Simultaneous Determination of Residual Antiparasitic Lactones in Bovine Muscle and Liver by Liquid Chromatography with Fluorescence Detection

Abstract

Abamectin, doramectin, eprinomectin, ivermectin, milbemectin, and moxidectin in bovine muscle and liver were extracted with acetonitrile. The extracts were partitioned with n-hexane and then evaporated to dryness. The residue was cleaned up on Bond Elute NH2 cartridge, and the drugs were eluted from the cartridge with methanol–ethyl acetate (3 + 7). The eluate was evaporated to dryness, and residues were derivatized with N,N-dimethyl-formamide–acetic anhyride-1-methylimidazole. The derivatives were determined by liquid chromatography with fluorescence detection. Recoveries of the 6 drugs were 79.6–63.8% in muscle and 71.6–60.6% in liver at 0.01 ppm levels. The quantitation limits were 5 ppb for each drug.

Determination of abamectin in soil samples using high‐performance liquid chromatography with tandem mass spectrometry

“…The presence of fecal material complicates sample assay due to the presence of plant particles and animal components. Current methods of sample extraction and separation include time‐consuming bench methods,8–23 while the commonly employed detection method, fluorescence, requires a derivatization step prior to analysis 8–23. The avermectins have been analyzed in a variety of matrices; however, to date, there have been no published methods for the analysis of the avermectins in soil samples by tandem mass spectrometry (MS/MS).…”