ISSN:
1040-7685
Keywords:
sample introduction
;
injection
;
supercritical fluid chromatography
;
open tubular columns
;
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
As in the case of all chromatographic methods, the ideal sample introduction method for supercritical fluid chromatography (SFC) would provide a narrow and sharp solvent peak (or no solvent peak), quantitative transfer of the sample into the column, and high reproducibility. Elimination of the solvent before the solutes enter the column would be preferred; however, this practice is always associated with the risk of partial solute elimination. In open tubular column SFC, samples are normally introduced using a smallvolume internal loop valve. These valves can be operated such that none, some, or all of the solvent is eliminated. Several approaches were quantitatively evaluted, and optimized conditions were determined. Particular attention was given to trace analysis. The minimum detectable levels (S/N 〉4) achievable using a flame ionization detector were determined to be approximately 30 ng (150 ppm) for split injection, 4 ng (20 ppm) for delayed split injection, and 1 ng (5 ppm) for direct injection.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mcs.1220030309
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