Measurement of viscoelastic properties of living SMCC-7721 cells by atomic force microscopy

Elastic properties of carcinoma cells are frequently measured from which malignant cells could be distinguished from their benign counterparts. However, the viscoelastic properties of cancerous cells do not receive their deserved attention since biological cells are more or less viscous. In this regard, the goal of this study is to explore, verify and quantify the viscoelastic properties of human liver cancerous cells (SMCC-7721 cells). To accomplish this objective, creep tests are performed on single 7721 cells by using the constant force delay mode of atomic force microscopy (AFM), and the resulted indentation depth-time curve is fitted by a theoretical model which takes profile of AFM probe and viscoelastic constitution of 7721 cells into consideration. The result indicates that this theoretical model provides good fitting coincidence and the order of magnitude of the extracted parameters also coincides with that of previous studies.