Asymptotical Correction to Bottom Substrate Effect Arising in AFM Indentation of Thin Samples and Adherent Cells Using Conical Tips

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Abstract

The bottom substrate effect is one of the major sources of error in force map studies of adherent cells and thin soft samples in an atomic force microscope (AFM)-based force spectroscopy. Because of this, samples appear stiffer than the natural. The popular Sneddon’s contact model, which assumes the sample as infinitely thick, fails to correct this error. In the present work, a simple asymptotically correct analytical correction to the bottom substrate effect is derived through contact mechanics approach and later the model is experimentally validated on a wide range of thickness of soft polyacrylamide gel and on adherent cells.

Keywords

Substrate effect correction Contact model AFM Indentation Stiffness 

Notes

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Supplementary material

11340_2018_373_MOESM1_ESM.docx (71 kb)
ESM 1 (DOCX 70 kb)

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Copyright information

© Society for Experimental Mechanics 2018

Authors and Affiliations

  1. 1.Department of Applied MechanicsIndian Institute of Technology DelhiNew DelhiIndia

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