Finite element analysis of single cell stiffness measurement using PZT-integrated buckling nanoneedle

Abstract

In this project, we propose a new technique for real-time single cell stiffness measurement using PZT-integrated buckling nanoneedle. The PZT and the buckling part of the nanoneedle have been modelled and validated using ABAQUS software. The two parts are integrated together to function as single unit. After calibration, the stiffness, Young’s modulus, Poisson’s ratio and sensitivity of the PZT-integrated buckling nanoneedle have been determined to be 0.8600 Nm-1, 123.4700 GPa, 0.3000 and 0.0693 VmN-1 respectively. Three Saccharomyces cerevisiae yeast cells have been modelled using ABAQUS and validated based on compression test. We determine the average global stiffness and Young’s modulus of the cells to be 10.8867 ± 0.0094 Nm-1 and 110.7033 ± 0.0081 MPa respectively. The nanoneedle and the cell have been assembled to measure the local stiffness of the single Saccharomyces cerevisiae yeast cell. An indentation force of 0.2 μN equivalent to single mode eigenvalue which causes the nanoneedle to buckle has been applied along y-axis. The local stiffness, Young’s modulus and PZT output voltage of three different sizes Saccharomyces cerevisiae yeast cells have been determined at different environmental conditions. We investigated that, at low temperature the stiffness value is low to adapt to the change in the environmental condition as a result the cell is vulnerable to virus and bacteria attack. In future, the technique will supplement the present-day biochemical technique for diseases diagnosis.