Determination of Plant Hormone Indole-3-Acetic Acid in Aqueous Solution

An electroanalytical method was developed for the determination of the phytohormone indole-3-acetic acid in water using a glassy-carbon electrode. The differential pulse voltammetry was combined with a purification step which involved the extraction of plant tissue and the separation of plant pigments by passing through column Oasis MCX. Indole-3-acetic acid can be determined under optimum conditions with a limit of quantification (LOQ) 2.7x10-6 mol L-1. The linearity range was from 1.8x10-6 to 6.6x10-4 mol L-1. The electroanalytical determination of indole-3-acetic acid is selective, fast and economic. The presence of other phytohormones as abscisic acid and cytokinins as isopentenyladenine, isopentenyladenosine, trans-zeatin, zeatin riboside does not interfere the determination of indole-3-acetic acid in plant sample.