Hollow fiber-liquid phase microextraction method based on a new deep eutectic solvent for extraction and derivatization of some phenolic compounds in beverage samples packed in plastics.

The present study describes a sensitive, efficient, and easy approach for isolation, enrichment, and derivatization some phenolic compounds in the beverage samples packed in plastic bottles. The sample preparation method is based on a hollow fiber-liquid phase microextraction technique using a deep eutectic solvent. The enriched analytes are determined by gas chromatography-mass spectrometry. For this purpose, a new deep eutectic solvent composed of 8-hydroxyquinoline and pivalic acid is synthesized and used as an extraction solvent. The solvent is mixed with chloroacetyl chloride as a derivatization agent and filled into a hollow fiber segment containing an iron wire within the lumen. The prepared stir bar (hollow fiber) is stirred into the sample solution in which sodium chloride is dissolved to increase ionic strength of the solution. Temperature of the solution is adjusted at 50 °C to improve efficiency of the extraction/derivatization procedure. Under optimum conditions, the introduced method indicated high enhancement (1652-3265) and enrichment (1085-1256) factors, low limits of detection (9-22 ng L-1) and quantification (29-76 ng L-1), good linearity (r2 ≥ 0.9950), and satisfactory repeatabilities. Finally, the proposed method was applied in analysis of the analytes in the various beverage samples packed in plastic packages.