High-performance liquid chromatography determination of phenolic components in wine using off-line isotachophoretic pretreatment

The off-line combination of isotachophoresis (ITP) and high-performance liquid chromatography (HPLC) to improve sample pretreatment and determination of phenolic compounds in wine was investigated. The ITP system provided an enhanced sample load capacity and served as a sample clean-up technique, HPLC performed a final separation of the analytes presented in samples. The phenolic components were separated by Discovery RP Amid C16 chromatography column using water-methanol-acetonitrile-orthophosphoric acid gradient. The identification of phenolic compounds was made by comparison of the retention data obtained for the standard mixture, pretreated sample and the sample spiked standard additions. Satisfactory recoveries for all components analysed were observed between 86.1 and 109.2%.