Analysis of methylated melamines in reaction mixtures by CZE-MS

A fast and reliable method based on CZE coupled to Q-TOF MS for the analysis of methylated melamines is presented. Experiments with UV detection were performed using BGE containing formic acid and TFA to optimize electrophoretic conditions and to achieve baseline separation. Employing a TFA-based electrolyte containing 80% ACN and MS detection, nine different methyl melamines were determined in real samples, which were produced by catalytic hydrogenation of melamine/formaldehyde reaction mixtures. The use of a Q-TOF MS resulted in LOD better than 0.01 mg/L for all compounds and high mass accuracy with mass errors lower than 2.3 ppm.