Submitted to: Royal Society of Chemistry Meetings
Publication Type: Abstract Only
Publication Acceptance Date: 6/23/1996
Publication Date: N/A
Technical Abstract: The capture and isolation of an extract from supercritical fluid extraction (SFE) is critical to achieving high analyte recovery and can be accomplished using several techniques. In this presentation we shall report on our experiences in the development and optimization of collection and sample preparation techniques such as solid phase extraction disks, sorbent cartridges, membrane filtration and liquid trapping. Rules for the selection of collection liquids and sorbent packings will be provided, based on fundamental physicochemical principles such as activity coefficients, sorption constants, and breakthrough volumes. Integration of solid phase extraction (SPE), in-situ in the extraction cell and in the collection mode after SFE, will be noted. Several examples will be provided of the above options as utilized for the SFE of foods and agricultural matrices. These will include the use of membrane filters for sample cleanup of extracts prior to EIA for pesticide residue determination, SPE sorbents for the analysis of drugs and cholesterol in meat products, and optimization of trapping conditions for volatiles and semivolatiles on collection sorbents. The optimization of factors which influence liquid trapping, such as analyte solubility in the collection solvent, cosolvent choice for SFE, and the relative volatility of the trapping solvent will also be presented.