Tabony J, Perly B
CEA-IRDI-DESICP-Département de Physico-Chimie, Centre d'Etudes Nucléaires de Saclay, Gif sur Yvette, France.
Biochim Biophys Acta. 1991 Mar 18;1063(1):67-72. doi: 10.1016/0005-2736(91)90354-b.
Quasielastic incoherent neutron scattering has been used to investigate the rate of local translational diffusion of lipid molecules in phospholipid bilayers of dipalmitoyl-phosphatidylcholine. The measured translational diffusion constants (4 x 10(-10) m2 s-1 at 63 degrees C and 1.4 x 10(-11) m2 s-1 at 30 degrees C) are considerably faster than those deduced using other less direct methods, but are in agreement with those measured in soap-water lyotropic liquid crystals, and with calculated values. This disagreement is attributed to differences in the time and distance scales characterising the various measurements. Quasielastic neutron scattering experiments observe fast motions over molecular distances, whereas other methods tend to measure a rate of diffusion which is averaged over macroscopic distances, and may thus contain contributions from long distance slow diffusive motions such as diffusion between the bilayers.
准弹性非相干中子散射已被用于研究二棕榈酰磷脂酰胆碱磷脂双层中脂质分子的局部平移扩散速率。测得的平移扩散常数（63℃时为4×10⁻¹⁰ m² s⁻¹，30℃时为1.4×10⁻¹¹ m² s⁻¹）比使用其他不太直接的方法推导出来的要快得多，但与在皂 - 水溶致液晶中测得的值以及计算值一致。这种差异归因于表征各种测量的时间和距离尺度的不同。准弹性中子散射实验观察的是分子距离上的快速运动，而其他方法倾向于测量在宏观距离上平均的扩散速率，因此可能包含来自长距离缓慢扩散运动（如双层之间的扩散）的贡献。
