Development Of Microscale Liquid Phase Separation Techniques And Related Platforms

Proteomics demands high performance separation science due to its high complexity.Microscale separations have been developed rapidly according to its suitability to limit amount of biosamples as well as the trend of miniaturization for separation instrumentations.Microscale separations have advantages of higher resolution,less sample requirement and better separation throughput and therefore have the potential to fulfill proteomic separations.In this thesis,we chose capillary columns and droplet microfluidics to build microscale,high resolution separation platform and used it for high performance separation of proteomic samples.The work includes the following points:Chapter one discussed analytical methods for proteomics research,in which separation science and especially microscale liquid phase separation techniques were reviewed.The introduction provided references for the research and guided the developments of microscale separation platform targeting at complex proteomic samples.Chapter two studied droplet interfaced 2D RPLC-CZE.Due to droplet microfluidics' tiny volume,small disfussion and non-crosscontamination,it can greatly reserve first dimension's resolution and support the sample sample between first and second dimensions.Based on an off-line strategy,droplets can be transferred at a high resolution and enabled the optimum separation of each dimension.Droplet interface can greatly enhance 2D resolution and achieving a high peak capacity of 10000.Chapter three studied electrically enhanced liquic chromatography.Using 80 cm long capillary column,eLC was developed based on a nanoLC platform.Through applying 10s kV high voltage on the long column,resolution was greatly improved due to the combined mechanism of chromatography and electrophoresis.With complex peptide mixture as the sample,improved separation power was achieved.Chapter four reported packed column-based capillary electrophoresis.The technique realized highly reproducible CE separations and also allowed collection of CE effluent which can be used for post-separation characterization of the sample.Finally,Chapter five summarized the studies and outlooked the future work.