HPLC Method for the Simultaneous Separation of Melamine and Cyanuric Acid on Zodiac HST TH Column

Melamine is an organic, basic compound derived from cyanamide and contains 66% nitrogen by mass. It has been used to artificially increase the apparent protein content in milk products. Cyanuric acid, a trimer of cyanic acid, is a slightly acidic and hydrophilic compound. Together, melamine and cyanuric acid can form an insoluble complex, and both have been implicated in adulteration practices aimed at manipulating nitrogen measurements. Zodiac HST TH, a reversed-phase ion-exchange column, was used to effectively separate melamine and cyanuric acid using an LC/MS-compatible mobile phase. This method offers a general approach for analyzing mixtures of basic and acidic hydrophilic compounds under LC/MS-friendly conditions.