Characterization of the disposition of melamine in female Sprague-Dawley rats using ultra-performance liquid chromatography-tandem mass spectrometry.

This study characterized the concentration-time profile of melamine in the heart, liver, spleen, lungs, kidneys, bladder, feces, urine, and plasma after melamine (MM) administration. Female Sprague-Dawley rats received a single oral dose of 1.0 g/kg body weight. Samples (n=4 per time point) were collected at 12, 24, 48, 72, 96, 120, 144, and 168 h. Based on calculations of the area under the concentration-time curves after dosing, ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS) was used to detect MM concentration in tissues. Peak concentrations of MM are reached in the livers and lungs at 12 h after dosing and in hearts, spleens, kidneys, bladders, feces, urine, and plasma at 24 h after dosing. More than 90% of the ingested MM is excreted in feces and urine within 24 h. These results provided initial understanding of the tissue disposition of MM. Moreover, this study demonstrates that UPLC-MS-MS can be used to detect MM in biological samples.