| Summary: | 碩士 === 國立中正大學 === 化學暨生物化學研究所 === 106 === Supercritical fluid chromatography (SFC) uses a nontoxic medium, supercritical carbon dioxide, with some amount of organic solvents as the co-solvents for separation. Therefore, the amount of organic solvent used in SFC is far less than that of conventional HPLC. Therefore, SFC is regarded as a green analytical technique. However, most SFC separations directly adapt traditional HPLC columns that are not designed for SFC and lead to poor separation performance, as compared with that of HPLC. Thereby SFC does not meet the expectation and becomes a less favor chromatographic technique since its invention. The use of right column is one of the main tasks to improve SFC performance. So far there are very few specific design columns for SFC. Our group is the first one to explore the use of ionic liquid functionalized stationary phases as SFC columns. Since the ionic liquid stationary phases can provide several kinds of molecular interactions: hydrophilic interaction, hydrophobic interaction, electrostatic forces, π-π interactions and hydrogen bonding, we can tune the interactions by varying the structure of ionic liquid stationary phases. With the feature of multimode interaction from the ionic liquid column, it is feasible that a single column can effectively separate the mixture of different functional compounds.
In part I of the study, supercritical fluid chromatographic separations of curcuminoids were screened with ionic liquid and commercial columns. MPS-BIm-BS(EC) column has the best resolution for separating curcuminoids in 7 min. The coefficient of determination(R2) upper than 0.9926, and detection limits up to 1.31 ppm. We also pretreat and determinate the content of curcuminoids in turmeric root, supplement foods, and Chinese medicine to show the usefulness of this method.
Part II of the study is to employ a 2-EP column with SFC on the extraction curcuminoids from turmeric root. The best extraction condition were optimized via multiple regression analysis. The SFC analysis indicates that 47% of curcuminoids can be extracted from turmeric root.
Part III of the study using HPLC-UV-ELSD system and SilprIm2C9BS column for the separation of furfural, HMF, arabinose, fructose, glucose and cellobiose, the products of cellulose hydrolysis. With the optimized separation conditions, the mixture can be separated in 18 min and the coefficient of determination(R2) is higher than 0.9904. The UV detection limits for furfural and HMF are about 1.31 ppm and ELSD detection limits of saccharide are about 6.59 ppm.
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