Melamine (2,4,6-triamino-s-triazine) is a colourless substance and chemically a heterocyclic aromatic compound that contains nitrogen oxide. The term melamine is also commonly used for a plastic material from the group of duroplasts / aminoplasts.

In 2008 Chinese dairy factories and baby food manufacturers extended milk powder and other milk products with melamine. The raised nitrogen oxide content simulates a higher concentration of protein, since in food analytics the nitrogen oxide content is used to determine the protein content based on the Kjeldahl method. The toxic effect of melamine on the kidneys caused the death of six infants and around 294,000 cases of kidney stones in children in China. Melamine was also found in milk convenience foods and in ordinary milk.

ifp tests for melamine using HPLC coupled with double mass spectrometry (LC-MS/MS) after extraction from the sample materials.  

Other prohibited sources of nitrogen oxide are detected at the same time: dicyandiamid (DCD), cyanuric acid, uric acid, biuret, cyromazine and amidine urea.