Liquid chromatography–high-resolution electrostatic ion-trap mass spectrometric analysis of GD3 ganglioside in dairy products

Gangliosides are thought to play a role in modifying the intestinal microflora and promoting neural development in the neonate. Milk is a good source of gangliosides, which are localised in the milkfat globule membrane. Robust quantitative analysis is required to underpin any claims made on ganglioside content in milk products. We have modified and validated our previously published method to quantify the amounts of the two predominant gangliosides classes, GD3 and GM3, in a range of bovine dairy products. After extraction and separation using hydrophilic high-performance liquid chromatography, an LTQ-Orbitrap™ mass spectrometer was used to extract and sum the major species of GD3 and GM3, generating fully resolved extracted ion current peaks for both standards and samples. The method had good repeatability (coefficient of variation 2–8%) and its results compared favourably with thin layer chromatography, a method that has been used extensively in the literature for the quantification of gangliosides in various sample matrices.