Single-Run Separation of Closely Related Cationic and Anionic Compounds by CE-ESI-MS: Application to the Simultaneous Analysis of Melamine and its Analogs in Milk
Isabelle Kohler,
Emmanuelle Cognard,
Ivano Marchi,
Didier Ortelli,
Patrick Edder,
Jean-Luc Veuthey,
Serge Rudaz,
Julie Schappler
Affiliations
Isabelle Kohler
School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Bd d'Yvoy 20, CH-1211, Geneva 4, Swiss Centre for Applied Human Toxicology, University of Geneva, CMU, Rue Michel-Servet 1, CH-1211 Geneva 4
Emmanuelle Cognard
Swiss Centre for Applied Human Toxicology, University of Geneva, CMU, Rue Michel-Servet 1, CH-1211 Geneva 4, Food Authority Control of Geneva, Quai Ernest-Ansermet 22, CP 76, CH-1211 Geneva 4
Ivano Marchi
Swiss Centre for Applied Human Toxicology, University of Geneva, CMU, Rue Michel-Servet 1, CH-1211 Geneva 4, Food Authority Control of Geneva, Quai Ernest-Ansermet 22, CP 76, CH-1211 Geneva 4
Didier Ortelli
Swiss Centre for Applied Human Toxicology, University of Geneva, CMU, Rue Michel-Servet 1, CH-1211 Geneva 4, Food Authority Control of Geneva, Quai Ernest-Ansermet 22, CP 76, CH-1211 Geneva 4
Patrick Edder
Swiss Centre for Applied Human Toxicology, University of Geneva, CMU, Rue Michel-Servet 1, CH-1211 Geneva 4, Food Authority Control of Geneva, Quai Ernest-Ansermet 22, CP 76, CH-1211 Geneva 4
Jean-Luc Veuthey
School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Bd d'Yvoy 20, CH-1211, Geneva 4, Swiss Centre for Applied Human Toxicology, University of Geneva, CMU, Rue Michel-Servet 1, CH-1211 Geneva 4
Serge Rudaz
School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Bd d'Yvoy 20, CH-1211, Geneva 4, Swiss Centre for Applied Human Toxicology, University of Geneva, CMU, Rue Michel-Servet 1, CH-1211 Geneva 4
Julie Schappler
School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Bd d'Yvoy 20, CH-1211, Geneva 4, Swiss Centre for Applied Human Toxicology, University of Geneva, CMU, Rue Michel-Servet 1, CH-1211 Geneva 4;, Email: [email protected]
In recent years, two adulteration incidents concerning the addition of melamine, a nitrogen-rich-industrial small polar compound, to pet food and infant formula products have occurred in China. These issues prompted laboratories to develop methods for the analysis of melamine and related compounds in a wide variety of food products and ingredients. In this context, a CE-ESI-MS method was developed to simultaneously analyze melamine and its related products (ammeline, ammelide and cyanuric acid) that possess close physico-chemical properties. This method allows the simultaneous analysis of both cations and anions in a single run, using CE to divide the run into two time segments in normal polarity mode. For this purpose, ESI polarity was switched once during the run, increasing sensitivity and data quality. The method was applied to spiked powdered milk and melamine-contaminated powdered milk, with two sample preparation procedures.
