Chemiluminescence determination of indole derivatives in human body fluids and soil by flow injection analysis using potassium permanganate

Abstract

A simple, sensitive and rapid flow-injection chemiluminescence (CL) method has been developed for the determination of indole derivatives including indole-2,3-dione (isatin) and indole-3-acetic acid (IAA), based on the increased CL reaction of potassium permanganate-formaldehyde system in acidic medium. Strong CL was observed when the indole derivatives were injected into the acidic potassium permanganate solution in a flow-cell. Under the optimum conditions, the linear range of the determination was 0.1–100.0 µM for isatin and 0.01–10.0 µM for IAA. The detection limit (3σ) was 10.0 nM for isatin and 1.0 nM for IAA. The method has been successfully applied to the determination of isatin in biological samples and of IAA in biological samples and soil extracts with satisfactory results.