| Capillary electrophoresis interaction analysis (CEIA) is a kind of method to analyze the interaction among molecules with capillary electrophoresis. The advantages of CEIA includes: instrument will not influence the interaction among the molecules; the interaction can be measured directly in the true or emulational system. But in CEIA study, one of the molecules in the interaction pairs must be charged. Therefore, the rang of CEIA is limited in the charged molecules. To extend the applied rang of CEIA, the charged micelle, which is formed in the presence of surface active agent, is used. Effective mobility is imparted to the object molecules through hydrophobic interaction (this point is similar to the micellar electrokinetic capillary chromatography). Then, the effective mobility change of these object molecules, which is caused by other molecules, is determined. The method of CEIA in the neutral molecules is founded in the way. Through the model design and data process, the interaction between the neutral host-guest can be gained, and the interactions between them and micelle can also be obtained respectively.In this paper, the neutral molecules have been imparted apparent mobilities by sodium dodecyl sulfate (SDS) micelle, which has negative charge and negative apparent mobilities. The 18-crown-6 and p-nitro-aniline are used as samples of neutral molecules, and they can form a neutral supramolecule by interaction. Through the research, an interaction analysis method by using capillary electrophoresis is set up. The logarithm of binding constant of 18-crown-6 with p-nitro-aniline is obtained to be 4.14. In addition, it is found that there are comparative differences of hydrophobicity between 18-crown-6 and p-nitro-aniline to SDS respectively. Further more, for multiple interactions, the interaction analysis method of supramolecules has also been set up, which has more accuracy and availability. The logarithms of binding constant of 18-crown-6 to 2-aminopyridine and SDS, and 2-aminopyridine to SDS are obtained to be 3.65, 3.13 and 1.15 respectively. The principles, available experimental conditions, and assumptions in the measurement have been discussed too. This approach in this paper could be developed as an interaction analysis method of multiple components in complex system. Corresponding to the competitive interaction happened among the neutral guest, charged micelle, and neutral host, it is also a new method to analysis the competitive interaction among molecules by capillary electrophoresis. In the thesis, the method to separate the sibutramine enantiomers is also studied. For the first time, sibutramine enantiomers were separated by adding chiral selector, β-cyclodextrin, into mobile phase. Just in five minutes, the enantiomers were separated entirely. Experimental results show that resolution of sibutramine enantiomers is 3.2 when the concentration of β-cyclodextrin is 0.8 mmol/L, which is optimal. In contrast, the resolution is less than 3.2 whenever the concentration of β- cyclodextrin is more or less than 0.8 mmol/L. In addition, results show that sibutramine enantiomers' UV absorption are related to the concentration of β-cyclodextrin. On the basis of the results, the reason that β-cyclodextrin has the optimal concentration was discussed. The primary mechanism of the chiral separation was also discussed. The separation effect, which is influenced by the competitive interaction between enantiomers and the β-cyclodextrin on the solid phase & in the mobile phase, is studied. And the existence of β-cyclodextrin in the column is also illustrated.
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