Soares David M, Gomes Wyllerson E, Tenan Mario A
Instituto de Física, Universidade Estadual de Campinas, Campinas SP, Brazil.
Langmuir. 2007 Apr 10;23(8):4383-8. doi: 10.1021/la063508+. Epub 2007 Mar 10.
Self-assembled aggregates of amphiphilic surfactant molecules formed on solid surfaces are similar to biological membranes. To understand the formation mechanism of these aggregates, we have studied the formation of self-organized monolayers from low-concentration sodium dodecyl sulfate (SDS) aqueous solutions (concentration below the critical micelle concentration) on gold surfaces. The study has been carried out by using simultaneously quartz crystal microbalance (QCM) and open circuit potential measurements in situ. We have developed a model which explains the variation of the QCM frequency and open circuit potential following SDS additions to water. The dominant growth mechanism during the major part of film formation was demonstrated to be surface diffusion of surfactant molecules.
两亲性表面活性剂分子在固体表面形成的自组装聚集体类似于生物膜。为了理解这些聚集体的形成机制，我们研究了在金表面由低浓度十二烷基硫酸钠（SDS）水溶液（浓度低于临界胶束浓度）形成自组织单分子层的过程。该研究通过同时原位使用石英晶体微天平（QCM）和开路电位测量来进行。我们开发了一个模型，该模型解释了向水中添加SDS后QCM频率和开路电位的变化。结果表明，在膜形成的主要阶段，主要的生长机制是表面活性剂分子的表面扩散。
