Wedged AFM-cantilevers for parallel plate cell mechanics

Area of Science:

• Biophysics
• Cell Mechanics
• Microscopy Techniques

Background:

• Atomic force microscopy (AFM) combined with optical microscopy is increasingly used for living cell mechanical analysis.
• Existing AFM assays with tipless cantilevers offer insights into cell function, structure, and dynamics.
• A standard cantilever tilt angle (≈10°) hinders uniaxial loading, complicating cell geometry assessment and potentially causing cell displacement.

Purpose of the Study:

• To develop a method for achieving parallel plate mechanics in AFM assays using modified tipless cantilevers.
• To provide a comprehensive guide for fabricating, assessing, and calibrating these modified cantilevers.
• To demonstrate the advantages of wedged cantilevers for analyzing living cell mechanics.

Main Methods:

• Modification of tipless AFM cantilevers with precisely engineered wedges.
• Detailed guidance on material selection and the wedge fabrication process.
• Assessment of wedge properties and geometry, followed by cantilever calibration.

Main Results:

• Achieved proper parallel plate mechanics, enabling uniaxial loading of cells.
• Demonstrated simplified assessment of cell shape and geometry.
• Prevented lateral displacement of round cells during compression, enhancing data reliability.
• Improved the accuracy of cell mechanical property measurements.

Conclusions:

• Wedged tipless AFM cantilevers offer a significant advancement for accurate cellular mechanical analysis.
• This technique enhances the reliability of measurements by ensuring uniaxial loading and preventing cell displacement.
• The developed method provides a practical solution for researchers studying cell mechanics with AFM.