Abstract

Acoustic Force Spectroscopy: Using Sound to Investigate Molecules and Cells

Gijs Wuite, Assistant Professor, Vrije Universiteit

Single-molecule force spectroscopy has become an indispensable tool to unravel the structural and mechano-chemical properties of biomolecules and cells. In most force-spectroscopy instruments only a limited number of biomolecules or cells can be studied simultaneously, which reduces experimental throughput and limits statistics. At the same time, many independent measurements are required to distinguish the intrinsic stochasticity of the process of interest from heterogeneity. With Acoustic Force Spectroscopy (AFS) we extend the force-spectroscopy toolbox with an acoustic manipulation device that allows exerting acoustic forces on tethered molecules or cells. AFS is a Lab-on-a-chip device consisting of a flow cell of two glass plates with a fluid chamber in between and a piezo element glued on top. While applying an alternating voltage to the piezo element, forces from sub-pN to hundreds of pNs are exerted to thousands of biomolecules in parallel, with sub-millisecond response time and inherent stability. AFS already distinguishes itself by its relative simplicity, low cost and compactness, which allow straightforward implementation in lab-on-a-chip devices and these new developments make AFS an even more accessible technique, with a wider field of applications that can be integrated in almost every existing microscope.