| 摘要 |
PURPOSE:To greatly improve the linearity of the calibration curve in a low concn. region concerning a component of early elution after ytterbium by allowing an arom. or cyclic amine having a specific pKa range such as pyridine to co-exist at the time of a color forming reaction. CONSTITUTION:A sample contg. a rare earth element is subjected to cation exchange chromatography which executes elution by using an alpha- hydroxycarboxylic acid soln. 2, 7-bis(2-arsono-phenylazo)-1,8-dihydroxynaphtha lene-3,6-disulfon ic acid and the arm. amine or cycline amines of 3-7pKa are added to the eluate thereof to effect the color forming reaction. The rare earth element in the sample is separated and determined in accordance with the intensity of the color formation. An aq. soln. of the alpha-hydroxycarboxylic acid is adequate as the moving phase to be used for this cation exchange chromatography. The use of the aq. soln. prepd. to weak acidity of 2-5pH by addition of an alkali thereto is suitable in terms of an increase in generation sensitivity. |
