华东理工大学学报：自然科学版2012，Vol.38Issue(4)：416-422,7.
Gemini表面活性剂18—3—18与磷脂DPPC在气液界面的混合性质
Interaction between Dipalmitoylphosphatidylcholine and Gemini Surfactant （18-3-18） in Mixed Monolayers at Air-Water Interface
摘要
Abstract
As a non-viral vector in the gene transfection, of which the transfer process is closely associated with cell membrane, Gemini surfactant has become a major focus of research. In this work, the surface pressure-area per molecule （π-A） isotherms of the mixed monolayers of Gemini surfactant （18-3- 18） and dipalmitoylphosphatidylcholine （DPPC） were measured by Langmuir balance, and then the mean molecular area（Am）, excess area of mixed monolayers （△ex）, the excess Gibbs free energy （△Gex）, the Gibbs free energy of mixing （△Gmix） and the interaction parameter a were quantitatively examined. The mixed nature was determined, and the interaction between 18-3-18 and DPPC was further investigated. In addition, the morphologies of the corresponding LB films were observed by AFM. The results indicate that the stability and themodynamics of mixed monolayer of 18 3-18 and DPPC as well as their interactions were affected significantly by the molar ratio of 18-3-18 and DPPC and the surface pressure. In particular, two minima of △G, x and △Gmix for the mixed monolayer of 18-3-18 and DPPC appeared at XDPPC =0. 20 and 0.67, which indicated that the phase separation would occur in the range of 0.20-0.67. This is consistent with the observation by AFM.关键词
Gemini表面活性剂/DPPC/π-A等温线/过量吉布斯自由能/AFMKey words
Gemini surfactant/DPPC/π-A isotherm/surface excess Gibbs energy/AFM分类
化学引用本文复制引用
孙立劝,陈启斌,刘洪来..Gemini表面活性剂18—3—18与磷脂DPPC在气液界面的混合性质[J].华东理工大学学报：自然科学版,2012,38(4):416-422,7.基金项目
国家自然科学基金(20806025) （20806025）
长江学者与创新团队发展计划(IRT0721) （IRT0721）
