Dionex ASE 150, Руководство оператора

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ASE 150 Operator’s Manual
156
Doc. 065207-02 9/08
ASE has been shown to work well for the extraction of acrylamide from many
food matrices (32). The use of adsorbents in the ASE cell has now been extended
to this application (33). Florisil was added to the cell when extracting coffee or
chocolate samples. The authors report that 6 g of Florisil in the cell, along with 2 g
of sample, produced clear extracts without any interferences.
Figure E-4 shows
the effect of varying the level of the Florisil.
One of the most fascinating uses of selective extraction with ASE was reported by
Poerschmann et al. (34, 35). In this work, a combination of adsorbents in the cells,
varying temperature, and solvent allowed fractionation to be achieved that was
superior to conventional SPE after exhaustive extraction. This work demonstrated
the fractionation of lipid classes using sequential extractions. Unmodified silica
and cyanopropyl silica were used as the adsorbents in the outlet of the cells. The
biological samples were extracted with hexane/acetone (9:1, v/v) at 50 °C to
remove the neutral lipids. Then, the same samples were extracted with
chloroform/methanol (1:4, v/v) at 110 °C to remove polar lipids such as
phospholipids and hydroxy-containing fatty acids. What was intriguing about this
work was that the authors demonstrated that this fractionation scheme could be
Figure E-4. Residual co-extractives after the ASE extraction of a coffee sample trapped
on an SPE cartridge, the ASE cells containing from 0 to 6 g Florisil. From left to right: 1) No
Florisil in the ASE cell, 2) 2 g Florisil in the ASE cell, 3) 4 g Florisil in the ASE cell, and 4)
6 g Florisil in the ASE cell.