Analytical methods of stable isotope concentration

摘要

PROBLEM TO BE SOLVED: To provide a concentration analyzing method of a stable isotope effective for determining the concentration of the isotope of a hardly volatile substance such as an amino acid or the like labelled in a low concentration of below 50 atom% in isotope labelling ratio.;SOLUTION: When the concentration of the isotope of a low concentration labelled sample is analyzed, a matrix solution wherein an acid aqueous solution and an alkali metal ion-containing aqueous solution are added is used as a matrix solution of an FAB method and this matrix solution is mixed with a sample to perform mass analysis. The concentration of the stable isotope is calculated from the intensity ratio of the first peak of an alkali ion added molecule ions, wherein an alkali metal is added to a molecule highest in presence probability, and a second peak, which is the peak of an alkali metal ion added molecule ions next high in presence probability and appears on the high mass number side by one mass number of the first peak, in the obtained mass spectrum.;COPYRIGHT: (C)2008,JPO&INPIT