Visualization of molecular binding sites at the nanoscale in the lift-up mode by amplitude-modulation atomic force microscopy

Nanoscale. 2021 Feb 25;13(7):4213-4220. doi: 10.1039/d0nr06125e.

Abstract

We report a new approach to visualize the local distribution of molecular recognition sites with nanoscale resolution by amplitude-modulation atomic force microscopy. By integrating chemical modification of probes, photothermal excitation to drive a cantilever, and lift-up scanning over surface topography, we successfully visualized binding sites provided by streptavidin on a solid surface for biotin attached on an AFM probe. The optimization of measurement conditions was discussed in detail, and the application of the technique was verified with a different ligand-receptor system.