PHASE-DIAGRAM OF SOYBEAN PHOSPHATIDYLCHOLINE-DIACYLGLYCEROL-WATER STUDIED BY X-RAY-DIFFRACTION AND P-31-NMR AND PULSED-FIELD GRADIENT H-1-NMR - EVIDENCE FOR REVERSED MICELLES IN THE CUBIC PHASE
PHASE-DIAGRAM OF SOYBEAN PHOSPHATIDYLCHOLINE-DIACYLGLYCEROL-WATER STUDIED BY X-RAY-DIFFRACTION AND P-31-NMR AND PULSED-FIELD GRADIENT H-1-NMR - EVIDENCE FOR REVERSED MICELLES IN THE CUBIC PHASE
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DOI：
10.1016/s0006-3495(95)80362-0
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发表时间：
1995-05-01
影响因子：
3.4
通讯作者：
LJUSBERGWAHREN, H
中科院分区：
文献类型：
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作者：
ORADD, G;LINDBLOM, G;LJUSBERGWAHREN, H
大豆磷脂酰胆碱，甘油二酯，和水的系统的相平衡已被确定使用的经典方法与X-射线衍射和NMR技术的组合。特别是，已确定的层状，反六方和立方相的相区域的程度。通过脉冲场梯度H-1-NMR，在25和59摄氏度下测定了由大豆磷脂酰胆碱、二酰甘油和重水组成的立方相中所有三种组分的扩散系数，并且还测定了由化学上更明确定义的合成组分组成的相应立方相的扩散系数1，2-二油酰-sn-甘油-3-磷酸胆碱（DOPC）、1，2-二油酰甘油（DOG）、和重水。立方相的相区的扩展似乎没有明显的变化为两个三元系统研究。DOPC在该立方相中的平移扩散系数小一个数量级以上（3 × 10（-13）m（2）s（-1），59 ℃）比DOPC在定向脂双层中的横向扩散系数大（5 × 10（-12）m（2）s（-1），35 ℃），而水和DOG的扩散系数被发现比59 ℃下的DOPC大大约两个数量级。它的结论是，立方相建立了封闭的反胶束根据从以前的X-射线衍射研究的建议。
The phase equilibria of the system soybean phosphatidylcholine, diacylglycerol, and water has been determined using a combination of classical methods together with x-ray diffraction and NMR techniques. In particular, the extent of the phase regions of the lamellar, the reversed hexagonal, and the cubic phases have been determined. By pulsed field gradient H-1-NMR, the diffusion coefficients of all three components in a cubic phase composed of soybean phosphatidylcholine, diacylglycerol, and heavy water have been determined at 25 and 59 degrees C and also for the corresponding cubic phase composed of the chemically more well defined synthetic components 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), 1,2-dioleoylglycerol (DOG), and heavy water. The extension of the phase region of the cubic phase did not seem to change appreciably for the two ternary systems studied. The translational diffusion coefficient of DOPC in this cubic phase is more than an order of magnitude smaller (3 x 10(-13)m(2)s(-1), 59 degrees C) than the lateral diffusion coefficient of DOPC in an oriented lipid bilayer (5 x 10(-12)m(2)s(-1), 35 degrees C), whereas the diffusion coefficients of water and DOG were found to be about two orders of magnitude larger than of DOPC at 59 degrees C. It is concluded that the cubic phase is built up of closed reversed micelles in accordance with the suggestion from previous x-ray diffraction studies.