Translation and optimization of supercritical fluid extraction methods to commercial instrumentation

Acceptance of supercritical fluid extraction (SFE) is partially impeded by the lack of confidence that analytical SFE methods can be reproduced on varying types of instrumentation. In this study, we have attempted to optimize and translate several SFE methods and techniques developed in our laboratories on noncommercial apparatus onto commercial instrumentation. The test cases involved the separation of incurred organochlorine pesticides from coextracted lipid material, total oil extraction from soybean flakes, and the extraction of various pesticide moieties from wheat. Utilizing four different commercial instruments, we achieved over 90 % recovery of the pesticide and lipid moieties from the above sample matrices using only supercritical C 0 2 at various extraction pressures. Reproducibility of the extractions on a particular instrument varied depending on the test method and the nuances of the extraction technique. Overall, the agreement between results obtained on each of the above instruments for a particular test was excellent; however, oil extraction results showed a pronounced dependence on extraction pressure