Determination of sulfamethazine in milk by solid phase extraction and liquid chromatographic separation with ultraviolet detection

A simple, rapid and inexpensive method has been developed for the determination of sulfamethazine (SMZ) in milk without interferences from other sulfa drugs. The method involves solid-phase extraction, liquid chromatographic separation and ultraviolet detection. Method precision (RSD < 4%) and absolute recovery (>80%) were satisfactory. The quantification limit, 10 μg/kg, indicated that the current maximum permissible concentration of SMZ in milk (100 μg/kg) can be monitored by this method