Precise determination of elastic modulus of cell using conical AFM probe

Weihao Sun; Jianli Ma; Chao Wang; Heng Li; Chengwei Wu; Wei Zhang

doi:10.1016/j.jbiomech.2021.110277

Precise determination of elastic modulus of cell using conical AFM probe

J Biomech. 2021 Mar 30:118:110277. doi: 10.1016/j.jbiomech.2021.110277. Epub 2021 Jan 30.

Authors

Weihao Sun¹, Jianli Ma¹, Chao Wang¹, Heng Li¹, Chengwei Wu¹, Wei Zhang²

Affiliations

¹ State Key Laboratory of Structure Analysis for Industrial Equipment, Department of Engineering Mechanics, Dalian University of Technology, Dalian 116024, China.
² State Key Laboratory of Structure Analysis for Industrial Equipment, Department of Engineering Mechanics, Dalian University of Technology, Dalian 116024, China. Electronic address: wei.zhang@dlut.edu.cn.

PMID: 33556889
DOI: 10.1016/j.jbiomech.2021.110277

Abstract

The Sneddon formula is conventionally used to calculate the elastic modulus of cell based on atomic force microscope (AFM) experiments. Owing to the disobedience of the formula assumptions, errors exist. Here, the ABAQUS for finite element modeling and analysis was used to simulate the process of compression of cell with a AFM conical probe. It was found that the relative error ranges from 0.094 to 1.455 folds, depending on half angle of the cone, curvature radius at the tip of the cone and the compression depth. By fitting the error data, we proposed a correction factor, which can be multiplied by the Sneddon formula to get a modified formula, providing the more accurate elastic modulus of cell. The experimentally measured elastic moduli of cell and hydrogel are in good agreement with the values obtained using the modified formula.

Keywords: Cell; Elastic modulus; Numerical simulation; Sneddon formula.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Elastic Modulus
Hydrogels*
Microscopy, Atomic Force

Substances

Hydrogels