表面活性剂在水溶液中性质的质子核磁共振研究

综述了质子核磁共振的几种方法在表面活性剂水溶液研究中的应用.自从上世纪六十年代以来的许多研究表明核磁共振的各种技术是研究表面活性剂溶液的有效手段.它可以提供表面活性剂在水溶液中的cmc、胶束的结构、尺寸、水化、加溶性质和位置，不同表面活性剂胶束之间的相互作用，以及胶束与生物分子和高聚物的相互作用.化学位移已经成为惯常方法，弛豫测量提供动态信息，自扩散系数测量是研究胶束尺寸的很好手段.近来由于核磁共振技术的不断发展，用于研究生物大分子的2D NOESY和HOESY也逐渐应用到研究表面活性剂聚集结构中.由此可以得到有关表面活性剂在水溶液中行为的分子水平信息，是其它谱学方法所不能及的.

1H NMR Studies of Surfactants in Aqueous Solutions

Surfactant is a substance that lowers the surface tension of the medium in which it is dissolved. They form oriented colloidal aggregates, micelles,when a specific concentration is exceeded and abrupt changes in physical properties of the solution will be observed. Surfactant systems have been proved to bevery useful in many biological and industrial processes. Properties of these systems have been intensively investigated by many spectroscopy methods, especially proton nuclear magnetic resonance (1H NMR). It has played more and more important role in the continued development of NMR new techniques. Characterization of micellization processes, physical properties of micelles, e.g. structure, sizeand shape, hydration of micelles, solubilization by micelles, interaction between micelles of different kinds of surfactants, and that with biological compounds and with polymers were studied by the existing sophisticated NMR techniques. These investigations demonstrate that NMR spectroscopy is a versatile technique for the study of surfactants. It provides information at a molecular level that is not available by other spectroscopic methods. Chemical shift changes, relaxation experiments and NMR self diffusion measurements are almost used routinely. The use of two dimensional NMR spectroscopy, 2D NOESY and HOESY is a growing trend in studying the chain packing in micelles as well as interactions between micelles with other molecules, biological and polymeric. These methods provide a deeper insight into the relative arrangement of surfactant molecules in an associated assembly.