Acoustic Force Spectroscopy

L. Limozin and F. Rico

Acoustic force spectroscopy (AFS or Acoustic force probe) is a recent development that uses ultrasound waves allowing high-throughput applications of single biomolecule mechanics [1,2]. The idea is to use acoustic waves generated in a chamber to apply forces in parallel to hundreds of beads linked to individual molecules attached to the sample surface.

The amplitude of the acoustic wave modifies the gradients generated and thus the applied force that ranges from sub-pN to about 400 pN. Modulation of the excitation frequency modifies the position of the nodes along the chamber, allowing thus pushing from or pulling against the sample surface.

We are adapting AFS to study the interaction between receptor/ligand pairs of adhesion molecules and antibody/antigen complexes at ultraslow loading rates, down to 0.01 pN/s.

We are also combining it with microscopy techniques to directly work on living cells.

 

[1] G. Sitters, D. Kamsma, G. Thalhammer, M. Ritsch-Marte, E. J. G. Peterman, and G. J. L. Wuite, Nat Meth 12, 47 (2015).
[2] D. Kamsma, R. Creyghton, G. Sitters, G. J. Wuite, and E. J. Peterman, Methods 105, 26 (2016).

1200px-Logo_PACA_2018.svg

Our AFS system was acquired with funds from the region Provence-Alps-Côte d’Azur.