High-speed force spectroscopy: microsecond force measurements using ultrashort cantilevers

Area of Science:

• Biophysics
• Cellular Mechanics
• Nanotechnology

Background:

• Understanding biological processes necessitates characterizing mechanical properties of proteins and cells.
• Biological systems exhibit dynamic responses across nano- and microscales, requiring broad force measurement capabilities.
• High-speed atomic force microscopy (HS-AFM) offers video-rate analysis of biomolecular and cellular dynamics.

Purpose of the Study:

• To review the principles, developments, and applications of high-speed force spectroscopy (HS-FS).
• To highlight the utility of ultrashort cantilevers in probing molecular and cellular mechanics.
• To demonstrate HS-FS's capability in studying dynamics across various length and time scales.

Main Methods:

• Utilizing high-speed atomic force microscopy (HS-AFM) with ultrashort cantilevers.
• Implementing high-speed force spectroscopy (HS-FS) for dynamic mechanical measurements.
• Applying HS-FS to investigate protein unfolding, receptor/ligand unbinding, and cellular viscoelasticity.

Main Results:

• HS-FS achieves sub-microsecond time resolution, probing molecular events at velocities comparable to molecular dynamics simulations.
• HS-FS on living cells reveals short-timescale viscoelastic responses and cytoskeleton dynamics.
• The technique provides access to mechanical properties across a wide range of length and time scales.

Conclusions:

• HS-FS using ultrashort cantilevers is a powerful tool for dissecting molecular and cellular mechanics.
• This method offers unprecedented insights into the dynamic behavior of biological systems.
• HS-FS significantly advances the study of biomechanics at the nanoscale.