| Cell membrane plays essential roles in the fundamental biological process of the cell, including the exchanges of the material and energy between the cell and its environments. It's not only the boundary of the cell structure, but also the defender for the intracellular environment. The lipids in plasma membrane known as membrane lipids (MLs) are the basic skeleton of the plasma membrane. Membrane proteins (MPs) are the main executors of the membrane function. MLs are related to many serious human diseases. In addition, more than half of the known MPs are predicted to be pharmacological targets. Therefore, the studies on MLs and MPs will play key roles in clinical diagnosis and drug development. Due to the complexility of biological samples, separation of different components is the first requirement for the further sample analysis. This is also the same case for study MLs and MPs. In orde to obtain a higher detection resolution, there is an urgent need for efficient extraction, purification, on line separation technology and other analytical tools linked with mass spectrometry (MS) for higher detection rate. Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS), high performance liquid chromatography mass spectrometry (HPLC-MS) and capillary electrophoresis mass spectrometry (CE-MS) based on electrospray ionization (ESI) interface technologies provide a good platform for studying the complex components of the cell membrane.Here we selected MLs and MPs in cell membrane, focus on current biomedical research difficulties, combined with a variety of mass spectrometry and separation techniques, optimized the extraction conditions, purification methods, on-line separation means, qualitative and quantitative analysis techniques for glycolipids, phospholipids, membrane proteins.In lipid A of LPS, we developed a MALDI-MS-based method with optimized matrix system for simultaneous analysis of cardiolipin (CL) and lipid A in H. pylori cells from as little as a single colony. The results suggest that environmental stresses could induce the expression of certain regulatory systems affecting fatty acid composition of lipid A and CL that in turn could induce the conversion from spiral to coccoid form in H. pylori. This is the first report of simultaneous analysis of CL and lipid A from ex vivo cells of H, pylori. In order to make up for shortcomings of MALDI-TOF-MS process, such as ionization mutual inhibition in the mixture, low content and poor ionization material can not be detected because of ionization suppression. Here we developed a HPLC-MS system combined with amide column on line separation and identification for endotoxin lipid A in the LOS of C.jejuni.In phospholipids of membrane, we achieved relative quantitative analysis of serum samples phosphatidylcholine (PC) and lysophosphatidylcholine (LPC) by using capillary electrophoresis combined with mass spectrometry (CE-ESI-MS), further validate the mechanism of the molecular pathology of Alzheimer's disease.In membrane proteins, we demonstrated the use of a microfluidic aqueous two-phase system combined with HPLC-MS for the purification and identification of membrane proteins. Results indicated that efficient purification of membrane proteins could be achieved within 5-7 s with approximately 90% of the purified proteins were membrane proteins. This new technology solved the problem that membrane components and other complex biological samples have to be purified before separation and identification of chromatogram and mass spectrometry.In conclusion, we developed a new sample purification system, using a variety of separation and coupling techniques, for the purification, qualitative and quantitative analyses of cell membrane components. This new methods not only provides important information for the study on ML and MP, but also provides important references for the analysis and identification of membrane components or sub-cellular components, as well as other complex biological samples.
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