Determination of Kanamycin A in Animal Feeds by Solid Phase Extraction and High Performance Liquid Chromatography with Pre‐Column Derivatization and Fluorescence Detection

Abstract A selective method was developed for the determination of kanamycin A in medicated animal feeds by reversed‐phase high performance liquid chromatography (HPLC) with precolumn derivatization. Samples were extracted with 0.1 mol/L hydrochloric acid solution and cleanup was achieved with MCX solid phase extraction (SPE). The purified extract was derivatized with O‐phthaladehyde (OPA), separated on a reversed‐phase C18 column and the fluorescence detection was performed at the excitation and emission wavelengths of 230 and 389 nm, respectively. The run time was approximately 14 min, at the flow rate of 0.8 mL/min. This method provides the average recoveries 98.4%–106.0% in feeds spiked in the range of 10–2000 g/ton, with the coefficients of variation 1.17%–9.78%. The limit of detection in feeds was 5 g/ton and the limit of quantification in feeds was 10 g/ton, which are well below the effective dose.