Stefano Maggiolino

A completely transparent MEMS for mechanical properties evaluation of a single living cell

This research involves a new approach for the study of the mechanical properties of single living cells. The main idea is to use micro electro mechanical systems (MEMS) to investigate the Young modulus and the morphological modification of cells from the engineering point of view. Many different techniques already exist for a local cell analysis but our goal is to be able to test the properties of a single adherent cell in his complexity. We realized a completely transparent device which is versatile and can be coupled with other analysis tools such as atomic force microscopy (AFM) and patch clamp. Starting from a transparent wafer we developed a system to obtain high transparency suspended structures. All structures are made by using micro fabrication techniques. Our MEMS is composed by 3 main parts: (i) testing, (ii) measurement and (iii) actuation area.

A study on the cellular structure during stress solicitation induced by BioMEMS

The investigation of single cells is a topic in continuous evolution. The complexity of the cellular matrix, the huge variety of cells, the interaction of one cell with the other are all factors that must be taken into consideration in the study of the cellular structure and mechanics. In this project, we developed different types of bioMEMS for cells stretching, both transparent devices based on silicon nitride and non-transparent silicon based. While the use of silicon devices is limited to reflection microscopes, transparent bioMEMS can be used with transmission and reflection microscopes but can also be easily coupled with other tools such as patch clamp analyzers or atomic force microscope. This improvement will open brand new possibilities in the biological investigation field. We used these two BioMEMS to stretch a single cell in a controlled way and, as a first investigation, we focused on its morphology. We noticed that during a controlled stretch, cells react to the applied deformation. A hysteretic behavior on the ratio between area and perimeter has been highlighted.