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Written by The Clever Chromatographer
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Thursday, 02 September 2010 18:18 |
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A recent article in the Journal of Separation Science entitled “Semi-preparative high-speed counter-current chromatography separation of alkaloids from embryo of the seed of Nelumbo nucifera Gaertn by pH-gradient elution” introduces a new gradient CCC method . In this study, the authors prepared and pre-equilibrated a diethyl ether/aqueous sodium phosphate buffer (pH 7.5) solvent system. The CCC column was filled by pumping a 50/50 mixture of the two phases into the column. The column was then equilibrated by pumping the aqueous mobile aqueous phase through the column prior to sample injection. After the sample was injected, the pH 7.5 buffer was gradually replaced by a pH 7.2 buffer. Amazingly, shake flask experiments had shown that the K values of the three target compounds, liensinine, isoliensinine, and nerferine changed significantly in a pH 7.5 aqueous phase compared to a pH 7.2 aqueous phase. It is worth noting that liensinine and isoliensinine are positional isomers. In this case, diminishing the pH of the aqueous phase by 0.3 pH units reduced the K values of the target compounds by a factor of four. The chromatogram resembles the classical CCC elution peaks rather than pH-zone refining “plateaus.”
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Last Updated on Thursday, 02 September 2010 18:20 |
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Written by Administrator
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Monday, 06 April 2009 06:56 |
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Dear User: This site was launched to provide a networking opportunity for all scientists and practitioners of counter-current chromatography, as well as those interested in modern liquid-liquid separation technology. While the resources on this website are in the process of being built, this menu provides links to external sites that offer significant information about CCC technology. Eventually, INCCC.NET intends to serve as a comprehensive, global resource for this purpose. While these activities are ongoing, "INCCC resources" are supplemented with information from external links.
The INCCC webteam |
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Last Updated on Monday, 06 April 2009 15:40 |
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