...Aim：To investigate quantitatively the binding ability and inclusion complexation behavior of curcumin with natural α-，β-，γ-cyclodextrins(1-3) and a series of organoselenium-bridged bit(β-cyclodextrin)s with simple spacer (4-6).Methods:The spectrophotometric titrations have been performed in KCl-HCl buffer solutioln(pH=2.0) at 25℃ to calculate the complex stability constants(Ks) and Gibbs free energy changes(ΔG°) for the stoichiometric 1:1 incluon complexation of 1-6 with curcumin.Results:The binding ability of β-cyclodextrin for inclusion complexation with guest curcumin is higher than that of α-and γ-cyclodextrinms.As compared with parent β-cyclodextrin for inclusion complexation with guest curcumin is higher than that of α-and γ-cyclodextrins.As compared with parent β-cyclodextrin by a factor 2.8-17.1,Conclusion:Size/shape fit and hydrophobic interaction between host cyclodextrins and guest curcumin molecule are the important factors affecting the binding ability and inclusion complex ation behavior of these cyclodextrins 1-6.展开更多
文摘The molecular interaction of inclusion complex between βcyclodextrin(βCD)and nicotine in aqueous solutions was studied by UVVis spectrophotometric and proton nuclear magnetic resonance(1HNMR)spectroscopy.It was found that the inclusion complex between βCD and nicotine can also be formed in alkaline aqueous solutions at pH=105.The result can be further proved by a competitive inclusion process using phenolphthalein as a probe.A solid with supermolecular structure of βCD/nicotine was prepared,and its powder Xray diffraction data indicated that the crystalline structure of inclusion complex is different from the original βCD crystalline structure.The result of differential scanning calorimetry(DSC)can also confirm this conclusion.
文摘Aim：To investigate quantitatively the binding ability and inclusion complexation behavior of curcumin with natural α-，β-，γ-cyclodextrins(1-3) and a series of organoselenium-bridged bit(β-cyclodextrin)s with simple spacer (4-6).Methods:The spectrophotometric titrations have been performed in KCl-HCl buffer solutioln(pH=2.0) at 25℃ to calculate the complex stability constants(Ks) and Gibbs free energy changes(ΔG°) for the stoichiometric 1:1 incluon complexation of 1-6 with curcumin.Results:The binding ability of β-cyclodextrin for inclusion complexation with guest curcumin is higher than that of α-and γ-cyclodextrinms.As compared with parent β-cyclodextrin for inclusion complexation with guest curcumin is higher than that of α-and γ-cyclodextrins.As compared with parent β-cyclodextrin by a factor 2.8-17.1,Conclusion:Size/shape fit and hydrophobic interaction between host cyclodextrins and guest curcumin molecule are the important factors affecting the binding ability and inclusion complex ation behavior of these cyclodextrins 1-6.
