Running Title: High-speed atomic force microscopy techniques A Chapter in Methods in Enzymology

Atomic force microscopy enables direct visualization of single protein molecules in liquids at sub-molecular resolution. High-speed atomic force microscopy further makes it possible to visualize dynamic biomolecular processes at subsecond resolution. However, dynamic imaging of biomolecular processes imposes various requirements on “wet techniques ” and imaging conditions as well, which are often different from those for static imaging. This article first overviews the imposed requirements, then focuses on practical techniques associated with dynamic imaging, highlighting preparation of substrate surfaces, and presents examples of the use of these techniques. 1