Determination of cephalexin residual level using ultra-high-performance liquid chromatography-tandem mass spectrometry: Residue depletion study in swine

Abstract An ultra-high-performance liquid chromatography-tandem mass spectrometry method was developed to analyze cephalexin in swine tissues, urine, and feces. Samples were extracted with 1% sulfuric acid, followed by purification using MCX cartridges. Mean recoveries were 95.4%–100.7% with inter-day relative standard deviations of