High-Speed Atomic Force Microscopy (AFM)

Introduction

High-speed atomic force microscopy (HS-AFM) was materialized by the optimization of all devices contained in the AFM system for fast scanning and by the new development of fast and precise control techniques (Ando et al. 2008). The state-of-the art HS-AFM system employing the sample stage-scan mode allows imaging biomolecules (proteins and DNA) at 10–20 frames/s (fps), without disturbing their function. Its spatial resolution is typically 2–3 nm in the lateral direction and 0.15 nm in the vertical direction. Despite this moderate spatiotemporal resolution, HS-AFM holds a unique and pivotal position among various tools for biological research. It is only HS-AFM that allows the simultaneous assessment of structure and dynamics of single molecules in action. A variety of purified protein systems have already been visualized (Ando et al. 2014). Even protein molecules on the surfaces of live bacteria and nuclei have also been visualized. The acquired molecular movies have...