Electro and Magnetooptic Studies of Phospholipid Tubules

在适当的温度、浓度和压力条件下，磷脂组织成各种有趣的和潜在有用的结构，包括扁平的片状结构、细长的棒状结构和封闭的囊泡。这些囊泡的尺寸从几百埃到几十微米不等，由水介质分隔的双层组成。美国海军研究实验室/地球中心联合小组最近发现了一种由可聚合二乙基磷脂组成的新结构。39℃以下的双层材料组装成直的空心管，形状类似于一卷铝箔。计划用这些材料进行许多磁学和电光实验。为了更好地了解小管的分子取向，将对稀释的小管悬浮液进行Cotton-Mouton测量。在较高的浓度下，双折射和光散射将用于确定悬浮中小管的粒子间势，包括短程和长距离部分。此外，将尝试定位液晶向列相，如果成功，将与机械性能和可能的非线性光学响应的研究相补充。最后，一些不同的研究将涉及小管操作。

Under appropriate conditions of temperature, concentration and pressure, phospholipids organize into a variety of interesting and potentially useful structures, including flat lamellae, elongated rodlike structures, and closed vesicles. These vesicles range in dimension from hundreds of angstroms to tens of microns and consist of bilayers separated by an aqueous medium. A new structure composed of a polymerizable diacetylenic phospholipid was recently discovered by a joint Naval Research Laboratory/Geo-Centers group. Below 39 C pieces of bilayer assemble into straight, hollow tubules in a form similar to a roll of aluminum foil. A number of magneto-and electrooptic experiments are planned with these materials. Cotton-Mouton measurements will be made on dilute suspensions of tubles in order to better understand the molecular orientation with the tubule. At higher concentrations, birefringence and light scattering will be used to determine the interparticle potential of tubules in suspension, both the short and long range parts. In addition, an attempt will be made to locate a liquid crystal nematic phase which, if successful, will be complemented with studies of the mechanical properties and possible non-linear optical response. Finally, a number of different studies will be made involving tubule manipulation.