Experimental Verification of the Elastic Formula for the Aspirated Length of a Single Cell Considering the Size and Compressibility of Cell During Micropipette Aspiration
In this study, an aspiration system for elastic spheres was developed to verify the approximate elastic formula for the aspirated length of a single solid-like cell undergoing micropipette aspiration (MPA), which was obtained in our previous study by theoretical analysis and numerical simulation. Using this system, foam silicone rubber spheres with different diameters and mechanical properties were aspirated in a manner similar to the MPA of single cells. Comparisons between the approximate elastic formula and aspiration experiments of spheres indicated that the predictions of the formula agreed with the experimental results. Additionally, combined with the MPA data of rabbit chondrocytes, differences in terms of the elastic parameters derived from the half-space model, incompressible sphere model, and compressible sphere model were explored. The results demonstrated that the parameter ξ (ξ = R/a, where R is the radius of the cell and a is the inner radius of the micropipette) and Poisson’s ratio significantly influenced the determination of the elastic modulus and bulk modulus of the cell. This work developed for the first time an aspiration system of elastic spheres to study the elastic responses of the MPA of a single cell and provided new evidence supporting the use of the approximate elastic formula to determine cellular elastic parameters from the MPA data.
KeywordsCell mechanics Micropipette aspiration Cell model Mechanical properties Experimental verification
Supports from the National Natural Science Foundation of China (Grant Nos. 11572213, 11632013, 11702184 and 11472185), the Natural Science Foundation of Shanxi Province, China (Grant No. 2014021013), and the Youth Funds of Taiyuan University of Technology (No. 2013T079) are acknowledged.
Conflict of interest
None of the authors have any competing financial interests related to this paper.
- 4.Boudou, T., J. Ohayon, Y. Arntz, G. Finet, C. Picart, and P. Tracqui. An extended modeling of the micropipette aspiration experiment for the characterization of the Young’s modulus and Poisson’s ratio of adherent thin biological samples: numerical and experimental studies. J. Biomech. 39:1677–1685, 2006.CrossRefPubMedGoogle Scholar
- 14.Hu, W. J., H. Chen, K. Zhang, and X. Chen. Effect of porosity on the properties of open cell silicone rubber foam materials. China Rubber Ind. 45:647–651, 1998; ((In Chinese)).Google Scholar
- 20.Li, Y. S. Study on the mechanical models for micropipette aspiration of cells. Thesis for the Doctor Degree of Taiyuan University of Technology, pp. 51–52, 2014 (In Chinese).Google Scholar
- 27.Pachenari, M., S. M. Seyedpour, M. Janmaleki, S. B. Shayan, S. Taranejoo, and H. Hosseinkhani. Mechanical properties of cancer cytoskeleton depend on actin filaments to microtubules content: investigating different grades of colon cancer cell lines. J. Biomech. 47:373–379, 2014.CrossRefPubMedGoogle Scholar
- 34.Timoshenko, S. P., and J. N. Goodier. Theory of Elasticity (3rd edition). New York: McGraw-Hill Book Company, 1970.Google Scholar
- 37.Xie, J. J., W. J. Hu, and J. L. Tao. Quasi-static experimental study on the energy dissipation performance of foam rubber based on quasi static. China Meas. Test. Technol. 38:29–32, 2012; ((In Chinese)).Google Scholar
- 38.Zhang, Q. Y. Mechanical properties of chondrocytes from normal and osteoarthritic rabbit knee cartilage. Dissertation for the Master Degree of Taiyuan University of Technology, 2006 (In Chinese)Google Scholar