Determination of low molecular weight organic acids in soil solution by HPLC

An HPLC method employing an ion exclusion column was developed for the dete rmination of low molecular weight organic acids in soil solution. The metho d includes extensive sample pretreatment using ultrafiltration and cation e xchange. The method showed linear calibration graphs (r > 0.99) and the lim its of detection in the range 0.1-26 mu M. The recovery of eleven added aci ds ranged from 89 to 102%. Soil solutions of five horizons of a podzolised soil were analysed. The results showed that these compounds made up 1-3% of the dissolved organic carbon and 0-14% of the acidity. Identification of t he major acids was also carried out by capillary zone electrophoresis. (C) 1999 Published by Elsevier Science B.V. All rights reserved.