title: Determination of tilmicosin residues in cow and sheep milk by liquid chromatography.
abstract: This method was developed and validated to detect and quantitate tilmicosin residues in cow milk over a range of 0.010-10 microg/mL, and in sheep milk over a range of 0.025-0.5 microg/mL. The procedure involves extracting the milk sample with acetonitrile and using a C18 cartridge to perform a solid-phase extraction cleanup of the extract. A reversed-phase gradient liquid chromatography method with detection at 280 nm is used to separate the tilmicosin from matrix components in a 30 min run time. The limit of quantitation of the method is 0.010 microg/mL for cow milk, and 0.025 microg/mL for sheep milk. Average percentage recoveries for milk samples ranged from 82 to 94%. Percentage relative standard deviation values ranged from 3.1 to 17.2%.
authors.affiliation: Elanco Animal Health, a Division of Eli Lilly and Co, Greenfield, IN 46140, USA.
authors.forename: C M
authors.initials: CM
authors.lastname: Stobba-Wiley
authors.forename: R S
authors.initials: RS
authors.lastname: Readnour
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D002417:Cattle; D002853:Chromatography, Liquid / Q000379:methods* / Q000592:standards; D018942:Macrolides; D008892:Milk / Q000737:chemistry*; D008956:Models, Chemical; D011786:Quality Control; D012680:Sensitivity and Specificity; D012756:Sheep; D013048:Specimen Handling; D015645:Tylosin / Q000031:analogs & derivatives* / Q000032:analysis
chemical_list: D000900:Anti-Bacterial Agents; D018942:Macrolides; C052319:tilmicosin; D015645:Tylosin