Liquid Chromatography/Fluorescence Method for Emamectin B1a and Desmethylamino-Emamectin B1a Residues in Lobster Tissue
Abstract:A liquid chromatography (LC)/fluorescence procedure was validated for emamectin (EM B1a) and desmethylamino-emamectin (DMAEM B1a) residues in lobster tissue. They were extracted by shaking and sonicating with 1% ammonium acetatemethanol in the presence of sand. The extract was concentrated, partitioned with ethylacetate, and cleaned up on a propylsulfonic cation exchange cartridge. The analytes were eluted from the cartridge with 5% ammonium hydroxidemethylacetate, the eluate was concentrated, and the solvent was changed to dry 20% ethylacetateacetonitrile before derivatization with trifluoroacetic anhydrideN-methylimidizole. The products were analyzed by LCfluorescence, and no interference [>limit of detection (LOD)] was detected in the control samples. Lobster tissues fortified with EM B1a and DMAEM B1a at 0.5, 5, 10, 25, and 50 ng/g gave overall mean recoveries of 96.7 12.4%, relative standard deviation (RSD) 12.8% for EM B1 and 83.6 12.1%, RSD 14.5% for DMAEM B1a. Regression analysis of the calibration data gave slopes of 0.90 (EM B1a) and 0.71 (DMAEM B1a) with an r2 0.99 for both compounds. The calculated LOD and limit of quantification (LOQ) for EM B1a were 1.10 and 3.32 ng/g, respectively, and for DMAEM B1a were 0.762 and 2.31 ng/g, respectively. Residues of EM B1a and DMAEM B1a in fortified lobster tissues stored at 20C showed that residues were stable for 1012 months. No loss of EM B1a and DMAEM B1a residues was observed after 3 freeze/thaw cycles of fortified tissue in a 5-day period.
Document Type: Research Article
Affiliations: 1: ETL/Xenos Laboratories, 13-210 Colonnade Rd, Nepean, ON K2E 7L5, Canada. 2: Kiel Pharma Laboratories, 95B Belfast Rd, Trooperslane Industrial Park, Carrickfergus, BT38 8BX, Northern Ireland. 3: Schering-Plough Research Institute, PO Box 32, 144 Route 94, Lafayette, NJ 07848.
Publication date: November 1, 2006
- The Journal of AOAC INTERNATIONAL publishes refereed papers and reviews in the fields of chemical, biological and toxicological analytical chemistry for the purpose of showcasing the most precise, accurate and sensitive methods for analysis of foods, food additives, supplements and contaminants, cosmetics, drugs, toxins, hazardous substances, pesticides, feeds, fertilizers and the environment available at that point in time. The scope of the Journal includes unpublished original research describing new analytical methods, techniques and applications; improved approaches to sampling, both in the field and the laboratory; better methods of preparing samples for analysis; collaborative studies substantiating the performance of a given method; statistical techniques for evaluating data. The Journal will also publish other articles of general interest to its audience, e.g., technical communications; cautionary notes; comments on techniques, apparatus, and reagents.
- Information for Authors
- Submit a Paper
- Subscribe to this Title
- Information for Advertisers
- Journal Information
- Ingenta Connect is not responsible for the content or availability of external websites