Cryogenic-electron microscopy (cryo-EM) refers to a group of methods enabling detailed structural analysis of molecular assemblies and complexes suspended in solution at high resolution. These methods are based on ultra-fast cooling of a liquid sample to the state of vitreous ice, providing a quasi-solid sample representing the bulk phase, that can safely be studied at the high vacuum of EMs, and provide detailed, reliable high-resolution structural information. Progress in specimen preparation devices and detection positioned classical cryo-EM methods, direct-imaging cryogenic-transmission electron microscopy (cryo-TEM) and freeze-fracture (FF-TEM), as central techniques for uncovering the structure and morphology of individual complexes, the coexistence of several structures, structural and phase transformations, self-assembly pathways, and growth laws in micellar solutions. Additionally, two new powerful methods emerged in recent years: cryo-tomography, and cryo-SEM. The first method, which is based on recording a series of images at various angles, yields 3D construction of the complexes. The latter method provides topological information and elemental analysis, even of highly concentrated or highly viscous systems.

My talk will emphasize the use of advanced cryo-EM methods in exploring self-assembling systems, especially of soft-materials, as a tool for basic research as well as for drug delivery and nano-technological applications.