| The analysis column (4.6 mm×250 mm) for the separation of EPA and DHA was prepared with Ag+ modified amino silica gel as stationary phase. A systematic evaluation on retention behavior of EPA and DHA in normal phase chromatography was performed. The influences of Ag+ modified amino silica gel with different pore sizes and mobile phase on the separation of EPA and DHA were researched. The results showed that the separation degree of 5 μm Ag+ modified amino silica gel was better than that of 10 μm Ag+ modified amino silica gel; the separation degree of EPA and DHA increased with the proportion of n-hexane in mobile phase increasing; when the pore size of Ag+ modified amino silica gel was 5 μm, the volume ratio of n-hexane to isobutanol was 2 000∶1, flow rate was 1 mL/min, ultraviolet detection wavelength was 210 nm and the injection volume was 5 μL, the separation degree of EPA and DHA was the best and reached 2.03. The method had the items of simpleness, rapidness and high reproducibility, which was suitable for the separation of EPA and DHA. |
