The aim of this thesis was the development of different supramolecular approaches, like MS and IM-MS, to characterize precisely protein/ligand interaction and to analyze complex mixtures of proteins. Understanding of supramolecular MS instruments and instrumental and methodological optimizations were allowed the development of MS and IM-MS to characterize very high mass supramolecular assembly. Thus, we were able to follow by kinetic the formation of protein/ligand interaction as well as associated conformational modifications, showing the interest of IM-MS coupling in pharmaceutical research. Furthermore, this work deals with the study of high mass complexes and assessment of IM-MS to obtain structural information on these complexes. As a consequence, we have pushed away some limits of MS allowing the use of this technique in structural biology.