Ce manuscrit expose le développement de méthodes bidimensionnelles en ligne pour l'analyse de composés chargés en couplage avec la spectrométrie de masse. Le contexte de l'étude et les principes théoriques de la chromatographie en phase liquide unidimensionnelle et bidimensionnelle sont tout d'abord présentés. Les conditions expérimentales telles que l'instrumentation, les colonnes, les composés étudiés sont détaillés. Des études unidimensionnelles ont été effectuées afin de connaître le comportement cinétique des petites molécules ionisables et des peptides selon la phase mobile et la température. L'orthogonalité de systèmes chromatographiques et les capacités de pics générées ont ensuite été étudiés afin de connaître les conditions expérimentales les plus intéressantes pour l'analyse des composés chargés. Les comparaisons de systèmes ont été effectuées avec de nouveaux descripteurs d'orthogonalité et de capacité de pic effective qui ont été établit. Les systèmes bidimensionnels LCxLC ont ensuite été mis en place. L'utilité d'un split pour réduire le volume injecté en seconde dimension est envisagée. Des limites en termes de volume injecté dans la seconde dimension ont été définies en RPLC et en HILIC. Des mélanges de peptides ont été séparés par RPLCxRPLC(-MS), RPLCxHILIC(-MS) et HILICxRPLC. Le couplage avec la spectrométrie de masse est optimisé. L'intérêt des séparations bidimensionnelles est mis en évidence par rapport à des séparations LC-MS classiques / This manuscript is dedicated to the development of on-line two-dimensional liquid chromatography for the analysis of charged compounds with mass spectrometry coupling. The context of the study and the theoretical principles of liquid chromatography in one or two dimensions are presented. Experimental conditions such as instrumentation, columns, studied compounds are detailed. Some one-dimensional studies have been experimented to know the kinetic behaviour of small ionisables molecules and peptides depending on conditions. The orthogonality of chromatographic system and generated peak capacity have then been studied in order to know which experimental conditions are the most interesting for the analysis of charged compounds. The comparisons of systems have been done with new descriptor for orthogonality and effective peak capacity. Two-dimensional systems were then set up. Some limits in term of injected volume in the second dimension have been established in RPLC and in HILIC. The usefulness of a split to reduce the injected volume in second dimension has been studied. Some peptides mixtures have been separated by RPLCxRPLC(-MS), RPLCxHILIC(-MS) and HILICxRPLC. The MS coupling has been optimized. The interest of two dimensional separations is underlined compared to classical LC-MS separations

This dissertation is dedicated to the topic of multidimensional liquid phase separations. This separation techniques are developed for analysis of complex samples containing thermally labile, low volatile or high molecular weight components that can´t be analysed by two-dimensional (2D) gas chromatography. Concepts of peak capacity and orthogonality are explained and various methods of their determination are stated in theoretical part of dissertation. High performance column liquid chromatography (HPLC) and high performance capillary electrophoresis (HPCE) are suggested as the most suitable methods for automated multidimensional liquid phase separations on-line coupled to mass spectrometry. Configuration of simplified miniaturized liquid chromatograph is described in experimental part of this thesis. Original concept of the system has been extended by simple mobile phase gradient generation technique. Correct function was demonstrated on repeatable separation of alkylphenones, peptides, nitroaromatics, and nitroesters. This system has been utilized as a base for a couple of simple two-dimensional separation platforms for HILIC-MALDI-MS analysis of glycans, for separation of peptides based on off-line coupling of isoelectric focusing and capillary liquid chromatography, and finally for on-line IEC×RPLC, RPLC×RPLC, and HILIC×RPLC two-dimensional liquid chromatography. Correct operation of submitted platforms has been proved.