The elastic and viscous properties of self-assembled amphiphilic membranes dictate the intricate hierarchy of their structure and dynamics ranging from the diffusion of individual molecules to the large-scale deformation of the membrane. We previously demonstrated that neutron spin echo spectroscopy measurements of model amphiphilic membranes can access the naturally occurring submicrosecond membrane motions, such as bending and thickness fluctuations. Here we show how the experimentally measured fluctuation parameters can be used to determine the inherent membrane properties and demonstrate how membrane viscosity and compressibility modulus are influenced by lipid composition in a series of simple phosphatidylcholine bilayers with different tail lengths as a function of temperature. This approach highlights the interdependence of the bilayer elastic and viscous properties and the collective membrane dynamics and opens new avenues to investigating the mechanical properties of more complex and biologically inspired systems.

中文翻译：

---

用中子自旋回波光谱探测磷脂双层的弹性和粘性

自组装两亲性膜的弹性和粘性决定了其结构和动力学的复杂层次，其范围从单个分子的扩散到膜的大规模变形。我们先前证明，模型两亲膜的中子自旋回波光谱测量可以访问自然发生的亚微秒膜运动，例如弯曲和厚度波动。在这里，我们展示了如何通过实验测量的波动参数来确定固有的膜性能，并证明在一系列具有不同尾长的简单磷脂酰胆碱双层膜中，脂质组成如何影响膜的粘度和可压缩模量，并随温度变化。