Microrheology of solutions embedded with thread-like supramolecular structures

A family of methods uses colloidal particles as a mechanical probe for deforming the medium in conjunction with a procedure to trace the movement of the particles to get rheological information in a very wide frequency range. All of them are under the heading of microrheology. In the last decade, they have been developed up to the point of being a useful tool for understanding the structure and the dynamics of solutions with embedded thread-like supramolecular structures. This is the case of wormlike micellar solutions, which is the main interest of the paper. Here the impact of microrheology has been essential, providing structural information not easily obtained by other methods. Microrheology has also made an important contribution to the understanding of other threadlike system, as in the case of F-actin or fd virus solutions; they will also be discussed.