New polymeric sorbent for the solid-phase extraction of indole-3-acetic acid from plants followed by liquid chromatography — Fluorescence detector

Plant hormones play a crucial role in controlling plant growth and development. These groups of naturally occurring substances trigger physiological processes at very low concentrations, which require sensitive techniques for their quantitation. This study reports on the development of a newly synthesized polymer sorbent for the analysis of indole-3-acetic acid (IAA), which is the most important auxin in plants, from complex raw matrices, such as plant extracts. IAA was determined by high-performance liquid chromatography (HPLC) coupled with fluorescence detection (FD). The polymer developed was able to bind about 94% of IAA with a reproducible manner. This methodology was developed and applied for the determination of IAA in lemon leaves infected and uninfected with Pseudomonas syringae, demonstrating that IAA concentrations are higher in infected than in uninfected samples.