Determination of five sulfonamides in medicated feedingstuffs by liquid chromatography with ultraviolet detection

A fast and reliable method of liquid chromatography and ultraviolet detection of sulfaguanidine, sulfadiazine, sulfamethazine, sulfamethizole, and sulfamethoxazole in feedingstuffs was described. The method involves THE procedure of preparation of spiked samples, and extraction of sulphonamides from the matrix using a mixture of methanol and acetonitrile, followed by drying the extract and dissolving it in a phosphate buffer. The analysis uses octadecyl (C18) analytical column with UV detection at λ = 260 nm and a gradient programme of mobile phase composition. The analytical procedure has been successfully adopted and validated for quantitative determination of the sulfonamides in feedingstuff samples. Validation included sensitivity, specificity, linearity, repeatability, and intra-laboratory reproducibility. The mean recovery of sulfonamides was 84%, within the working range of 200-2000 mg/kg. Direct, simple sample preparation and HPLC-UV analysis allow the method to be successfully included in the scope of routine analyses. The presented results could be an answer to a need of simple and easy method for sulfonamide determination applicable in medicated feedingstuffs analysis.