This deuterated ganglioside is ideal for the identification of gangliosides in samples and biological systems using mass spectrometry.1 Gangliosides2 are acidic glycosphingolipids that form lipid rafts in the outer leaflet of the cell plasma membrane, especially in neuronal cells in the central nervous system.3 They participate in cellular proliferation, differentiation, adhesion, signal transduction, cell-to-cell interactions, tumorigenesis, and metastasis.4 The accumulation of gangliosides has been linked to several diseases including Tay-Sachs and Sandhoff disease. GM3 is the main ganglioside of human fibroblasts and can regulate fibroblast and epidermal growth factors5 and is also able to regulate the adhesion and migration of several carcinoma cell lines. GM3 was also shown to inhibit tumor cell invasion. GM3 can induce human promyelocytic leukemia HL-60 cells to differentiate to monocyte/macrophage lineage instead of granulocytes.6