Video-rate high-speed atomic force microscopy for biological sciences

The atomic force microscope (AFM) is unique in its capability to capture high-resolution images of biological samples in liquids. This capability becomes more valuable to biological sciences if AFM additionally acquires an ability of high-speed imaging. "Direct and real-time visualization" is a straightforward and powerful means of understanding biomolecular processes. With conventional AFM, it takes more than a minute to capture an image, while biomolecular processes generally occur on a millisecond timescale. In order to fill this large gap,various efforts have been carried out in the past decade. Here, we review these past efforts, describe the current state of the capability and limitations of our high-speed AFM, and discuss possibilities that may break the limitations, leading to an innovative high-speed bioAFM.