Rapid Determination of Pesticide Residues in Herbs Using Selective Pressurized Liquid Extraction and Fast Gas Chromatography Coupled with Mass Spectrometry
Institute of Chinese Medical Sciences, University of Macau, Taipa, Macao SAR, China. Journal of Separation Science
(Impact Factor: 2.74).
08/2012; 35(15):1922-32. DOI: 10.1002/jssc.201200169
A selective pressurized liquid extraction and gas chromatography coupled with triple quadrupole mass spectrometer method was developed for simultaneous determination of 52 pesticide residues in medicine and food dual-purpose herbs. The developed extraction method integrated extraction and cleanup processes for sample preparation. The sorbents, 5 g Florisil and 100 mg graphitized carbon black, were placed inside the extraction cell to remove matrix interferences. Optimized conditions of selective pressurized liquid extraction were ethyl acetate as extraction solvent, 120°C of extraction temperature, 6 min of static extraction time, 50% of flush volume extracted for two cycles. An ultra inert capillary GC-MS HP-5 UI column (20 m × 0.18 mm id, 0.18 μm) and column backflush system were used for the analysis. Multiple-reaction monitoring was employed for the quantitative analysis with electron ionization mode. All calibration curves showed good linearity (r(2) > 0.995) within the test ranges. The average recoveries of most pesticides were from 81 to 118%. The validated method was successfully applied for the determination of pesticide residues in four herbs. The results indicate that selective pressurized liquid extraction and GC-MS/MS is a sensitive and reliable analytical method for the simultaneous determination of multiple pesticide residues in herbs.
Available from: Matthew Edwards
- "GC × GC is considered an established separation technique and for the last decade focus has shifted away from the development of modulation technology to applying the technique to an ever increasing number of analytical challenges. Fields in which GC × GC applications are popular include petroleum and petrochemicals           ; food, flavours and fragrances              ; metabolomics             and environmental analysis       . Although GC × GC has never been more widespread, there are some applications that remain challenging for a chromatographer to perfect. "
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