Development and Validation of a Method forDetermination of Tilmicosin Residues in EquinePlasma and Tissues Using HPLC

摘要

A sensitive liquid chromatographic method with UV detection has been developed for the analysis of tilmicosin concentrations in equine tissues and plasma. Tilmicosin is extracted from plasma or tissues using acetonitrile and a phosphate buffer. The extract is centrifuged, filtered, and cleaned up on a conditioned C_(18) solid phase extraction cartridge. Tilmicosin is eluted with ammonium acetate in methanol and diluted with ammonium acetate. It is analyzed by reversed phase liquid chromatography with UV detection at 287 nm. The method was shown to be suitable for detecting tilmicosin in equine plasma, muscle, liver, kidney, and lung tissues. The limit of detection of the method was 13ng/mL in plasma and 181 ng/g in lung tissue.