Unraveling the biophysical properties of chromatin proteins and DNA using acoustic force spectroscopy

Acoustic Force Spectroscopy (AFS) is a single-molecule micromanipulation technique that uses sound waves to exert force on surface-tethered DNA molecules in a microfluidic chamber. As large numbers of individual protein-DNA complexes are tracked in parallel, AFS provides insight into the individual properties of such complexes as well as their population averages. In this chapter, we describe in detail how to perform AFS experiments specifically on bare DNA, protein-DNA complexes, and how to extract their (effective) persistence length and contour length from force-extension relations