Quantitation of absolute 2H enrichment of plasma glucose by 2H NMR analysis of its monoacetone derivative

A simple (2)H NMR method for quantifying absolute (2)H-enrichments in all seven aliphatic positions of glucose following its derivatization to monoacetone glucose is presented. The method is based on the addition of a small quantity of (2)H-enriched formate to the NMR sample. When the method was applied to [2-(2)H]monoacetone glucose samples prepared from [2-(2)H]glucose standards of known enrichments in the range of 0.2-2.5%, enrichment estimates derived by the NMR method were in good agreement with the real enrichment values of the [2-(2)H]glucose precursors. The measurement was also applied to monoacetone glucose derived from human plasma glucose samples following administration of (2)H(2)O and attainment of isotopic steady state, where glucose H2 and body water enrichment are equivalent. In these studies, the absolute H2 enrichment of plasma glucose estimated by the formate method was in good agreement with the (2)H-enrichment of body water measured by an independent method.