Nazaran P, Bosio V, Jaeger W, Anghel D F, Klitzing R V
Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin, Strasse des 17. Juni 124, D-10623 Berlin.
J Phys Chem B. 2007 Jul 26;111(29):8572-81. doi: 10.1021/jp068768e. Epub 2007 Apr 27.
In this work, the lateral mobility of polyelectrolyte multilayers was investigated by means of the fluorescence recovery after photobleaching (FRAP) technique, with special attention to the effect of relevant parameters during and after preparation. Different polyelectrolytes with respect to charge density, stiffness, and hydrophilicity were compared. From the experimental results emerged that the density of charged sites along the polymer is the most important parameter controlling the formation of polymer complexes. At higher charge density, more complexes are formed, and the diffusion coefficient decreases. It was observed that the intrinsic backbone stiffness reduces the interpenetration of polyelectrolyte layers and the formation of complexes promoting the lateral mobility. In addition, the lateral mobility increases with increasing ionic strength and with decreasing hydration shell of the added anion in the polyelectrolyte solution. The effect of heating or annealing in electrolyte solution after preparation was also investigated along with the embedding of the probing layer at controlled distances to the multilayer surface.
在这项工作中，通过光漂白后荧光恢复（FRAP）技术研究了聚电解质多层膜的横向迁移率，并特别关注制备过程中和制备后的相关参数的影响。比较了具有不同电荷密度、刚度和亲水性的聚电解质。从实验结果可以看出，聚合物上带电位点的密度是控制聚合物复合物形成的最重要参数。在较高的电荷密度下，会形成更多的复合物，扩散系数降低。据观察，内在的主链刚度会减少聚电解质层的相互渗透以及促进横向迁移率的复合物的形成。此外，横向迁移率随着离子强度的增加以及聚电解质溶液中添加阴离子的水合壳层的减小而增加。还研究了制备后在电解质溶液中加热或退火的影响，以及探测层在距多层膜表面可控距离处的嵌入情况。
