On‐line supercritical fluid extraction/chromatography system for trace analysis of pesticides in soybean oil and rendered fats

A method for trace analysis incorporating solid phase extraction (extraction and clean‐up) with supercritical fluid chromatography (SFC) for analytes in fats and oils has been developed. Direct coupling (on‐line) of supercritical fluid solid phase extraction with supercritical fluid chromatography (SESPE/SFC) allows analysis of solutes in fats and oils for which on‐line SFE/SFC is unsuitable. The main feature of SFSPE/SFC is that extraction and clean‐up are accomplished in one step using unmodified supercritical carbon dioxide. Extraction/clean‐up is monitored by a photodiode array detector which allows fractionation. The operational set‐up and potential usefulness of the SFSPE/SFC system and applications for pesticide analysis of lipid sample matrices are described.