Bio-mechanical properties of human renal cancer cells probed by magneto-optical tweezers

We present the study of the biomechanical properties of human renal cancer cells utilizing the magneto-optical tweezers. In this work, a novel magneto-optical tweezers were designed by integrating a pair of electromagnets with optical tweezer. The magneto-optical tweezers were utilized to manipulate nano-sized magnetic particles which being uptaken by specific cancer cells. The biomechanical behavior of the renal cancer cells were measured by periodically applying plus magnetic field. To explore the mechanism underlying for the mechanical properties of compartments of cell, the mechanical equivalent models were applied to quantify the viscoelastic properties of cells such as viscosity, elasticity and relaxation time. The analyzed results have demonstrated that the experimental data can be well described by the modified Voigt model. The analyzed results imply that the elasticity of the compartment close to cell membrane is stiffer than that of cytoplasm, but viscosity is less than that of cytoplasm. Mechanism related to mechano-interaction of cell compartments will be discussed.