Many of the research groups using the Cypher VRS video-rate AFM and other high-speed AFMs use them to visualize reactions and other dynamics in biomolecular systems. However, many non-biological molecules also exhibit self-assembly processes at solid-liquid interfaces and the structures formed can be highly dynamic in response to mechanical, thermal, and chemical perturbations. Video-rate AFM is therefore a powerful tool for visualizing the self-assembly and subsequent dynamics of these events.
Here we present results demonstrating how the Cypher VRS was used to study the dynamics of self-assembled surfactant micelles at a solid-liquid interface. A solution of the surfactant, cetyl trimethylammonium bromide (CTAB), forms hemimicelles on a HOPG substrate. These structures were then perturbed by the addition of isopropyl alcohol, which results in complex rearrangement of the micelle grain structure. The temporal resolution of the Cypher VRS is well-suited to capture these dynamics and provide insights into the processes that were previously inaccessible with other techniques.
Download the application note to learn:
- Introduction to the self-assembly of surfactant micelles at solid-liquid interfaces
- Challenges associated with characterizing the dynamic behavior of these systems
- New capability provided by video-rate AFM to visualize these dynamics
- Several example datasets and links to the full movies (see below)