In this study, we investigated the application of different
solid–liquid extraction methods followed by SPE, and matrix solid-
phase dispersion for the isolation of selected phenolic acids, and
flavonoids from E. arvense L. herb. The most effective technique for
isolation of analyzed compounds was ultrasound assisted extrac-
tion at 60 ◦ C in three cycles for 30 min, with 80% aqueous solution
of methanol. Other extraction methods used in experiment gives
definitely less yield of polyphenols. Satisfactory yields for these
compounds cannot be obtained also by the use of MSPD.
USAE proved to be an effective, and precise technique. This tech-
nique (followed by SPE) exhibited appropriate extraction efficiency,
reproducibility, and recovery. All of these results clearly infer, that
USAE could be useful to extract phenolic compounds from plant
material.