A NEW PROCEDURE FOR QUANTITATIVE ANALYSIS BY ISOTOPE DILUTION, WITH APPLICATION TO THE DETERMINATION OF AMINO ACIDS AND FATTY ACIDS

Abstract

We shall describe here a quantitative method of analysis of organic compounds in mixtures. The procedure requires the isolation of only a small sample of the substance to be determined, the yield being unimportant. This method is based on the fact that a compound which has an abnormal isotope content is inseparable by the usual laboratory procedures from its normal analogue. If, for example, a deuteropalmitic acid is added to a mixture of isotopically normal fatty acids, and then palmitic acid is isolated, this will be a representative sample of the mixture of the added deuteropalmitic acid and the palmitic acid originally present. From the amount of palmitic acid added (2) and its deuterium content (Co),1 as well as the deuterium content of the isolated palmitic acid (C), the amount (y) of palmitic acid originally present in the mixture can be calculated from Equation 1.