Liquid chromatographic method for the analysis of tocopherols in malt sprouts with supercritical fluid extraction

A simple, specific and sensitive high-performance liquid chromatographic method has been developed for the determination of tocopherols in malt sprouts. A supercritical fluid extraction (SFE) procedure was used to isolate tocopherols from the vegetal matrix before quantitative analysis. The analytes were separated on a Zorbax reversed-phase column using methanol–water as mobile phase and quantified by measuring its fluorescence at λem=328 nm after excitation of the analytes at λexc=303 nm. The limits of detection for α-, γ- and δ-tocopherols were 0.04, 0.05, and 0.05 μg/ml, respectively. The calibration graphs of the method were linear from 0.1 to 1.5, 0.2 to 2.5, and 0.2 to 2.0 μg/ml, for α-, γ- and δ-tocopherols, respectively. This SFE and HPLC procedure is simple, precise and accurate for the determination of tocopherols in malt sprouts.