Solid phase extraction/cyclodextrin-modified micellar electrokinetic chromatography for the analysis of melatonin and related indole compounds in plants

FEDERICO JOSE VICENTE GOMEZ; ISMAEL GATICA-HERNáNDEZ; SOLEDAD CERUTTI; M. FERNANDA SILVA

MICROCHEMICAL JOURNAL

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2015 vol. 123 p. 22 - 27

0026-265X

The identification of melatonin in plants has inspired new investigations to understand its biological function. Inthis work, a robust, reliable, low-cost, quick and simple method based on solid phase extraction followed bymicellar electrokinetic chromatography for the extraction, preconcentration and simultaneous determinationof melatonin, tryptophan, serotonin and indole-3-acetic acid in plant material is proposed. Extraction of indolecompounds from plant tissues was enhanced by ultrasound and solid phase extraction, which was carried outwith C8 SPE cartridges. The use of a dual pseudostationary phase system, involving a mixture of SDS anionicmicelles and â-cyclodextrin, enabled to reach adequate selectivity. A BGE of 10 mM sodium tetraborate(pH 9.2), containing 20 mM â-CD, 20 mM SDS, and 10% (v/v) of acetonitrile, allowed baseline separation inless than 10 min. The proposed methodology provided limits of detection (LODs) down to low ppb levels.Under the optimal conditions, a successful application on Arabidopsis tissue, green, and linden tea leavesconfirmed the validity of this method for food analysis and as a tool to contribute to the elucidation of thebiological role of melatonin in plants.