Preparation of radiolabeled GM2 and GA2 gangliosides.

GM2 and GA2 gangliosides from the brain of a patient who died of Sandhoff's disease were purified by solvent partition, silicic acid and silica gel column chromatography, and silica gel preparative thin-layer chromatography. They were tritiated in the terminal N-acetylgalactosamine residue using galactose oxidase and sodium [3H]borohydride with the inclusion of catalase and peroxidase into the oxidation reaction. The specific activities were 4.62 X 10(8) dpm/mumol of GM2 ganglioside and 5.54 X 40(7) dpm/mumol of GA2 ganglioside. The addition of catalase and peroxidase to the tritiation procedure is recommended.