Preparation And Characterization Of Novel Fibrous Core-shell Stationary Phase And Its Application In Pressurized Capillary Electrochromatography

According to Van Deemter equation,the lower the particle size,the higher the column efficiency.But the smaller particle also brings the problem of high back pressure.The traditional core shell material itself has the advantages of fast flow rate and relatively low back pressure which has been more and more frequently used for high separation performance.Nowadays,commercial core-shell packing materials have become popular used.pCEC is a hybrid of HPLC and CE,which can effectively solve the problem of high back pressure.Apart from CEC,flow pressure is added to pCEC to suppress the bubble generation as well as to prevent the phenomenon of dry column.Since the core-shell application within pCEC is still rare,further study with this promising analysis technique should be explored.Two different fibrous core-shell particles(2.7 ?m and 1.2 ?m)were successfully synthesized and characterized.All the results showed that the novel fibrous core-shell material is worth doing further research.After that,an available way to detect nine antioxidants and preservatives was successfully established with pCEC and was immediately applied to detecting the red wine sample.The thesis was divided into seven chapters.The first chapter was about the basic theory and application of CEC,pCEC,and an overview of column preparation and classification and progress in packing material,core-shell packing material and fibrous core-shell packing material.Chapter two to chapter five introduced the details of the way to prepare two different fibrous core-shell particles(2.7 ?m and 1.2 ?m)and to investigate their character with SEM,TEM,BET test,and chromatographic properties with pCEC.The results showed that the diameter of the particle was homogeneous and the size distribution was narrow.By modified with C18,reverse phase chromatography packing column was made and was applied to separating five benzene Series and chiral drugs.The column efficiency of toluene was 113,232 plates per meter.2.7 ?m silica microsphere packing material with fibrous shells was successfully applied to determining the nine antioxidants and preservatives in red wine with a simple,rapid and reliable method after optimization of the separation conditions by pCEC.The linear coefficient was greater than 0.999.The LODs(limite of detection)were in the range from 0.3 ?g/mL to 8.3 ?g/mL while the repeatability was ranged from 0.40% to 1.61%.Good recoveries of 93.3–105.7% were achieved.1.2 ?m fibrous C18-modified core-shell was applied to separating eight neutral compounds and the highest column efficiency reached 190,000 plates per meter.The sixth chapter was about exploring the effective and reliable packing column method with a series of experiments,and also develop a new and efficient packing method.The final chapter was a summarize to the project and the prospect of the further research.