Title: | Selective pressurised liquid extraction of halogenated pesticides and polychlorinated biphenyls from pine needles |
Address: | "Department of Chemistry, University of Otago, Dunedin 9016, New Zealand" |
DOI: | 10.1016/j.chroma.2012.08.042 |
ISSN/ISBN: | 1873-3778 (Electronic) 0021-9673 (Linking) |
Abstract: | "Pine needles are an ideal matrix for the long-term monitoring of semi-volatile organic compounds in the atmosphere because they are naturally occurring and distributed worldwide. However, typical extraction methods result in the co-elution of matrix-interfering compounds and thus require time-consuming clean-up steps. A selective pressurised liquid extraction method (S-PLE) for extracting current-use pesticides, historic-use pesticides and polychlorinated biphenyls (PCBs) from pine needles that does not require additional clean-up steps was developed and validated. The selective extraction was achieved by packing the extraction vessel with a fat retainer, Florisil, down-stream of the pine needle matrix. A fat to fat-retainer ratio of 0.0057 (corresponding to 35 g of Florisil per 10 g of pine needle sample) was selected to minimise the co-elution of matrix-interfering compounds. Three 5-min extractions were performed using 25:75 (v/v) dichloromethane:n-hexane and a solvent flush of 150%. The mean recovery of spiked current-use pesticides, historic-use pesticides and PCBs using this method was 71%, 72%, and 84%, respectively. The method was validated by comparing target analyte concentrations measured in a pine needle sample using the optimised S-PLE method to those obtained using a conventional PLE method with external clean-up. The method detection limits and reproducibility were similar for the two methods; however, sample preparation time was 67% shorter when using the S-PLE method" |
Keywords: | Hexanes/chemistry Limit of Detection Lipids/chemistry Liquid-Liquid Extraction/*methods Pesticides/analysis/*isolation & purification Pinus/*chemistry Plant Leaves/chemistry Polychlorinated Biphenyls/analysis/*isolation & purification Pressure Reproducibi; |
Notes: | "MedlineLavin, Karen S Hageman, Kimberly J eng Research Support, Non-U.S. Gov't Netherlands 2012/09/04 J Chromatogr A. 2012 Oct 5; 1258:30-6. doi: 10.1016/j.chroma.2012.08.042. Epub 2012 Aug 17" |