Biomechanical Properties of Cells

It is known that the mechanical properties of a cell give insight into the state the cell is e.g. health or state of differentiation.
Within an interdisciplinary project we try to make a complete new approach to investigate the mechanical properties of a single cell. Our goal is to build a microscopic microphone as sketched below.
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Layout of the microphone approaching a cell


The basis of the microphone is a 1nm thick Carbon Nanomembrane (CNM) made out of a cross linked aromatic self-assembled monolayer in the workgroup of Prof Dr. Armin Golzhäuser (Uni Bielefeld). This membrane is highly flexible and furthermore shows interesting piezoresistive properties. This renders the membrane an ideal tool to receive weak sound waves and transform the sound into a measurable voltage drop.
To accomplish this, the membrane is immobilized on a silicon chip, which is custom-made in the working team of Dr. Thomas Weimann at the Physikalisch-Technische Bundesanstalt. This chip serves primary as a retainer, but also enables the efficient electrical contacting of the CNM.

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SEM of a Silicon Chip with Au/Pt contacts, CNM spanning over a hole under different pressures scanned with an AFM


With the help of this microphone it is/should be possible to detect weak sound waves emitted by a single cell, without inducing big amount of mechanical stress into the cell. These sound waves might be a passive echo-like reaction to an external sound signal or even have their origin in the internal processes of a living cell.