METHOD OF PEPTIDE SEQUENCING BY MASS-SPECTROMETRY AND DEFINING OF THEIR AMINO ACID SEQUENCES Russian patent published in 2013 - IPC H01J49/00 G01N33/68 

FIELD: electricity.

SUBSTANCE: method of peptide sequencing by mass-spectrometry and defining of their amino acid sequences is based on fragmentation in mass-spectrometer ion source between the nozzle and skimmer for molecular ions of peptides under the action of controlled electric field and subsequent mass-spectrographic analysis of fragments. Peptide comes to the ion source which electrogasdynamic system allows control of fragmentation degree for molecular ion by means of electric field changing. Further ions are divided in mass analyser and delivered to detector where mass spectrum of the peptide and its fragments with different fragmentation depth in the same spectrum is registered. Mass spectra of the peptide fragments obtained at different values of the electric field force are processes by the recording system, analysed and amino acid sequence is defined for the source peptide in result. Controlled degree of fragmentation in the ion source under action of the varied electrical field within the range of 10²-10⁴ V/m and residual gas pressure within the range of 100-2000Pa allows determination of amino acid sequence of peptides containing up to 10-15 amino acid residues which corresponds to an average length of peptides, products of protein enzymatic hydrolysis.

EFFECT: simplification and speeding up of the system.