title: Analytical procedure for determination of the time profile of eprinomectin excretion in sheep faeces.
abstract: An analytical procedure has been introduced to enable study of the time profile of eprinomectin excretion in sheep faeces. Eprinomectin was extracted from sheep faeces with acetonitrile, the extract was cleaned by solid-phase extraction (SPE), and, after derivatization by reaction with N-methylimidazole, trifluoroacetic anhydride, and acetic acid, eprinomectin was analysed by high-performance liquid chromatography (HPLC) with fluorescence detection. The method has a low detection limit (1.0 ng g(-1) of moist sheep faeces), a low quantification limit (2.5 ng g(-1) of moist sheep faeces), good recovery (in the range 78.8 to 87.1%), and good reproducibility (RSD<10%). The method was used to study the time-profile of excretion of eprinomectin in sheep faeces after a single topical administration of 0.5 mg kg(-1) b.w. of the drug. Because of its good recovery, precision, and sensitivity, the method has also proved applicable to further ecotoxicological studies of eprinomectin.
authors.affiliation: Institute of Physiology, Pharmacology and Toxicology, Veterinary Faculty, University of Ljubljana, Gerbiceva 60, 1000 Ljubljana, Slovenia. nevenka.kozuh@vf.uni-lj.si
authors.forename: Nevenka
authors.initials: N
authors.lastname: Kozuh Erzen
authors.forename: Lena
authors.initials: L
authors.lastname: Hodoscek
authors.forename: Vesna
authors.initials: V
authors.lastname: Cerkvenik-Flajs
mesh_terms: D000818:Animals; D005243:Feces / Q000737:chemistry; D007559:Ivermectin / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry; D015394:Molecular Structure; D012756:Sheep; D013696:Temperature; D013997:Time Factors
chemical_list: D007559:Ivermectin; C101434:eprinomectin