High-performance liquid chromatographic isolation of uric acid from soil for isotopic determination

Abstract

Uric acid was extracted from soil into potassium phosphate solution and isolated from other components by high-performance liquid chromatography, then the isolated fraction was subjected to nitrogen isotope analysis. Studies of the adsorption of uric acid on clay indicated no significant isotope fractionation during the exchange reaction; hence the isotope ratio found in the extract was the same as that in the soil. An increase in soil ammonia content followed the decomposition of uric acid. No uric acid isotopic preference by uric acid bacteria during the decomposition was found. The fractionation at the time of ammonia evaporation was mainly responsible for the high nitrogen isotope ratio in bird rookeries. An extremely high ratio for soil ammonia was found in a simulation experiment. This phenomenon may be mimicked in nature.