Nanomechanical mapping of soft matter by bimodal force microscopy

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. (C) 2013 Elsevier Ltd. All rights reserved.