Study of Spread Monolayers on Liquid by Polarization Modulation IR External Reflection Spectroscopy

偏振调制红外外反射光谱研究液体上单分子层的铺展

• 批准号: 11440204
• 负责人: UMEMURA Junzo
• 金额: $ 9.47万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11440204/
• 关键词: Polarization Modulation IR Spectroscopy; IR External Reflection Soectroscopy; Zinc Stearate; Zinc 12-Hydroxystearate; Langmuir Monolaver; Surface Pressure Relaxation Process; 展開単分子膜; 偏光変調赤外外部反射スペクトル; ラングミュア膜

In situ polarization modulation FT-IR external reflection spectra of Langmuir monolayers of zinc stearate and zinc 12-hydroxystearate on the water surface were recorded at various surface areas, and their molecular structures were estimated. In the zinc stearate monolayer, the wavenumbers and the absorbances of the antisymmetric and symmetric methylene stretching bands did not change on monolayer compression, which means that the orientational and conformational changes of the hydrocarbon chain did not occur. However, the wavenumber changes of the antisymmetric and symmetric carboxylate stretching bands were observed on surface compression. The change in the binding nature of the zinc cation to the carboxylate group was speculated. Moreover, it was elucidated that the structure of the hydrocarbon chain in the zinc 12-hydroxystearate monolayer was different from that in the zinc stearate monolayer.During the surface pressure relaxation after rapid surface compression, the wavenumber of the antisymmetric CH_2 stretching frequency decreased from 2916 to 2914 cm^<-1>, while the CH_2 scissoring frequency increased from 1470 to 1474 cm^<-1>. In the above semi-static compression, these frequencies coincided with those of the equilibriated values after 30 minutes. The tendency of these frequency shifts during surface relaxation indicate the structural change to more condensed states. On the other hand, the antisymmetric COO^- stretching frequency increased from 1540 to 1543 cm^<-1>. These values correspond to those of the the COO^- group ionically bounded to the Zn^<++> ion. The frequency increase during surface pressure relaxation suggests the increase in the OCO angle.These data provide us with the fundamental information concerning the effect of metal ions on biologically important materials.

记录了硬脂酸锌和12-羟基硬脂酸锌在不同表面积上的Langmuir单层的原位偏振调制FT-IR外反射光谱，并对其分子结构进行了估计。在硬脂酸锌单分子层中，反对称和对称亚甲基拉伸带的波数和吸光度在单分子层压缩时没有发生变化，这意味着烃链的取向和构象没有发生变化。在表面压缩过程中，羧酸盐拉伸带的波数发生了变化。推测了锌阳离子与羧酸基结合性质的变化。此外，还证实了12-羟基硬脂酸锌单分子层中的烃链结构与硬脂酸锌单分子层中的不同。在快速表面压缩后的表面压力松弛过程中，CH_2的反对称拉伸频率波数从2916减小到2914 cm^<-1>， CH_2的剪切频率波数从1470增大到1474 cm^<-1>。在上述半静态压缩中，这些频率与30分钟后的平衡值一致。这些频移在表面弛豫过程中的趋势表明结构向更凝聚态转变。另一方面，反对称COO^-拉伸频率从1540 cm^<-1>增加到1543 cm^<-1>。这些值对应于与Zn^<++>离子结合的COO^-基团的值。表面压力松弛时频率的增加表明OCO角的增加。这些数据为我们提供了有关金属离子对重要生物材料影响的基本信息。

项目成果

H.Sakai, J.Umemura: "Evaluation of molecular structure in Langmuir monolayers of zinc stearate and zinc 12-hydroxystearate by infrared external reflection spectroscopy"Colloid and Polymer Science. 280・4. 316-321 (2002)

H.Sakai、J.Umemura：“通过红外外反射光谱评价硬脂酸锌和 12-羟基硬脂酸锌的 Langmuir 单层分子结构”《胶体与聚合物科学》280・4（2002 年）。

H. Sakai, J. Umemura: "Evaluation of molecular structure in Langmuir monolasers of zinc stearate and zinc 12-hydroxystearate by infrared external reflection spectroscopy"Colloid and Polymer Science. 280-4. 316-321 (2002)

H. Sakai，J. Umemura：“通过红外外反射光谱评估硬脂酸锌和 12-羟基硬脂酸锌的 Langmuir 单激光器分子结构”《胶体与聚合物科学》。