Vladimir GAUTHIER : "Design and modeling for the control of trajectories in microlfuidic chips : application to cell sorting by dielectrophoresis"

Work thesis of  Vladimir Gauthier : "Design and modeling for the control of trajectories in microlfuidic chips : application to cell sorting by dielectrophoresis"

Abstract : This thesis proposes to integrate the principles of micro-robotics in a lab-on-a-chip in order to improve the performance of cell sorting by dielectrophoresis. Controlling the trajectory of cells in a fluidic chip in real time requires redesigning the chip, modeling it and developing control laws dedicated to realtime control. Concerning the design, this thesis is interested in the compromise existing between the speed of sorting and the problems of cell tracking in real time. An original architecture based on two electrode planes, on the upper and lower faces of the channels, is proposed. Manufacturing processes dedicated to this architecture are developed. In particular, the manufacture of transparent electrodes and the assembly of the two parallel electrode arrays are studied. Concerning the modeling, an analytical formulation of the electric field uncoupling control variables, terms depending on the position of the object and terms depending solely on the geometry of the chip is proposed in order to quickly and accurately calculate the dielectrophoretic force. An analysis of the anisotropy of the friction forces present near the electrodes completes the dynamic modeling of the behavior of the microparticles, and gives rise to a model compatible with real-time control, validated experimentally on artificial objects. Finally, a controller based on optimization techniques and a trajectory planner are proposed for cell sorting. A simulator is developed and highlights the good sorting performance of such a system. All of these methods will control the trajectory of biological cells in sorting chips to improve selectivity and speed.

Jury members :

 - Mr Michaël GAUTHIER CNRS Director Researcher, Université Bourgogne - Franche-Comté PhD Director
- Mrs Christine PRELLE Professor, Université technologique de Compiègne Reporter
- Mrs Marie FRENEA ROBIN Assistant Professor, Université de Lyon Reporter
- Mrs Aude BOLOPION CNRS Researcher, Université Bourgogne - Franche-Comté PhD Co-director
- Mr Zdenek HURAK Associate Professor Czech Technical University Reviewer
- Mr Pierre LAMBERT Professeur des Universités Université libre de Bruxelles Reviewer

Location : Amphithéâtre Jean-Jacques Gagnepain, Bâtiment TEMIS, 15B Avenue des Montboucons, 25000 Besançon