Acta Chimica Sinica ›› 2012, Vol. 0 ›› Issue (05): 599-605 .DOI: 10.6023/A1012284 Previous Articles     Next Articles

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胆固醇与磷脂酰乙醇胺/磷脂酰胆碱混合膜的热力学特性及其单层膜形态的AFM 观察

王娟, 常怡光, 孙润广   

  1. 陕西师范大学物理学与信息技术学院 生物物理与生物医学工程实验室 西安 710062
  • 投稿日期:2010-12-28 修回日期:2011-10-10 发布日期:2012-03-17
  • 通讯作者: 孙润广
  • 基金资助:

    国家自然科学基金项目(No. 20772077)和教育部高等学校博士学科点专项科研基金(No. 200807180001)资助项目.

Thermodynamic Study on the Monolayer Mixed with Different Chol-content and PE/PC and the Morphology Observation of the Bilayers

Wang Juan, Chang Yiguang, Sun Runguang   

  1. Laboratory of Biophysics and Biomedicine, College of Physics and Information Technology, Shaanxi Normal University, Xi'an, 710062
  • Received:2010-12-28 Revised:2011-10-10 Published:2012-03-17
  • Supported by:

    Project supported by the National Natural Science Foundation of China (No. 20772077), and Research Fund for the Doctoral Program of Higher Education of China (No. 200807180001).

The effect of different cholesterol (Chol)-content on the mixed monolayer of the phosphatidylethanolamine (PE)/phosphatidylcholine (PC) (1∶1 molar ratio) has been investigated by analyzing the surface pressure-area isotherms. And the thermodynamic behavior of mixed monolayer of Chol and PE/PC (1∶1 molar ratio) has been investigated by calculating and analyzing the excess molecular area and excess Gibbs energy (ΔAex and ΔGex). The results show that Chol accelerated the phase transition and promoted the aggregation of monolayer. When XChol=0.2, 0.6, 0.8, ΔAex and ΔGex displayed negative values, suggesting attractive interaction between molecules. While XChol=0.4, ΔAex and ΔGex displayed positive values at the surface pressure of 15, 20, 25, 30 mN/m, indicating repelling interaction between molecules, promoting the increasing of the entropy. In addition, the deposited Langmuir-Blodgett (LB) monolayers of different ratios were investigated with atomic force microscopy (AFM).

Key words: biomembrane, the LB film technique, excess Gibbs energy, isotherm, atomic force microscopy