Title: Mechanical characterisation of human cartilage cells by AFM nanoindentation under different loading frequencies
Authors: Kexiang Hu; Limin Sun; Qingkang Wang
Internet of Things Research Center, China University of Mining and Technology, 1 Jinshan East Road, Quanshan District, Xuzhou 221008, China
Instrumental Analysis Center, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240, China
National Key Laboratory of Micro/Nano Fabrication Technology, Key Laboratory for Thin Film and Microfabrication Technology of Ministry of Education, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240, China
Abstract: In this paper, we employ the AFM tip indentation and Hertzian contact mechanics model to compute Young's modulus and the adhesion force of cartilage cells in different environments. The indentation is implemented under different loading frequencies to obtain the relationship between loading frequency and Young's modulus of both living and dead cartilage cells. The results show that the stiffness of the cell membrane is related to the loading frequency. Under the constant loading force, the indented depth decreases with the increase of frequency. The less the indented depth is, the stiffer the cell membrane will be, therefore, the larger the Young's modulus will be. This study also shows the adhesive force of living cartilage cells lies within the range from 150 nN to 350 nN, while the dead ones have the adhesive force between 30 nN and 90 nN.
Keywords: human cartilage cells; AFM nanoindentation; Hertzian contact mechanics; modelling; Young's modulus; adhesion force; mechanical characterisation; loading frequency; dead cells; living cells; cell membrane stiffness.
Int. J. of Nanomanufacturing, 2014 Vol.10, No.5/6, pp.500 - 512
Submission date: 07 Dec 2013
Date of acceptance: 30 Apr 2014
Available online: 11 Dec 2014