English Thesis Title: Study of CE/MS in Chiral Separation Using Low Concentration and High Concentration Nonvolatile Cyclodextrin Buffer

• Main Authors: Wen-Shuo Cheng, 鄭文碩
• Other Authors: 何國榮
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/64362517781133483192

碩士 === 臺灣大學 === 化學研究所 === 98 === The counter-migration technique has been reported to couple low concentration charged cyclodextrin electrokinetic chromatography with electrospray ionization mass spectrometry detection without suffering ion suppression effect. However, if this approach is adoped to couple charged cyclodextrin electrokinetic chromatography with commercial CE-MS interface, the resolution could be decreased due to the depletion of charged cyclodextrin zone . With the use of a liquid-junction/low flow interface, the charged cyclodextrin migrated from the liquid junction reservoir to the separation column continuously to maintain the separation efficiency. However, certain enantioseparation operated under the condition that the higher concentration of cyclodextrin used to carry the analyte to achieve separation with negative polarity. A liquid-junction/low-flow interface was used to alleviate the ion separation by avoiding the entering of cyclodextrin into the ESI source. The charged cyclodextrin could be stayed in the liquid junction reservoir. Because of the higher interaction between the cyclodextrin and the analyte, the running buffer containing 20% methanol was added to the liquid junction reservoir to detach the cyclodextrin from the analyte. To avoid the entering of methanol into separation column during CD-EKC separation, a polyvinyl alcohol-coated column was used as the coating column. Both good chiral separation efficiency and low ion signal suppression could be achieved with this approach.