Optically and Electrically assisted Micro-Indentation

In this thesis, I present the development of two new instruments based on ferrule-top indentation, where the indentation technique is combined with OCT and with HD-MEA, respectively. By combining indentation with OCT imaging, it is possible to measure the viscoelastic properties of living tissues while simultaneously investigating tissue morphology in situ. This approach has been tested on in vivo and formaldehyde-fixed chicken embryos. The combination of HD-MEA recordings with micro-indentation offers a unique opportunity to investigate the interplay between mechanical forces and electrical signaling in neuronal tissues. This allows one to precisely monitor over a wide portion of biological tissue the functional effects that controlled mechanical stimuli induce on the electrophysiological activity of single neurons in neuronal tissue. Since mechanical stress can modulate physiological processes at the molecular and cellular levels, we expect that these tools will be a significant step forward in identifying new insights on the relationship between altered mechanosensitive signaling, stiffness, and pathologies [100].