Inoue T, Iwanaga T, Fukushima K, Shimozawa R, Suezaki Y
Department of Chemistry, Faculty of Science, Fukuoka University, Japan.
Chem Phys Lipids. 1988 Oct;48(3-4):189-96. doi: 10.1016/0009-3084(88)90089-8.
The interaction of surfactants with the vesicle membrane of the negatively charged lipid, dilauroylphosphatidic acid, was investigated through their effect on the gel-to-liquid-crystalline phase transition of the lipid bilayer. Three types of surfactants (anionic, cationic and non-ionic) with different hydrocarbon chain length were examined. (i) Anionic sodium alkylsulfates affected the phase transition temperature, Tm, only weakly. (ii) Non-ionic alkanoyl-N-methylglucamides decreased Tm monotonously with increasing concentration. The depression of Tm induced by these surfactants was analyzed by applying the van't Hoff model for the freezing-point depression, and the partition coefficients of the surfactants between bulk water and lipid membrane were estimated. (iii) Cationic alkyltrimethylammonium bromides affected Tm in a complex manner depending on the hydrocarbon chain length of the surfactants. Octyl-/tetradecyl-trimethylammonium bromide depressed/elevated Tm monotonously with increasing concentration, whereas the change in Tm induced by decyl- and dodecyltrimethylammonium bromides was not monotonous but biphasic. This complex behavior of the phase transition temperature was well explained, based on the statistical mechanical theory presented by Suezaki et al. (Biochim. Biophys. Acta, 818 (1985) 31-37), which takes into account the interaction between surfactant molecules incorporated in the lipid membrane.
通过表面活性剂对带负电荷脂质二月桂酰磷脂酸的囊泡膜凝胶-液晶相转变的影响，研究了它们之间的相互作用。考察了三种不同烃链长度的表面活性剂（阴离子型、阳离子型和非离子型）。（i）阴离子型烷基硫酸钠对相转变温度Tm的影响较弱。（ii）非离子型链烷酰-N-甲基葡糖酰胺随浓度增加使Tm单调降低。应用范特霍夫冰点降低模型分析了这些表面活性剂引起的Tm降低，并估算了表面活性剂在本体水和脂质膜之间的分配系数。（iii）阳离子型烷基三甲基溴化铵对Tm的影响较为复杂，取决于表面活性剂的烃链长度。随着浓度增加，辛基/十四烷基三甲基溴化铵使Tm单调降低/升高，而癸基和十二烷基三甲基溴化铵引起的Tm变化并非单调而是双相的。基于Suezaki等人提出的统计力学理论（《生物化学与生物物理学报》，818（1985）31-37），考虑了脂质膜中掺入的表面活性剂分子之间的相互作用，很好地解释了相转变温度的这种复杂行为。
