Elastic and Viscoelastic Modeling of Cell Deformation in Acoustically Driven Microchannel

Application of acoustic waves in cell manipulation and cell separation is very usual these days but considering that the acoustic force can cause what kind of changes in cell shape, is a question right now. Under the influence of the ultrasound field in specific circumstances, cell deformation can occur. In order to model this deformation, elastic and shell models are usually used for simulation. In the current study, we present a numerical procedure to investigate the cell deformation based on the viscoelastic model while the cell is exposed to a bulk acoustic wave. Second-order acoustic pressure in the resonance frequency of 8 MHz is applied to cell boundary as an acoustic force and cell deformation is determined by solving the fluid-solid interaction (FSI) physics. Results show that the viscoelastic model predicts the cell deformation closer to experimental data relative to the elastic deformation model. Kelvin, Maxwell and SLS models are used to approximate a viscoelastic behavior. The present study shows that the Kelvin viscoelastic model is more compatible with experimental data compared with previous elastic and other viscoelastic models. By applying the Kelvin model, the root mean square error (RMSE) is obtained about 0.064 at 980kpa pressure amplitude. The effect of stiffness on aspect ratio is also investigated and it’s observed that the cell deformation decreases gradually by increasing Young’s modulus. Results also show that in the cases with stiffness up to the 600 pa in Young’s modulus, there’s a sharp drop in cell deformation.