High Speed Scanning Ion Conductance Microscopy for Quantitative Analysis of Nanoscale Dynamics of Microvilli.

Observation of nanoscale structure dynamics on cell surfaces is essential to understanding cell functions. Hopping-mode scanning ion conductance microscopy (SICM) was used to visualize the topography of fragile convoluted nanoscale structures on cell surfaces under noninvasive conditions. However, conventional hopping mode SICM does not have sufficient temporal resolution to observe cell-surface dynamics in situ because of the additional time required for performing vertical probe movements of the nanopipette. Here, we introduce a new scanning algorithm for high speed SICM measurements using low capacitance and high-resonance-frequency piezo stages. As a result, a topographic image is taken within 18 s with a 64 × 64 pixel resolution at 10 × 10 μm. The high speed SICM is applied to the characterization of microvilli dynamics on surfaces, which shows clear structural changes after the epidermal growth factor stimulation.