拥挤环境中表面活性剂胶束化过程的低场核磁共振研究

摘要

The aggregation behavior of surfactants in crowding consisted of polyethylene glycol (PEG) was investigated by using low-field nuclear magnetic resonance(LF-NMR). The data of different surfactant - PEG systems obtained from the CPMG sequence's echo peaks and those inversed and fitted revealed that the molecular masses and concentrations of different PEG solutions could be distinguished by using low-field nuclear magnetic resonance. The formation of micelles in PEG solutions with high concentration was observed, but it was not favorable for the observation of the process of micellization in the PEG solutions with low concentration. The existing of NaCl had obvious effect on the ionic surfactants system, but had hardly effect on the nonionic surfactants system. This research enriches the application of LF-NMR technology in the characterization of the process of micellization of surfactants and has a directive significance for understanding the self-assembly behavior and function of molecules in biological systems.%利用长弛豫低场核磁共振(LF-NMR)方法研究了由聚乙二醇(PEG)构建的拥挤溶液环境中表面活性剂的聚集行为.通过Carr-Purcell-Meiboom-Gill (CPMG)脉冲序列所得的回波数据及反演拟合数据对不同的表面活性剂-PEG体系进行分析,结果发现:不同分子量和不同浓度的PEG溶液可用低场核磁共振方法进行区分；高浓度的PEG溶液中均能监测到胶束形成过程,而较低浓度的PEG溶液不利于其胶束化过程监测；NaCl对含有离子型表面活性剂体系的影响较为明显,而对含有非离子型表面活性剂的体系几乎无影响.该研究丰富了低场核磁共振弛豫技术在表面活性剂胶束表征过程中的应用,同时对理解生物体系中分子的自组装及功能也具有重要意义.