Integrated SFE/SFC/MS System for the Analysis of Pesticides in Animal Tissues

The development of an integrated system for an on-line supercritical fluid extraction/cleanup/supercritical fluid chromatography/mass spectrometry analysis (SFE/SFC/MS) of thermally labile carbamate pesticides from beef and chicken meat samples is discussed. A key to the system is the mixed stationary phase (7% diol in C 18 ) used in the cleanup column to separate target analytes from the extracted lipid matrix interferences. The detection limits of the system at 2:1 signal to noise ratio were 200 and 175 ppb for bendiocarb and carbaryl, respectively. The reproducibility of the present system was not totally favorable due to trapping problems, resulting from frequent clogging of either the cryogenic retention gap between the extraction cell and the SFC or the actual restrictor in the retention gap. Operating in an integrated mode, 53% of the experiments were completed without complications connected to extracting and detecting the analyte.