title: Determination of tylosin in feeds by liquid chromatography with solid-phase extraction.
abstract: A method was developed for the determination of tylosin in feeds. The method involves extraction of tylosin with methanol, concentration under a stream of nitrogen, and cleanup using Phenomenex C18 solid-phase extraction cartridge. Analyte separation and quantitation were achieved by gradient reversed-phase liquid chromatography and UV absorbance at 285 nm with a reference wavelength of 320 nm with column temperature of 45 degrees C. Average spike recoveries for samples prepared at 4 spiking levels (22.7, 181, 907, and 1000 g/ton) were 111.0, 94.9, 96.2, and 98.6%, respectively. The overall method precision at each of the 4 spiking levels was < or = 7.85% relative standard deviation. The limits of detection and quantitation (g/ton) were 2.16 and 7.20 g/ton, respectively.
authors.affiliation: State of Wisconsin, Department of Agriculture, Trade and Consumer Protection, Bureau of Laboratory Services, 4702 University Ave, PO Box 7883, Madison, WI 53707-7883, USA. matthew.gramse@datcp.state.wi.us
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Gramse
authors.forename: Paul E
authors.initials: PE
authors.lastname: Jacobson
authors.forename: James C
authors.initials: JC
authors.lastname: Selkirk
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D002853:Chromatography, Liquid; D015645:Tylosin / Q000032:analysis* / Q000302:isolation & purification
chemical_list: D015645:Tylosin