QUANTIFICATION METHOD FOR ORGANIC COMPOUND INCLUDING SULFUR

摘要

The present invention relates to a method to quantify an organic compound containing sulfur. A compound containing sulfur can be quantified by a means of the method of the present invention without restriction, but the method is preferably more effective in quantifying an organic compound that is difficult to be quantified like a giant molecule (biomaterial) or an absorptive/hydrate material. The method of the present invention can very effectively quantify a high purity standard material of peptides or proteins from among the biomaterial. An internal standard solution, whereby any one isotope selected from (^33)S, (^34)S, and (^36)S is concentrated, is used in order to measure the isotope ratio of sulfur that is contained in methionine or cysteine among the amino acid of peptides or proteins. As a control material, a sulfur element standard solution is used as a correcting standard solution. A sample is acid-decomposed so that sulfur is decomposed into an inorganic material form. Then, the isotope ratio of any one isotope selected from (^33)S, (^34)S, and (^36)S-(^32)S is measured. By the means of the method by which the concentration of a sample is calculated, the investigation and quantification of the impurities including sulfur are performed together, so that a certification value (quantification value) which satisfies SI traceability can be obtained.