High-performance liquid chromatographic determination/identification of oxytetracycline and sulphadimidine in meat and eggs

Summary A rapid method for the simultaneous determination/identification of residual oxytetracycline (OTC) and sulphadimidine (SDD) in meats (beef, pork, chicken) and eggs by high-performance liquid chromatography (HPLC) was developed. The extraction of OTC and SDD was performed using a Sep-Pak^? CN cartridge. The extracts contained OTC/SDD analytes when examined by HPLC using a LiChrospher^? 100 RP-8 end-capped column and a mobile phase of acetonitrile-acetic acid-water (28:4:68, v/v/v) with a photodiode array detector. The average recoveries from spiked samples (0.1 μg g⁻¹ and 1.0 μg g⁻¹) were in excess of 80.2% with coefficients of variation between 1.5 and 5.0%. The limits of detection for OTC and SDD were 0.05 and 0.02 μg g⁻¹, respectively.