TY - JOUR
T1 - Quasi-linear viscoelastic properties of PC-12 neuron-like cells measured using atomic force microscopy
AU - Chen, Rung Jian
AU - Lin, Chou Ching K.
AU - Ju, Ming Shaung
N1 - Funding Information:
The research is supported by National Science Council of Taiwan via contract number NSC 96-2221-E-006-245 and NSC 96-2923-I-006-001-MY2. The AFM was supported by the Biomechanical Engineering Common Laboratory, Department of Mechanical Engineering, National Cheng Kung University. The authors also thank Chun-Hsiung Feng for his contribution to the AFM experiment.
PY - 2011/4
Y1 - 2011/4
N2 - Atomic force microscopy has been widely used to measure the mechanical properties of living cells. Models based on Hertz theory are often utilized to estimate the Young's modulus of cells. In practice, the nonlinear viscoelastic behavior of cells can often be observed in indentation experiments. In this article, the quasi-linear viscoelasticity (QLV) theory, which has been successfully applied to many biological tissues, was employed to construct the constitutive equation of neuron-like PC-12 cells. The values of Young's modulus obtained via our proposed method were one or two orders of magnitude, depending on the indenting rate, less than those obtained using methods based on the modified Hertzian model. The Kelvin model was also introduced to describe the solid and liquid behavior of cells. The prediction error of the Kelvin model was larger than that of the proposed QLV model, especially at the peak force and the toe portion of the force response. The results revealed that the Young's modulus estimated by the QLV model was less affected by indenting rates than that estimated by the modified Hertzian model or the Kelvin model. The proposed QLV model accounting for the indenting conditions was capable of describing both the nonlinear elastic response and relaxation behavior and, therefore, was more appropriate for modeling the biomechanical behaviors of PC-12 cells than the nonlinear elastic model or the linear viscoelastic model.
AB - Atomic force microscopy has been widely used to measure the mechanical properties of living cells. Models based on Hertz theory are often utilized to estimate the Young's modulus of cells. In practice, the nonlinear viscoelastic behavior of cells can often be observed in indentation experiments. In this article, the quasi-linear viscoelasticity (QLV) theory, which has been successfully applied to many biological tissues, was employed to construct the constitutive equation of neuron-like PC-12 cells. The values of Young's modulus obtained via our proposed method were one or two orders of magnitude, depending on the indenting rate, less than those obtained using methods based on the modified Hertzian model. The Kelvin model was also introduced to describe the solid and liquid behavior of cells. The prediction error of the Kelvin model was larger than that of the proposed QLV model, especially at the peak force and the toe portion of the force response. The results revealed that the Young's modulus estimated by the QLV model was less affected by indenting rates than that estimated by the modified Hertzian model or the Kelvin model. The proposed QLV model accounting for the indenting conditions was capable of describing both the nonlinear elastic response and relaxation behavior and, therefore, was more appropriate for modeling the biomechanical behaviors of PC-12 cells than the nonlinear elastic model or the linear viscoelastic model.
UR - http://www.scopus.com/inward/record.url?scp=84862956352&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84862956352&partnerID=8YFLogxK
U2 - 10.1080/02533839.2011.565609
DO - 10.1080/02533839.2011.565609
M3 - Article
AN - SCOPUS:84862956352
VL - 34
SP - 325
EP - 335
JO - Chung-kuo Kung Ch'eng Hsueh K'an/Journal of the Chinese Institute of Engineers
JF - Chung-kuo Kung Ch'eng Hsueh K'an/Journal of the Chinese Institute of Engineers
SN - 0253-3839
IS - 3
ER -