Imaging and Characterization of Self-Assembled Soft Nanostructures

Abstract

Long-ranged double layer interactions and specific tip penetration through the scanned layers should be considered when atomic force microscopy (AFM) is used to probe soft samples such as surfactants or biological material within liquid media. Therefore, AFM imaging of soft nanostructures requires a careful adjust of the applied force and the scanning velocity. A paramount advantage of this technique is that cells immersed in liquids can be imaged under physiological conditions. On the other hand, confocal Raman microscopy (CRM) allows the realtime monitoring and chemical characterization of compounds also in a noncontact manner. The three-dimensional distribution of substances can be recorded by CRM with high spatial resolution by scanning a tightly focused laser beam over the sample. By combining of these two techniques (AFM and CRM), it is possible to obtain relevant information on formation processes, characteristics and behavior of soft self-assembled nanostructures and of cells on hydrophilic or hydrophobic surfaces under physiological conditions.