Trace enrichment of indole-3-acetic acid from leaf matrix

Abstract Eight different sorbents were evaluated for their adsorptivity and desorptivity of indole-3-acetic acid (IAA), a plant hormone. Among the sorbents studied, Thermosorb was found to be most efficient in enriching the unionized IAA from dilute aqueous acidic solution. Interfering components in plant leaf matrix could be washed off with water-immiscible organic solvents from a Chromosorb P column, while the ionized carboxylic acids were retained in the adsorbed water on the surface of Chromosorb P. The method of simple and efficient purification-enrichment of IAA using Thermosorb in conjunction with Chromosorb P, followed by the quantitative analysis employing C 18 reversed-phase high-performance liquid chromatography-fluorescence detector, has been applied to the determination of IAA in soybean plant leaves.