Development and validation of a micellar liquid chromatography-based method to quantify melamine in swine kidney

Melamine is a toxic compound illegally added to animal feed to falsely boost protein content. This represents a strong threat to consumer's health, as melamine can reach human through the food chain. An easy and reliable micellar liquid chromatography-method was developed to detect melamine in swine kidney. The analyte was extracted by shaking in methanol. Melamine was eluted from the HPLC column without interferences in <8.0 min. Mobile phase was a 0.11 M sodium dodecyl sulfate - 7.5% propanol at pH 3 solution running under isocratic mode through a C18 column at 1 mL/min and absorbance detection at 210 nm. The method was validated according to the Food and Drug Administration guidelines: sensitivity, calibration range (0.3-30 μg/g), linearity (r2 > 0.9997), precision (<7.6%), accuracy (−8.3-3.6%), recovery (82.1-92.4%) and robustness (<5.1%). The methodology was applied to swine kidney samples purchased from a local supermarket. The method can be used as a screening method for routine post-mortem diagnose melamine intoxication in animals and detect feeding with poultry containing melamine, in order to withdraw the corresponding flesh. This would be mandatory to prevent consumer intoxication and improve the quality of food.