固态磷脂相变行为的红外和拉曼光谱研究

用红外和拉曼光谱方法在２９０～４０５Ｋ的温度范围内考察了无水二肉豆蔻酰磷脂酰乙醇胺的分子构象随温度的变化。结果表明，该磷脂在３６５Ｋ附近的熔化相变过程中，不仅酰链的构象和堆积发生了有序－无序转变，而且极性头部基团和接界区域基团也发生了结构重排；逆相变过程中，烷基链构象重新恢复了有序，但头部基团和甘油骨架构象没有恢复原始有序状态。

Studies on Phase Transition Behavior of Anhydrous Phospholipid by lnfrared and Raman Spectroscopy

The temperature dependence of the infrared and Raman spectra of anhydrousdimyristoylphosphatidylethanolamine(DMPE ) was investigated in the temperature rangefrom 290 to 405K. The spectra of the C-H,C=Oand PO2stretching mode regions reflectthat a cooperative phase transition occurs at about 365K. During the transition a significantlateral expansion of the lipid bilayer is present and accompanied both by an increased numberof gauche rotamers within the hydrocarbon chain region and by muItiple conformers in boththe head group and glycerol backbone moieties. When the lipids are rapidly cooled,the acylchain region reorders without a concomitant reordering of the head group and interface re-gion.