HPLC determination of sulphonamide residues in field samples of buffalo meat

A selective and sensitive reverse phase liquid chromatographic method with UV detection has been used for simultaneous determination of selected sulphonamide residues in buffalo meat samples. Samples were extracted by liquid-liquid extraction using acetonitrile, n-hexane solution and the analysis was carried out using a reverse phase HPLC using UV detector. The chromatographic separation was achieved in a C₁₈ column using mobile phase consisting of glacial acetic acid in acetonitrile, methanol and water (85:10:5, v/v) with an isocratic elution mode. The volume of injection and flow rate of the mobile phase were 40 jl and 1.5 ml/min respectively. UV detector was operated at a wavelength 254 nm.Linearity range10-500|jg/Kg.Extraction recoveries of sulphonamides were in the range83-88%.The LOD for sulphonamides viz. sulfadiazine,sulfadoxine, sulfamethazine, sulfamethoxazolewas6.06, 7.63, 6.79and 10.68 jg/Kg and the LOQ were 18.37, 23.12, 20.57and 32.37 jg/Kg, respectively.A total of 100 samples of buffalo meat analysed for the presence of sulphonamide residues showed one sample positive for sulfamethazine residue and its level was below codex MRL (100 jg/Kg).