The objective of the Physical Chemistry of Biological Systems (CPSysBio) group is to understand the chemico-chemical processes associated with the architecture and the functions of biological systems. Our studies cover a wide range of topics from isolated macro-molecules (proteins and protein complexes, protein-protein or membrane-proteins interactions, biomimetic systems) to complex cellular functions (cell adhesion, cell division, phagocytosis) or the collective behavior of cells in tissues. To achieve this aims, the group uses and develops interdisciplinary approaches involving physics, chemistry, biochemistry, molecular and cellular biology. Our studies uses a large variety of experimental techniques such as stationary or time-resolved absorption and fluorescence spectroscopies, fluorescence optical microscopy (videomicroscopy, FLIM, FRET), flow cytometry (SpICy platform) or IR spectroscopy coupled to AFM (MUSIICS). Some projects are developed in close collaboration with the three other groups of the Institute.