View source for Optical and Ultrasound Techniques for Probing and Modulating the Nano-Mechanical Properties of Live Cells

The mechanical properties of cells are deemed important in many areas of biology, from the very fundamental study of cell biology to the application of cells for therapeutic purposes in Regenerative Medicine. To date, the characterisation of live cells in culture is done using conventional biological analysis techniques, such as fluorescence-activated cell sorting - which requires the application of exogenous labels to the cells. Despite aiding the measurement of a specific aspect of the biological system, these techniques are either destructive or involve cell modifications. Therefore, we are looking for ways to characterise cells using non-destructive biomarkers, which is by studying the mechanical properties of cells - since on the nano-scale level, the mechanical properties of a cell are closely linked to its viability and function. 

The overall aim of this work is to use optical tweezers to probe the nano-mechanical properties of live cells in combination with electric and ultrasound approaches. Generally, the mechanical properties of a live cell is studied when the cell is probed using optical tweezers. Then, low intensity electric fields and ultrasound are used to apply stress to the cell. By doing this, the mechanical properties of the cell is being modulated. The change in mechanical properties after the modulation is going to be studied, again by using optical tweezers. The modulation of the mechanical properties of a cell using external cues can alter cell behaviour, particularly in the differentiation direction of stem cells, which is the long-term aim of this research.