物理化学学报 >> 2005, Vol. 21 >> Issue (12): 1415-1418.doi: 10.3866/PKU.WHXB20051218

研究简报 上一篇    下一篇

α-环糊精与季铵盐型双子表面活性剂包结作用的研究

邱晓梅; 李玲; 魏西莲; 尹宝霖; 孙德志   

  1. 聊城大学化学化工学院, 山东 聊城 252059
  • 收稿日期:2005-04-14 修回日期:2005-06-22 发布日期:2005-12-15
  • 通讯作者: 孙德志 E-mail:sundezhisdz@163.com

A Study on Complexation between α-cyclodextrin and Bis-quaternary Ammonium Surfactants

QIU Xiao-Mei; LI Ling; WEI Xi-Lian; YIN Bao-Lin; SUN De-Zhi   

  1. College of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059
  • Received:2005-04-14 Revised:2005-06-22 Published:2005-12-15
  • Contact: SUN De-Zhi E-mail:sundezhisdz@163.com

摘要: 在293.15 K下用微量热法结合核磁共振波谱研究了α-环糊精与三种阳离子型双子表面活性剂((CnN)2Cl2, n=12, 14, 16) 在水溶液中的包结作用. 实验结果表明, 包结物都相当稳定, 且随着疏水链CnH2n+1中碳原子数目的增加, 主-客体包结物的化学计量比由2∶1为主变为6∶1为主, 最大化学计量比的主-客体包结物形成过程的标准焓变(ΔHӨ) 和标准熵变(ΔSӨ) 均为负值且绝对值逐渐增大. 包结物的形成均属焓驱动过程. 1H核磁共振数据表明, (C12H25N)2Cl2的存在使α-环糊精上各质子的化学位移向高场移动, 从微观上证明了包结作用的发生.

关键词: α-环糊精, 阳离子型双子表面活性剂, 微量热, 1H核磁共振, 主-客体包结物

Abstract: The inclusion interaction between α-cyclodextrin (α-CD) with three cationic gemini surfactants, (CnN)2Cl2 (n =12, 14, 16), in aqueous solutions has been investigated by isothermal titration calorimetry, combining with 1H NMR at 293.15 K. The results show that these complexes are quite stable. As the number of carbon atoms in each of the hydrophobic tail, CnH2n+1, increases, the stoichiometry of stable complexes changes from 2∶1 to 6∶1. Corresponding to the same change of the hydrophobic chain, both formation enthalpy and formation entropy evidently decrease. The results also indicate that the association processes are enthalpy driven ones. The data of proton NMR spectroscopy indicate that chemical shift data of all protons in the α-CD molecule move to high field in the presence of the (C12H25N)2Cl2, which can be regarded as a microscopic evidence of the occurrence of inclusion interaction.

Key words: α-cyclodextrin, Cationic gemini surfactants, Isothermal titration calorimeter, Proton NMR spectroscopy, Host-Guest inclusion