【摘要】 叙述了用时间分辨率纳秒荧光技术研究大豆磷脂或合成磷脂模型膜（脂质体）的物理状态变化与荧光寿命以及时间分辨各向异性测量参数变化相关性的实验结果。用荧光探剂ＭＣ５４０（Ｍｅｒｏｃｙａｎｉｎｅ５４０）标记模型膜的结果表明，荧光寿命（τ）的变化与脂质／探剂比例、磷脂组成、磷脂的极性头部、脂肪酸酰链长度等有关。用ＤＰＨ（１，６－ｄｉｐｈｅｎｙｌ－１，３，５－ｈｅｘａｔｒｉｅｎｅ）标记磷脂模型膜的时间分辨各向异性分析结果表明，序参数（Ｓ）、微粘度（η）和旋转相关时间（τｒ）等参数的变化与磷脂的组成及其比例、脂肪酸侧链的长度等有关。并对由稳态荧光测量和瞬态荧光测量结果的相关性进行了讨论。更多还原

【Abstract】 Relationships between the physical state changes of lipids and the fluorescence anisotropyparameters in model membrane (liposomes) made of asolectin or synthetic phospholipidsstudied by nanosecond time-resolved fluorescence spectroscopy are described in the presentstudy.The lifetime (τ, ns) of Merocyanine 540 (MC540) in asolectin liposomes was increased withincreasing ratio of the probe to lipids. Lifetime of the probe also depends on components andnature of phospholipids, especially acidic phopholipid. The lifetime (1.89ns) of MC540 inPE-liposomes was significantly decreased to 1.64ns (for PE/PS, 1: 1) or 1.34ns (for PE/PS,1:6). The same results were obtained for PC or PC/PS liposomes labeled with MC540or DPH.Analysis of the-resolved fluorescence anisotropy of synthetic phospholipid model mem branes labeled by DPH (1, 6-diphenyl-1, 3, 5-hexatriene) indicates that changes ofmicroviscosity (η) and rotational correlation time (τr) were in the order: DPPC<PC<DLPCliposomes; Change of the order parameter (S or P, from the time-resolved or steady-statefluorescence spectroscopy measurements, respectively) were in the older: DLPC<PC<DPPCliposomes indicating fluidity of lipid molecules are in the order: DLPC>PC>DPPC.The results from anisotropy measurement of DPH in PC or PC/PS (1:6) liposomes indicatethat order Parameter (S or P) were obviously wital While τr and η were increased whenliposomes were prepared in the presence of acidic phospholipid, PS. It may show that changesof both the probe’s local environment and lipid bilayer of the membranes can besimultaneously measured by the approach of nanosecond time-resolved fluorescencespectroscopy.更多还原