Jeworrek Christoph, Steitz Roland, Czeslik Claus, Winter Roland
Physical Chemistry I-Biophysical Chemistry, Technische Universität Dortmund, Dortmund, Germany.
Rev Sci Instrum. 2011 Feb;82(2):025106. doi: 10.1063/1.3553392.
The design of a high pressure (HP) cell for neutron reflectivity experiments is described. The cell can be used to study solid-liquid interfaces under pressures up to 2500 bar (250 MPa). The sample interface is based on a thick silicon block with an area of about 14 cm(2). This area is in contact with the sample solution which has a volume of only 6 cm(3). The sample solution is separated from the pressure transmitting medium, water, by a thin flexible polymer membrane. In addition, the HP cell can be temperature-controlled by a water bath in the range 5-75°C. By using an aluminum alloy as window material, the assembled HP cell provides a neutron transmission as high as 41%. The maximum angle of incidence that can be used in reflectivity experiments is 7.5°. The large accessible pressure range and the low required volume of the sample solution make this HP cell highly suitable for studying pressure-induced structural changes of interfacial proteins, supported lipid membranes, and, in general, biomolecular systems that are available in small quantities, only. To illustrate the performance of the HP cell, we present neutron reflectivity data of a protein adsorbate under high pressure and a lipid film which undergoes several phase transitions upon pressurization.
描述了一种用于中子反射率实验的高压（HP）池的设计。该池可用于研究压力高达2500巴（250兆帕）下的固液界面。样品界面基于一块厚硅块，面积约为14平方厘米。该面积与体积仅为6立方厘米的样品溶液接触。样品溶液通过一层薄的柔性聚合物膜与压力传递介质水隔开。此外，HP池可通过水浴在5-75°C范围内进行温度控制。通过使用铝合金作为窗口材料，组装好的HP池提供高达41%的中子透射率。反射率实验中可使用的最大入射角为7.5°。可达到的大压力范围和所需的少量样品溶液体积使得该HP池非常适合研究压力诱导的界面蛋白质、支撑脂质膜以及一般仅少量可得的生物分子系统的结构变化。为了说明HP池的性能，我们展示了高压下蛋白质吸附物和加压时经历多次相变的脂质膜的中子反射率数据。
