[Analysis of the NeuAc-LacCer ganglioside structure and its analogs by mass spectrometry with bombardment with accelerated atoms].

Gangliosides NeuAc-LacCer, NeuGc-LacCer, NeuLac-Sph and NeuAc-LacSphAc were analysed by FAB mass spectrometry in the negative ion mode. It is shown that this method gives valuable information on the structure of carbohydrate chains and fatty acid residues of the ganglioside molecules taking only micrograms of substances.

[Modification of a method of determining 15N in biological material].

A method is described for preparation of nitrogen samples and estimation of 15N concentration in free amino acids and urea, isolated from heart muscle, using mass-spectometric analysis. Components of the tissue extracts were separated at the preparative scale; amino acids and urea were desalted by means of ion exchange chromatography. CHN-analyzer was used to measure content of nitrogen in urea and amino acids.