Nanomechanical mapping of soft matter by bimodal force microscopy

TLDR

Bimodal force microscopy is a dynamic force‑based technique that simultaneously maps topography and nanomechanical properties of soft‑matter surfaces by exciting and detecting two cantilever eigenmodes, enabling quantitative measurements with few data points and separating topography from other interactions. The authors review the principles and applications of bimodal force microscopy for mapping mechanical properties of polymers and biomolecules. They discuss how the method achieves nanoscale spatial resolution of mechanical properties in air and liquid.

Abstract

Bimodal force microscopy is a dynamic force-based method with the capability of mapping simultaneously the topography and the nanomechanical properties of soft-matter surfaces and interfaces. The operating principle involves the excitation and detection of two cantilever eigenmodes. The method enables the simultaneous measurement of several material properties. A distinctive feature of bimodal force microscopy is the capability to obtain quantitative information with a minimum amount of data points. Furthermore, under some conditions the method facilitates the separation of the topography data from other mechanical and/or electromagnetic interactions carried by the cantilever response. Here we provide a succinct review of the principles and some applications of the method to map with nanoscale spatial resolution mechanical properties of polymers and biomolecules in air and liquid.