title: Determination of emamectin benzoate in medicated fish feed: a multisite study.
abstract: A new method was developed for the quantitation of emamectin benzoate in medicated fish feed at levels between 1 and 30 ppm. The new procedure, based on a previously reported assay, consists of a wet methanolic extraction of ground feed, followed by solid-phase extraction and injection onto a gradient liquid chromatographic system. A multisite study involving 3 laboratories (the developing laboratory and 2 independent laboratories) was performed to evaluate precision, recovery, linearity, and sensitivity. Mean recove;ries for triplicate analyses at 3 levels, performed by 2 analysts per laboratory, were between 89 and 97%, with coefficients of variation ranging from 1.6 to 8.6%. Coefficients of determination (r2) obtained from the plotted data were > or =0.993. The precision of the method, determined from 6 replicate preparations from the same batch of medicated feed assayed in 3 separate trials per laboratory, was between 0.6 and 5.8%. The quantitation limit was established at 0.5 ppm. Specificity and robustness studies were performed by the developing laboratory.
authors.affiliation: Schering-Plough Research Institute, Analytical Development, 2000 Galloping Hill Rd, Kenilworth, NJ 07033, USA. LJF551@optonline.net
authors.forename: Leslie J
authors.initials: LJ
authors.lastname: Farer
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D002138:Calibration; D002853:Chromatography, Liquid; D005399:Fishes / Q000378:metabolism*; D007202:Indicators and Reagents; D007306:Insecticides / Q000032:analysis*; D007559:Ivermectin / Q000031:analogs & derivatives* / Q000032:analysis*; D012015:Reference Standards; D015203:Reproducibility of Results; D012996:Solutions; D013056:Spectrophotometry, Ultraviolet; D014481:United States; D014486:United States Food and Drug Administration
chemical_list: D007202:Indicators and Reagents; D007306:Insecticides; D012996:Solutions; D007559:Ivermectin; C108024:emamectin benzoate